Below is a glossary of terms found in our reviews.

To remove or otherwise destroy the biological function of any part (e.g. bone marrow).

Acceptable daily intake (ADI)
The amount of chemical that, if ingested daily over a lifetime, appears to be without adverse effect.

Acid steatocrit
An estimate of the amount of fat in stool (faeces)

Painful burning sensation in the hands and feet.

Acute chest syndrome
Respiratory syndrome characterized by the appearance of a new pulmonary infiltrate on chest x-ray, accompanied by symptoms of fever, cough, chest pain, tachypnea, or dyspnea, often seen in patients with sickle cell anemia; multiple factors (e.g. infection, and pulmonary fat embolism) may contribute to the development of the syndrome. 


Airway clearance techniques
Methods used to assist with secretion removal. There are several different techniques such as: chest physical therapy (CPT); positive expiratory pressure (PEP); high pressure PEP; flutter; autogenic drainage; and active cycle breathing.

An agent which acts relatively selectively on beta-2 adrenoceptors in the airways to cause bronchodilation. Its main clinical use is in asthma and is known in the UK as salbutamol, a brand name of this drug is Ventolin.

Alkylating agent
Agents used in cancer treatment that attaches an alkyl group (CnH2n+1) (hydrocarbon) to DNA (molecule of cell nucleus)

One of the variant forms of a gene at a particular locus, or location, on a chromosome. Different alleles produce variation in inherited characteristics such as hair color or blood type. In a dominantly inherited condition, if only one of the two genes is present, the disease/disorder occurs. In a recessively inherited condition, both genes must be present for disease to occur.

Allergic bronchopulmonary aspergillosis (ABPA)
An inflammatory and destructive disease of the bronchi and lungs due to the presence and growth of Aspergillus fumigatus.

Denoting or relating to cells or tissues from individuals belonging to the same species but genetically dissimilar (and hence immunologically incompatible)

Alpha globin
A blood protein found in the red blood cells. Alpha and beta globins combine to make haemoglobin, which carries oxygen.

The millions of tiny air sacs in the lungs, where oxygen and carbon dioxide are exchanged with the bloodstream.

An antibiotic used to treat deep-seated fungal infections.

Amino acids
The building blocks of proteins, there are 20 naturally occurring amino acids.

Broad spectrum antibiotics that are used to combat bacterial infections, can cause renal toxicity and hearing loss. Tobramycin and gentamicin are examples of these antibiotics and are often used by people with CF.

A condition where there are fewer red blood cells than average circulating in the blood stream. This may have a number of causes. See also 'Aplastic anaemia' and 'Sickle Cell Anaemia'.

A red, raised lesion.

Angiokeratoma corporis diffusum
An X-linked disorder caused by a deficiency of the lysosomal enzyme alpha-galactosidase A, also known as Anderson-Fabry disease.

Angiotensin receptor blocker
Medicines used to treat high blood pressure which work by keeping the body from using angiotensin (a hormone which raises blood pressure)

Loss of appetite.

Anterior fontanelle
The fontanelle occurring at the meeting point of the coronal and sagittal sutures (fibrous joints).

Science and practice of measuring the human body and its parts.

A drug which can destroy or inhibit growth of infectious organisms such as bacteria.

Antibiotic adjuvant
An agent that acts alongside an antibiotic, but itself has little or no bactericidal activity; it acts by increasing the organisms' susceptibility to the co-administered antibiotic.

A protein of the immune system, produced in response to an antigen (a foreign, often disease-causing, substance).

Anticholinergic agents
In airways these agents cause bronchodilation, an example of one of these agents is ipratroprium bromide.

Any protein or polypeptide substance (such as a toxin or enzyme) capable of stimulating an immune response

Destroying or inhibiting the growth of microorganisms

Antipseudomonal antibiotics
Antibiotic drugs tending to destroy bacteria of the genus Pseudomonas.

Antithrombin III
A coagulation inhibitory protein. 

Antithymocyte globulin
An infusion of horse or rabbit-derived antibodies against human T cells which is used in the prevention and treatment of acute rejection in organ transplantation.

Aplastic anemia
One type of anemia that occurs when the bone marrow produces too few of all three types of blood cells: red cells, white cells, and platelets. See also 'Anaemia'.

Aplastic Crisis
This occurs when the body stops making new red blood cells and is usually caused by an infection. This is a life-threatening condition and must be treated immediately with blood transfusion and treatment of any accompanying infection.

Apolipoprotein A1
The protein component of serum lipoproteins (HDL cholesterol). Small proteins containing multiple copies of the kringle domain.

Apolipoprotein B-100
The protein component of LDL cholesterol.

A condition in which the fingers are abnormally long and slender in comparison to the palm of the hand. 

Abnormal heart rhythm (either in time or force).

Pain about/from a joint, not associated with swelling or redness.

The inflammation of joints.

The accumulation of fluid in the peritoneal cavity.

Aseptic necrosis
See 'Avascular necrosis'.

Absence of symptoms. A person is asymptomatic if he/she has no symptoms.

A collapsed portion of the lung which does not contain air. This can be caused by excessive accumulations of mucous secretions, inhaled foreign bodies or bronchial cancers.

Atheromatous disease
A disease characterised by thickening and fatty degeneration of the inner coat of the arteries.

Refers to a group of inherited diseases where there is often and inherited tendency to develop allergic conditions.

Autogenic drainage
A combination of breathing control and breaths at various lung volumes.

Autosomal recessive
A genetic trait or disorder which appears only when an individual inherits a pair of chromosomes, each containing the gene for the trait. One chromosome of the pair comes from the father and the other from the mother. Autosomal recessive disorders can occur only if both parents are carriers of the trait. Cystic fibrosis and sickle cell disease are inherited in this manner.

Avascular necrosis
When blood vessels supplying bone get blocked, resulting in tiny breaks within the bone which can eventually cause the bone to collapse and bone death to occur. Also called aseptic necrosis and osteonecrosis.

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A single-celled organism. Bacteria are found throughout nature and can be beneficial or harmful.

A virus that infects bacteria.

See 'Bronchoalveolar lavage'.

Of mild type or character that does not threaten health or life.

Beta-2 agonists
Drugs which act on B2 receptors. These receptors are found in the airways and these drugs cause bronchodilation by relaxing the muscles in and around the airways that tighten during an asthma episode, e.g. albuterol.

Beta globin
A blood protein found in red blood cells that when mutated can lead to sickle cell disease. Beta and alpha globins combine to make haemoglobin, which carries oxygen.

Of, relating to, or conveying bile.

A pigment produced when the liver processes waste products. A high bilirubin level causes yellowing of the skin.

A thin layer of micro-organisms (e.g. bacteria) that form on and coat various surfaces. Various substances coat the biofilm and provide protection to those organisms living within the biofilm.

A group of drugs that prevent the loss of calcium from bone and its transfer to the bloodstream. They are used to strengthen the bones in the treatment of Paget's disease (in which the bones become deformed and fracture easily), to lower high concentrations of calcium in the blood in patients with bone cancer, and to treat or prevent osteoporosis.

Brasfield chest radiograph score
A system for scoring chest X-rays in cystic fibrosis.

Body mass index (BMI)
A measure of nutritional status, BMI = weight in kg/(height in metres)2

Bone marrow
The soft, spongy tissue found in the centre of most large bones that produces the cellular components of blood: white cells, red cells and platelets.

Bone matrix
The major constituent of bone.

Broad spectrum antibiotics
Antibiotics that are active against a wide variety of microorganisms.

Bronchial drainage
See 'Postural drainage'.

Bronchial lavage
A procedure in which small volumes of saline are rinsed through the lungs, followed by suction. It may be used in the treatment of CF to aspirate mucus secretions.

Persistent and progressive dilation of bronchi (branches from the trachea which lead to the lungs) often as a consequence of inflammatory disease (lung infections).

to do with the fine, thin-walled, tubular extensions of a bronchus

Bronchoalveolar lavage
Saline is instilled by means of a bronchoscope which has been advanced as far as possible into the lungs and the fluid aspirated out from the alveoli.

A medication that acts to dilate (enlarge) the lumen of the airway to allow the unrestricted passage of air. Examples include: theophylline, aminophylline, adrenaline, Alupent, metaproterenol, isoproterenol, Ventolin, Proventil, bitolterol, salmeterol, pirbuterol and albuterol.

Spasmodic tightening or contracting of muscles surrounding and supporting bronchial tubes interfering with normal breathing and causing respiratory distress. Occurs in asthma attacks, in CF and other conditions.

See 'Gastrostomy'.

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The deposition of calcium and phosphate in tissues such as the kidney.

A chemical reaction in which a carboxylic acid group is introduced in a substrate.

Relating to the heart.

A weakening of the heart muscle (myocardium), which usually causes inadequate heart pumping. It can be caused by viral infections, heart attacks, alcoholism, long-term and severe hypertension (high blood pressure).

Cardiopulmonary failure
Heart and lung failure.

Carrier (as in genetics)
An individual who possesses one copy of a mutant allele that causes disease only when two copies are present (an autosomal recessive disease). Although carriers not affected by the disease, two carriers can produce a child who has the disease.

The metabolic breakdown of complex molecules into simpler ones, often resulting in a release of energy.

See 'Complete Blood Count'.

Cerebellar ataxia
The failure of muscular coordination and irregularity of muscular action characterized by defects in rate, range, force and direction of movement of limbs.

Of or relating to the brain and spinal cord or to these together with the cranial and spinal nerves that innervate voluntary muscles.

Pertaining to the blood vessels of the cerebrum or brain.

See 'Cystic Fibrosis'.

See 'Cystic Fibrosis Transmembrane Conductance Regulator'.

Chelation therapy
The removal of heavy metal poisoning using agents which separate the metal from organs or tissues and bind it firmly with a new compound which can be eliminated from the body.

Chest physiotherapy
A treatment in diseases such as Cystic Fibrosis. Used to mobilise secretions and promote the removal of these secretions by an effective cough.

Chimeric antibody
A hybrid substance combining antibodies and parts of antibodies with the potential to track down and illuminate remote and microscopic tumours. It is less easily rejected by the body's immune system than the ordinary monoclonal antibody. 

A soft, waxy substance that is present in all parts of the body including the nervous system, skin, muscle, liver, intestines, and heart. It is made by the body and obtained from animal products in the diet.

Tending to diminish or stop the flow of bile.

A structure found in the cell nucleus that contains the genes; chromosomes are composed of DNA and proteins. Each parent contributes one chromosome of each pair, so children get half of their chromosomes from their mothers and half from their fathers.

The collective term for a set of laboratory techniques for the separation of mixtures.

Chronic sepsis
The presence in the blood or other tissues of disease causing microorganisms.

Ciliary beat frequency
The rate at which the cilia beat (cilia are fine hair-like projections from certain kinds of cells; they line the respiratory tract and move in rhythmic unison to "sweep" away fluids and particles within the lungs).

Widespread disruption of normal liver structure by fibrosis and the formation of regenerative nodules that is caused by any of various chronic progressive conditions affecting the liver.

A broad-spectrum quinolone antibiotic that can be given orally and is particularly useful against Gram-negative bacteria, such as Pseudomonas, that are resistant to all other oral antibiotics.

See 'Chest Physiotherapy'.

A disorder of the blood clotting (coagulation) system in which bleeding is prolonged and excessive.

A non-protein chemical compound that is bound to a protein and is required for the protein's biological activity.

Collateral ventilation
The entrance of air into alveoli through pulmonary alveolar pores and other pathways so that a lobule may remain aerated even though its bronchiole is obstructed. Also known as collateral respiration.

An antibiotic effective against Pseudomonas administered in nebulised form or intravenously in the treatment of CF.

Complete blood count
A measurement of size, number, and maturity of the different blood cells in a specific volume of blood.

A group of blood tests involving 14 parameters that measure glucose level, protein level, electrolyte and fluid balance, kidney function and liver function

Any trait or condition that exists from birth.

Confidence interval
A measure of the uncertainty around the main finding of a statistical analysis.  Estimates of unknown quantities, such as the odds ratio comparing an experimental intervention with a control, are usually presented as a point estimate and a 95% confidence interval. This means that if someone were to keep repeating a study in other samples from the same population, 95% of the confidence intervals from those studies would contain the true value of the unknown quantity.  Alternatives to 95%, such as 90% and 99% confidence intervals, are sometimes used.  Wider intervals indicate lower precision; narrow intervals, greater precision.

Cor pulmonale
Enlargement of the right ventricle of the heart due to resistance of the passage of blood through the lungs. Can often lead to right heart failure. This can be a major complication of chronic pulmonary diseases such as CF.

Corpora cavernosa
A mass of erectile tissue with large interspaces capable of being distended with blood; especially one of those that form the bulk of the body of the penis or of the clitoris.

Corpus spongiosum
The median longitudinal column of erectile tissue of the penis that contains the urethra and is ventral to the two corpora cavernosa.

Correlation co-efficient
A correlation coefficient can range from -1 for perfect negative correlation, to +1 for perfect positive correlation (with perfect meaning that all the points lie on a straight line).  A correlation coefficient of 0 means that there is no linear relationship between the variables.

Relationship by blood or by a common ancestor. 

Also known as rales, a soft fine crackling sound heard in the lungs through the stethoscope. Made either by air passages and alveoli (air sacs) opening up during inspiration or by air bubbling through fluid. They are not usually heard in healthy lungs.

Cross-over trial
A type of clinical trial comparing two or more interventions, in which the participants, upon completion of the course of one treatment, are switched to another.

The precipitate that forms when plasma is frozen and then thawed, particularly rich in fibronectin and blood clotting Factor VIII.

Cyclic peptide
An unusual class of compounds that range from antibiotics, such as bacitracin and polymyxin B, to the immunosuppressant drug cyclosporin. They can also be toxins. They tend to survive the human digestive process and can bind proteins in the cell where traditional drugs cannot.An unusual class of compounds that range from antibiotics, such as bacitracin and polymyxin B, to the immunosuppressant drug cyclosporin. They can also be toxins. They tend to survive the human digestive process and can bind proteins in the cell where traditional drugs cannot. 

Cystic fibrosis
A genetic disease with symptoms that usually appear shortly after birth. They include breathing difficulties and respiratory infections due to accumulation of sticky mucous problems with digestion and excessive loss of salt in sweat. The disease affects many organs including the lungs, gastrointestinal tract, pancreas and liver.

Cystic fibrosis transmembrane conductance regulator
A protein, involved in the movement of salt across cell membranes, which is lacking or does not function normally in people with cystic fibrosis.

Protein molecules, released by cells when activated by antigen, that are involved in cell-to-cell communications, acting as enhancing mediators for immune responses through interaction with specific cell-surface receptors on leucocytes.

A reduction in the number of cells circulating in the blood.

Tending to retard cellular activity and multiplication.

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Painful swelling of the feet and hands during the first several years of life of children with sickle cell anaemia.

Describing a compound from which one or more acyl groups (an organic radical derived from an organic acid by the removal of the carboxylic hydroxyl group) has been removed.

A drug which acts by combining with the excess iron in the body to form a complex which is excreted in the urine. This over a period of time leads to reduction in the iron overload in the body. Also known as L1.

A large and complex molecule with a very well-defined chemical structure.

Dermatan sulphate
A glycosaminoglycan (15-40 kD) found mostly in skin, but also in blood vessels, heart valves, tendons, and lungs; it is broken down by L iduronidase, but accumulates intra lysosomally in Hurler syndrome and Hunter syndrome. 

Relating to  the skin.

A drug that combines with iron in body tissues and fluids and is used to treat iron overload (including that resulting from prolonged or constant blood transfusion, as for thalassaemia), diseases involving iron storage in parts of the body, and for the diagnosis of such diseases.

Diabetes (Diabetes mellitus)
A pancreatic disorder that causes abnormal insulin production. This affects the body's ability to utilise sugar and other food substances and is usually treated by diet modification (restricted sugar intake) and use of insulin. In cystic fibrosis, disruption of pancreatic function sometimes leads to a form of the disease called cystic fibrosis related diabetes mellitus (CFRDM).

Distal intestinal obstruction syndrome
Occurs in CF and a form of partial intestinal obstruction which presents with a history of cramping pain and changes in stool pattern in absence of other acute GI symptoms. Usually responds to medical treatment.

Deoxyribonucleic acid, the chemical coding for a gene. DNA determines the "genetic message" within each cell, organ, and organism.

A condition in which the limbs are unusually long. 

First part of the small intestine.

Dysostosis multiplex
Defective skeletal formation involving individual bones, singly or in combination, which manifests primarily in the hands, skull, thorax, pelvis and vertebrae; commonly present in lysosomal storage diseases. 

Shortness of breath, difficult or laboured breathing.

painful urination.

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Standard ultrasound techniques used to image two-dimensional slices of the heart to diagnose cardiovascular disease.

Efflux pump
A mechanism located in the cell wall allowing substances toxic to the cell to be removed.

Efflux pump inhibitor
A molecule that interferes with the process of removing toxic substances and antibiotics from the cell.

Planned as opposed to emergency treatment.

The transthoracic interpretation of the electrical activity of the heart captured and externally recorded by skin electrodes.

Any of the ions (as of sodium or calcium) that in biological fluid regulate or affect most metabolic processes.

The motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric field.

The blocking or obstruction of a blood vessel or organ by the lodgement of a material mass (as an embolus).

Enamel hypoplasia
Arrested development, normal size or an immature state of part of the teeth structure.

A disease of the brain; especially one involving alterations of brain structure.

Widely prevalent in a particular region.

Within the bronchi or bronchial walls.

The process by which materials enter a cell without passing through the cell membrane, the plasma membrane folds inward to bring substances into the cell.

Caused by factors inside the organism or system.

A medical procedure to see inside the body using a long tubular instrument with a camera at the end (called endoscope); depending on which part of the body is to be seen, there are different names for it such as laparoscopy, bronchoscopy, colonoscopy etc. - bronchoscopy is the procedure to look inside the airways (breathing tract).

The thin layer of cells that line the interior surface of blood vessels.

Enteral Nutrition
Nutrition provided through a tube or catheter that delivers the nutrients directly into the stomach.

A special coating applied to tablets or capsules which prevents release and absorption of their contents until they reach the intestines.

Substances which help produce and/or accelerate certain chemical processes in the body, such as breaking down of foods during digestion. Individuals with cystic fibrosis may need pancreatic enzyme replacements to help with proper digestion of food.

Of, or relating to, the anterior walls of the abdomen.

Epithelial tissue
Cells which form a lining on the outside of the body and on the inside of the respiratory and digestive tracts and other organs.

Any method of measuring the amount of work done by an organism, usually during exertion.

See 'Expiratory Reserve Volume'.

Abnormal redness of the skin or other surface due to capillary congestion (as in inflammation).

Automated red cell transfusion.

Red blood cells containing haemoglobin, the substance which carries oxygen in the bloodstream.

The process by which red blood cells (erythrocytes) are produced.

Essential thrombocythaemia
A condition characterised by the production of large numbers of abnormal platelets. Symptoms include haemorrhage, blood clots and enlargement of the spleen.

Aggravation of symptoms or increase in the severity of a disease.

To spit; to eject saliva, mucus, or other fluid from the mouth.

Expiratory reserve volume
This represents the reserve volume of air you can exhale after you have exhaled normally during a resting respiration. Again, your body can call upon this reserve to increase the amount of air exchange.

Exocrine glands
Glands which secrete substances through ducts to surrounding surfaces. Includes sweat, salivary and tear glands, as well as the mucous glands in the digestive, respiratory, and genitourinary systems. These glands are greatly affected in CF. Their ducts may be obstructed by mucus.

Exocrine pancreatic insufficiency
Insufficient production of digestive enzymes.

Growing from or on the outside.

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Distinctive facial expressions associated with specific medical conditions. 

Factor VIII
A soluble blood protein that forms part of the cascade leading to blood clotting. The gene coding for factor VIII is found on the X chromosome in humans. A mutation in this gene in males leads to the disease Haemophilia A, in which a person's blood does not clot normally.

Factor IX
A soluble blood protein that forms part of the cascade leading to blood clotting. The gene coding for factor VIII is found on the X chromosome in humans. A mutation in this gene in males leads to the disease Haemophilia B, in which a person's blood does not clot normally.

False positive result
A person is identified by a test as having a condition/abnormality when they do not.

False negative result
A person is identified by a test as not having a condition/abnormality, when in fact they do.

Familial hypercholesterolaemia (FH)
An inherited disorder caused by any one of over 300 mutations (defects) in the gene for the low density lipoprotein (LDL) receptor. It is characterised by a total blood cholesterol level of above 7.5 mmol/l or a blood concentration of LDL cholesterol of above 4.9mmol/l (hypercholesterolaemia) combined with the presence of xanthomatosis and premature ischaemic heart disease in the patient or a close relative.

See 'Forced Expiratory Flow Rate'.

Fetal hemoglobin (Hgb.F)
A kind of hemoglobin usually present during fetal (intrauterine) life, which has a different chemical structure from normal adult hemoglobin. After birth, the fetal hemoglobin in the red blood cells is gradually replaced by the adult type of hemoglobin, this process is usually complete during the first 6 months of life.

See 'Forced Expiratory Volume in one second'.

Fibrosing colonopathy
The scarring and narrowing of the large intestine, thought to be related to high doses of some enzymes.

Forced expiratory flow rate
The average flow rate measured over the middle half of the expiration.

Forced expiratory volume in one second
Often abbreviated to FEV1, it is the volume of air one breathes out forcefully in one second after taking a deep breath in. A standard measure of lung function and an efficacy parameter used in CF studies. It is a good predictor of mortality in CF patients.

Forced vital capacity
The total amount of air exhaled forcefully after a deep inspiration.

See 'Functional Residual Capacity'.

Functional residual (reserve) capacity
The amount of air remaining in the lungs after a normal exhalation. It cannot be measured directly. Functional Reserve Capacity is the sum of the Expiratory Reserve Volume and Reserve Volume.

See 'Forced Vital Capacity'.

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A genetic disorder resulting in the impairment of transformation of the simple sugar galactose to glucose.

Gamma-glutamyl carboxylase
An enzyme that catalyses the gamma-carboxylation of glutamic acid residues in bone matrix proteins such as osteocalcin.

Concerning the digestive system, e.g. the stomach, bowel.

Gastrointestinal motility
Normal movement of food through the digestive system.

Gastrointestinal tract
Digestive system.

Gastroesophageal reflux (GOR)
Return flow of the stomach contents into to the oesophagus.

A device permanently placed in the stomach to facilitate supplemental feedings; MIC and Bard buttons are two kinds of buttons.

Gaucher's disease
An inherited metabolic disorder in which harmful quantities of a fatty substance called glucocerebroside accumulate in the spleen, liver, lungs, bone marrow, and, in rare cases, the brain.

The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.

Gene therapy
A form of therapy where a normal, functioning gene is introduced into a cell in which that gene is missing or defective.

Gene transfer
Insertion of unrelated DNA into the cells of an organism. There are many different reasons for gene transfer: for example, attempting to treat disease by supplying patients with therapeutic genes.

Genetic disorder
A condition, which is the result of alterations in the genetic make-up of an individual. They may be the direct consequences of defects in single genes (mutations); or in whole chromosomes, parts of which may be lost, duplicated or misplaced; or from the interaction of multiple genes and external factors.

All the DNA contained in an organism or a cell, which includes both the chromosomes within the nucleus and the DNA in mitochondria.

The genetic identity of an individual that does not show as outward characteristics.

See 'Gastrointestinal'.

A type of glycolipid compound which accumulates in the blood vessel walls of people with Fabry disease as a result of a deficiency in alpha-galactosidase A, a lysosomal enzyme.

Glomerular filtration rate
The volume of fluid filtered from the renal (kidney) glomerular capillaries into the Bowman´s capsule (a cup-like sac at the beginning of the tubular component of a nephron in the mammalian kidney) per unit time.

A capillary tuft surrounded by Bowman's capsule in nephrons of the vertebrate kidney.

A group of anti-inflammatory drugs that are related to cortisol, a natural steroid hormone produced by the body.

Presence of glucose in the urine.

Long unbranched polysaccharides (previously referred to as mucopolysaccharides) consisting of a repeating disaccharide unit which in turn consists of a hexose (six-carbon sugar) or a hexuronic acid, linked to a hexosamine (six-carbon sugar containing nitrogen).

A subtype of glycolipids containing the amino alcohol sphingosine; a ceramide (a sphingolipid) linked to one or more sugars via the terminal hydroxyl group.

Gonadal failure
The condition in which the production of sex hormones and germ cells are inadequate.

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H2 receptor antagonists
Drugs which act by blocking the H2 receptor. In the GI tract the effect of these drugs is to lower gastric acid secretion.

The hematocrit is the percent of whole blood that is comprised of red blood cells. The hematocrit is a compound measure of red blood cell number and size.The hematocrit is almost always included as part of the full blood count (FBC).

A protein found in the red blood cell, two beta, two alpha and four hemes combine to make one haemoglobin molecule. Haemoglobin carries and delivers oxygen to the cells.

Haemoglobin type and description
Hb A: Usual haemoglobin, also called adult haemoglobin.
Hb AA: The inheritance of Hb A from both parents.
Hb S: Sickle Haemoglobin, a beta chain variant.
Hb AS: Sickle cell trait, also known as carrier state. The inheritance of Hb A from one parent and Hb S from the other parent.
Hb SS: Sickle cell anaemia. The inheritance of Hb S from both parents, also known ashomozygous for HbS.

Hb CHaemoglobin C, another beta chain variant.
Hb AC: Hb C trait. The inheritance of Hb A from one parent and Hb C from the other parent.
Hb SC: SC disease. The inheritance of Hb S from one parent and HbC from the other parent, a compound heterozygote condition.
Hb CC: Hb C disease. The inheritance of Hb C from both parents.
Hb A Beta-Thal:Beta-Thalassaemia trait. The inheritance of Hb A from one parent and Hb Beta-Thal trait from the other parent.
Hb S Beta-Thal: Sickle Beta-Thalassaemia. The inheritance of Hb S from one parent and Beta-Thal trait from the other parent, a compound heterozygote state.
Hb A2: An adult haemoglobin usually only present in small amounts but present in increased amounts in Beta-Thalassaemia trait. Quantitation of this haemoglobin can therefore be useful in the diagnosis of this condition.
Hb FFetal haemoglobin which can be raised in Beta-Thal trait and sickle cell disease.

Hemoglobin C trait (AC)
The inheritance of one gene for the usual hemoglobin (A), and one gene for hemoglobin (C). A person who has hemoglobin C Trait (AC) is a carrier of the hemoglobin C gene, and is not affected by the gene.

A group of inherited disorders involving abnormal production or structure of the haemoglobin chains. These disorders include the family of sickle cell disease, haemoglobin C disease, haemoglobin S-C disease, sickle cell anemia (SS), as well as as well as the thalassaemias.

Breaking of the red cell membrane causing release of haemoglobin.

Anaemia due to the abnormal breakdown of red blood cells

An inherited bleeding disorder (also coagulation disorder) caused by low levels, or absence of, a blood protein that is essential for clotting; haemophilia A is caused by a lack of the blood clotting protein factor VIII; haemophilia B is caused by a deficiency of factor IX.

The expectoration or spitting up of blood or bloody mucus from the lungs, throat, or mouth.

A form of iron overload disorder resulting in the accumulation of haemosiderin which is an iron-storage complex.

The arrest of bleeding, either by vasoconstriction, coagulation or by surgical means.

Bad breath.

Heparan sulphate
A linear polysaccharide found in all animal tissues which regulates a wide variety of biological activities, including developmental processes, angiogenesis, blood coagulation and tumour metastasis.

Condition characterized by enlargement of the liver and spleen, caused by intense immunological activity; can occur as a result of mononucleosis infection or acute viral hepatitis, which may indicate a case of lysosomal storage disease. 

A peptide hormone produced by the liver which is involved in the master regulation of iron homeostasis in humans and other mammals.

Used in a general sense to describe the variation in, or diversity of participants, interventions and measurement of outcomes across a set of studies, or the variation in internal validity of those studies.

In genetics having identical alleles for a single characteristic.

Repelled by water.

Hydroxyurea is in a class of drugs known as urea derivatives. In sickle cell anemia, hydroxyurea decreases the episodes of painful crisis by decreasing the sickling of red blood cells.

Increased calcium levels measured in the blood. 

High blood sugar. Can occur in people with CF as a result of diabetes mellitus. This condition is easily controlled through use of insulin.

A higher than normal level of potassium in the blood. 

Hyperosmolar agents
Agents causing the abnormal increase in the concentration of a solution, especially a body fluid, as occurs in dehydration.

Hypertonic saline
Water with a concentration of more than 0.9% (which is isotonic) salt.

High levels of uric acid in the blood.

High levels of uric acid in the urine.

Low calcium levels measured in the blood. 

A substantially decreased ability to sweat.

Breathing that is shallower, and/or slower, than normal.

Abnormally low blood pressure.

Low muscle tone.

Any of several diseases caused by deficiency of one or more vitamins.

Lack of oxygen in the blood which can cause discolouration of the skin or mucuos membranes. May occur in lung diseases such as CF.

A lack of oxygen in the blood - Coalition for pulmonary fibrosis.

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See Inspiratory Capacity

IgE antibodies
A type of immunoglobulin made by the body which are implicated in allergic reactions.

IgG antibodies
A type of immunoglobulin involved in fighting foreign bodies, bacterial and viral infections.

The process of inhibiting a normal immune response with the use of drugs, biological agents, or chemical agents; commonly used in association with tissue transplantation or to control autoimmune diseases.

In vitro
Outside the living body and in an artificial environment

Inborn errors of metabolism
Inherited diseases resulting from alterations in genes that code for enzymes.

An area of tissue death due to a local lack of oxygen.

Inhaled corticosteroids
Inhaled corticosteroids are steroid medicines given into the lungs through an inhaler device, frequently used to treat asthma.
Nasal corticosteroids are steroid medications sprayed into the nose to help relieve the symptoms of conditions such as hay fever.

Inspiratory capacity
Equals the total amount of air you can inhale from a resting exhalation. Another way of looking at inspiratory capacity is:
Tidal Volume + Inspiratory Reserve Volume = Inspiratory Capacity

Inspiratory residual (reserve) volume
Represents the amount of air you can breathe in after a resting inspiration. This is the amount of air volume your body can call upon when a deeper breath is needed during exercise or when your body is under stress. Your body increases respiratory volume when it needs more oxygen and needs to blow off excess carbon dioxide.

Intention-to-treat analysis
A strategy for analysing data from a randomised controlled trial. All participants are included in the arm to which they were allocated, whether or not they received (or completed) the intervention given to that arm. Intention-to-treat analysis prevents bias caused by the loss of participants, which may disrupt the baseline equivalence established by randomisation and which may reflect non-adherence to the protocol. The term is often misused in trial publications when some participants were excluded.

Intercranial hypertension
An increase in the pressure in the brain fluid, called cerebrospinal fluid, above normal.

Intestinal malabsorption
Reduced absorption of nutrients by the small intestine.

Meaning the inside of a bone.

Situated within, performed within, occurring within, or administered by entering a vein.

Iron chelation
The process by which some molecules called chelators bind to iron and remove them as well as neutralise the toxic property (desferrioxamine).

Iron chelating agents
Chemical compounds which form complexes by binding metal ions. Some chelating agents, including desferrioxamine and penicillamine, are drugs used to treat metal poisoning: the metal is bound to the drug and excreted safely. Chelating agents often form the active centres of enzymes.

See 'Inspiratory Residual (Reserve) Volume'.

A low oxygen state, usually due to inadequate blood flow, may be the result of obstruction or low perfusion leading to low oxygen levels in the tissue.

Ischaemic heart disease
Where the heart is damaged by inadequate blood flow.

Isotonic saline solution
A solution of sodium chloride and distilled water having the same concentration of solutes as the blood.

ß-adrenergic receptor stimulants drug.

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A type of enzyme that transfers phosphate groups from high-energy donor molecules, such as adenosine triphosphate (ATP), to specific substrates.

Backward and lateral curvature of the spine.

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Laryngitis is an inflammation of the larynx (voice box), may be caused by infection.

A derivative of the amino acid lysine , required for the transport of fatty acids into mitochondria for oxidation.

A sugar-binding protein located on the surface off cells to allow cells to link to each other.

Left ventricular ejection fraction
The fraction of blood pumped out of the left ventricle with each heart beat.

An abnormal structural change in body tissues or organs. For example, the scar tissue in the lungs of a child with CF.

Leucocyte, Leukocyte
White blood cell, involved in body defence systems.

Fatty molecules which are used by the body for energy. They are an important part of cell structure. People with CF with pancreatic insufficiency lack digestive enzymes responsible for the breakdown of fats into lipids.

A synthetic membrane vesicle made from phospholipids and used for in vitro study of membrane-defined events such as transport, or for the delivery of substances to a cell.

Longitudinal study
Measuring the performance of a sample on more than one occasion over a period of time.

Lower respiratory tract
The part of the respiratory tract situated below the vocal cords.

See 'Lower respiratory tract'.

The phenomenon wherein one of the two copies of the X chromosome present in female mammals is inactivated.

To isolate a solid substance from solution by freezing the solution and evaporating the ice under vacuum.

The breaking down of a cell.

Lysosomal hydrolase alpha-galactosidase
Enzyme involved in glycolipid catabolism, which requires an acidic environment as maintained in the lysosome.

Lysosomal inclusions
Storage bodies associated with lysosomal dysfunction, usually a deficiency of an enzyme involved in catabolism.

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A group of antibiotics including azithromycin, clarithromycin and erythromycin. Erythromycin has a similar spectrum to penicillin and may be used as an alternative to this drug. Azithromycin and clarithromycin have a broader spectrum.

Macrocyclic lactone
Chemical compounds that represent the main treatment for parasitic diseases of animals.

Tending to deteriorate, infiltrate, metastasize and terminate fatally.

Maxillary sinus
An air filled cavity within the maxilla (bone that forms the face and upper jaw). The maxillary sinus is located just below the bony prominence of the cheek.

The first stool of a newborn infant, usually passed within a few hours after birth. Contains mucus and other secretions of intestinal glands.

Meconium ileus
Obstruction of the intestines of a newborn infant with abnormally thick meconium. The earliest symptom of CF, it presents as intestinal obstruction in the neonatal period. It occurs in seven to 10 percent of people with CF.

The growing portion of a long bone which lies between the diaphysis (shaft) and epiphysis (end).

An inner layer of the glomerulus (a tiny ball-shaped structure composed of capillary blood vessels actively involved in the filtration of the blood to form urine) in the kidneys.

The use of statistical techniques in a systematic review to integrate the results of included studies. Sometimes misused as a synonym for systematic reviews, where the review includes a meta-analysis.

Methicillin-resistant Staphylococcus aureus (MRSA)
A bacterial strain that is resistant to methicillin and most other antibiotics.

MIC (Minimum inhibitory concentration)
The lowest concentration of an antibiotic required to inhibit the growth of an organism in vitro.

Average urine albumin-to-creatinine ratio of 30 mg/g to 300 mg/g on two spot urine specimens obtained six months apart. 

An abnormally small head of a newborn, a congenitally small brain.

Microvascular disease
A condition affecting small blood vessels in the body.

Monoclonal antibody
A protein substance which is produced in the laboratory by a single population of cells.



A glycoprotein found especially in the secretions of mucous membranes.

Pertaining or relating to, or resembling mucus.

Mucociliary clearance
Mucociliary clearance of the respiratory tract is an important defence mechanism against inhaled pathogens. Cilia, which line both the upper and lower airways, are covered by a thin layer of mucus, and beat rapidly in a co-ordinated fashion propelling particles trapped in the mucus layer to the pharynx. Defective mucociliary clearance predisposes the respiratory tract to recurrent infection.

Mucolytic agents
Drugs which are used to break down (dissolve, digest,or liquefy) mucus so that it can be coughed up.

Any of a group of lysosomal storage diseases that have in common a disorder in metabolism of mucopolysaccharides; they are identified by the excretion of various mucopolysaccharides in urine and infiltration of these substances into connective tissue, with resulting various defects of bone, cartilage, and connective tissue.

Mucosal oedema
Accumulation of fluid and swelling of any membrane or lining which contains mucous secreting glands.

Term once used for cystic fibrosis. Still used in Europe. Mucoviscidosis was coined in 1944 to describe the abnormally viscid (thick and sticky) mucous secretions characteristic of CF.

The depletion of the bone marrow cells by the administration of high doses of chemotherapy or radiation therapy.

Myocardial infarction
Commonly known as a heart attack, resulting from an interruption of blood supply to part of the heart.

Disease of muscle or muscle tissue, especially skeletal muscle.

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Nasal polyps
Small growths of swollen mucous membrane which project into the nasal passages. Common in children with CF, they maybe multiple or recurrent.

Nasogastric feeding
Feeding through a tube inserted via the nose which reaches down into the stomach.

A device used for generating a mist or aerosol from a solution. In the treatment of CF, nebulisers may be used for delivering aerosol antibiotics, mucolytic or other drugs.

A newborn less than or equal to 28 days of age.

Stones in the kidney. 

Something which damages the kidneys.

Neurologic disease
A disorder of the brain, spinal cord and nerves.

Any disease of the peripheral nerves, usually causing weakness and numbness.

Neuro-psychometric testing
Detailed testing of memory and other aspects of intellectual functioning such as planning, speed of thinking, abstract thinking, calculation, language (including speech and reading), visio-spatial function and attention and concentration. It is often used to assess if there is evidence of intellectual or memory decline. When performed serially (eg at annual intervals) it can be used to detect evidence of change in intellectual functioning with time.

Toxicity to nervous tissue (both brain and peripheral nerves).

Abnormally low number of leukocytes (mainly neutrophils) in the blood, most commonly due to a decreased production of new cells in conjunction with various infectious diseases, as a reaction to various drugs or other chemicals, or in response to irradiation.

A variety of granulocyte (a type of white blood cell) distinguished by a lobed nucleus. It is capable of ingesting and killing bacteria and provides an important defence against infection.

Nitric oxide
An important member of the group of gaseous mediators, which – together with amine mediators (e.g. adrenaline, noradrenaline, histamine, acetylcholine) and lipid mediators (e.g. prostaglandins) – produce many physiological responses. 

Procedure which does not require incision/invasion into the body or the removal of tissue.

Not yet converted into bone.

Nucleoside analogue
A range of antiviral products used to prevent viral replication in infected cells.

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Having to do with the eye

Omega-3 fatty acids - DHA/EPA -
A type of fatty acid found in fish and marine oils which provides the health benefits of reduced risk of cardiovascular disease and improved mental and visual function.

A drug or therapy containing or derived from opium.


The first part of the throat just behind the mouth which connects the mouth to the throat; includes the back of the tongue, the back of the roof of the mouth, tonsils and the back wall of the throat. 

A cell that is responsible for bone formation.

The organic portion of the matrix of bone tissue, when the osteoid becomes mineralised, it and the adjacent bone cells have developed into new bone tissue. 

A disease of adults that is characterized by softening of the bones and is similar to rickets in the young.

Infection of bone, it may remain localised or may spread through the bone.

Reduction in bone volume to below normal levels especially due to inadequate replacement after the normal breakdown of bone.

A condition that affects especially older women and is characterized by decrease in bone mass with decreased density and enlargement of bone spaces producing porosity and brittleness.

Impacting on either hearing or balance or both.

Oximetry measures the percentage of hemoglobin saturated with oxygen by passing specific wavelengths of light through the blood. It includes non-invasive oxygen monitoring by pulse oximetry.

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A tongue-shaped glandular organ lying below and behind the stomach. It secretes the hormones insulin and glucagon (both regulate blood sugar), in addition to pancreatic enzymes involved in the digestion of fats and proteins in the small intestine.

Parametric data
Parametric statistical tests assume that the data are "normally distributed", that is, when graphed, the data follow a "bell shaped curve".

Parenteral nutrition
Nutrition taken intravenously (bypassing the digestive tract) in a hospital, nursing home or patient's home. You may also see the terms TPN (total parenteral nutrition) or HA (hyperalimentation) used.

Abnormal touch sensations, such as burning or prickling, that occur without an outside stimulus.

Parietal cell
One of the cell's of the gastric glands, it secretes hydrochloric acid that reaches the lumen of the gland through fine intracellular and intercellular canals (canaliculi).

A specific causative agent (as a bacterium or virus) of disease.

Peak flow meter
A portable, inexpensive, hand-held device used to measure the flow of air during maximal expiration.

Peak expiratory flow rate
The greatest rate of airflow that can be achieved during forced expiration beginning with the lungs fully inflated.

PEP Device
See 'Positive expiratory pressure device'.

Perineurium cells
Cells forming the middle layer of the protective sheath surrounding peripheral nerves.

Peripheral neuropathy
Any damage to the peripheral nerves (which are the nerves outside the brain and the spinal cord).

Pulmonary Function Test.

The study of the biochemical and physiological effects of drugs and the mechanisms of their actions, including the correlation of actions and effects of drugs with their chemical structure.

The study of the action of the body on drugs over a period of time, including the processes of absorption, distribution, metabolism, localisation in tissues, biotransformation, elimination and excretion.

Pharyngitis is defined as inflammation of the mucous membranes and submucosal structures of the pharynx. There are many agents which cause pharyngitis, the most common being viruses. Common signs and symptoms include sore throat, fever, headache, and nausea and vomiting.

The characteristics displayed by an individual under a particular set of environmental factors, regardless of the actual genotype of the individual.

An inherited autosomal recessive disorder that results from a lack of the enzyme phenylalanine hydroxylase. This leads to accumulation of the amino acid phenylalanine that can impair development of the nervous system and cause neurodevelopmental impairment.

One of the amino acids which the body cannot manufacture itself, but must acquire from food., abundant in meats and cheese. Phenylalanine is a precursor of tyrosine and together they lead to the formation of adrenaline which is converted into a brain chemical which transmits nerve impulses and is used to manufacture noradrenaline which in turn promotes mental alertness, memory, elevates mood and suppresses the appetite.

A form of follicular hyperkeratosis associated with some micronutrient, e.g. vitamin A, deficiencies.

Therapeutics based only on plant material, either from the complete plant or extracts, used for treatment purposes.

Pigmented retinopathy
A disorder of the retina characterized by deposits of pigment and increasing loss of vision.

See 'Phenylketonuria'.

Blood cell with no nucleus that helps to control bleeding by causing clotting; also called thrombocyte.

A condition in which air has entered and expanded the normally closed pleural space, driving pleural pressure up toward atmospheric pressure, and resulting in partial or complete collapse of the lung. Can be a complication of CF.

Pneumococcal prophylaxis
Protective or preventive treatment against a bacterium of the genus Streptococcus (S. pneumoniae) that causes an acute pneumonia involving one or more lobes of the lung.

Polyclonal antibodies
Antibodies that are obtained from different B-cell resources.

Polypeptide hormone
A hormone made up of several amino acids.

Portal bridging
Decaying cells between some areas of liver in chronic liver disease.

Positive expiratory pressure device
Devices which provide a constant back pressure to the airways during expiration.

Portal hypertension
Any increase in the portal vein (in the liver) pressure due to anatomic or functional obstruction (for example alcoholic cirrhosis) to blood flow in the portal venous system.

Postural drainage
The use of gravity assisted positioning to enable clearance of secretions. Also called bronchial drainage.

After a meal.

A glucocorticoid with the general properties of the corticosteroids.

This occurs in Sickle Cell Disease. The continued erection (generally painful) of the penis without sexual desire, occurs when sickle cells block blood circulation in the penis. Stuttering priapism is defined as recurrent episodes of prolonged erections.

Procoagulant factor VIII
A coagulation (clotting) factor. Classic haemophilia (haemophilia A) is due to a congenital deficiency in the amount (or activity) of factor VIII. Factor VIII is also known as antihemophiliac factor (AHF) or antihemophiliac globulin (AHG). See also Factor VIII.

Referring to prevention, such as drugs used to prevent disease or complications.

Average albumin-to-creatinine ratio > 300 mg/g on two spot urine specimens obtained six months apart. 

Prostaglandin E2 analogue
A hormone-like substance which reduces the production of stomach acid and protects the stomach lining, e.g. misoprostol.

The presence of protein in the urine.

An enzyme that digests proteins.

Proton pump inhibitors
A group of anti-ulcer medications which work by binding to an enzyme which is found on the secretory surface of parietal cells. It thereby inhibits the final transport of hydrogen ions (via exchange with potassium) into the gastric lumen and reduces acid secretion, e.g. omeprazole.

Pseudomonas aeruginosa
Bacteria (with a single circular chromosome) which frequently colonise the lungs of people with CF and are a major cause of respiratory infections. Prefer moist environments. Produce a bluish and greenish pigment and have a distinct "fruity" odour. The infection is harmful because the bacteria create toxins and enzymes which destroy the host tissue and cause the complications which are usually associated with cystic fibrosis.

Relating to the lungs.

Pulmonary exacerbations
Acute lung infections.

Pulmonary function tests
Test procedures used to evaluate lung function. Along with patient history and physical examination, pulmonary function tests are used to make the diagnosis, plan therapy, and determine prognosis. Can be used with adults and with children at least five to six years of age. Pulmonary function tests are used to measure: flows (of air) and timed volumes; tidal volume (amount of air entering and leaving the lungs during natural respiration); maximum voluntary ventilation (amount of air forcefully expired during one minute); residual volume of air remaining in the lungs after maximum voluntary expiration); total lung capacity (total amount of air in the lungs after maximum inspiration); and vital capacity (maximum amount of air expired after a full inspiration.) All pulmonary function tests are defined separately in this glossary.

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Quorum sensing inhibitors
Molecules that interrupt the pathway of communication bacteria used to regulate expression of virulence factors.

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Radiographic infiltrates

See 'Crackles'.

Random effects model
A statistical model in which both within-study sampling error (variance) and between-studies variation are included in the assessment of the uncertainty (confidence interval) of the results of a meta-analysis. When there is heterogeneity among the results of the included studies beyond chance, random-effects models will give wider confidence intervals than fixed-effect models.

Recombinant DNA molecule
Recombinant DNA is DNA that has been created artificially. DNA from two or more sources is incorporated into a single recombinant molecule.

Red blood cell dehydration
Loss of water from red blood cells.

Relating to the kidneys.

Respiratory rate
Number of breaths per minute.

RGD peptide mix
Arginine-glycine-aspartic acid (RGD) peptide matrix is designed to act as a temporary, topical synthetic extracellular matrix that substitutes for the damaged natural matrix and provides support for cell ingrowth into the ulcer site. This synthetic matrix consists of an RGD-containing peptide complexed with sodium hyaluronate in a sterile, non preserved viscous gel. 

A disease caused by vitamin D deficiency, characterized by softening and distortion of the bones typically resulting in bow legs.

Ribonucleic acid. Molecules of nucleic acid which are formed in the cell's nucleus (as directed by DNA). RNA is responsible for assembling proteins.

Residual volume
The amount of air left in the lung after you blow out as much air as possible.

To do with the change in form and the flow of matter, including elasticity, viscosity, and plasticity.

See 'Residual Volume'.

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A mixture of salt and water.

See 'Sickle Cell Disease'.

A medical condition in which a person's spine is curved from side to side. 

Examination of a group of usually asymptomatic individuals to detect those with a high probability of having a given disease, typically by means of an inexpensive diagnostic test.

Segmental sclerosis
Scarring or degeneration, often used in relation to disease of a kidney section.

The presence of organisms in the blood.

A condition which follows as a consequence of a disease or another condition.

The development of antibodies in the blood as a result of the introduction of a foreign body, infection or immunization.

The clear, liquid portion of blood which separates in the clotting of blood.

Serum creatinine
A by-product of metabolism that is measured in serum as a indicator of kidney function.

Serum ferritin
An indirect measure of iron in the blood.

Shwachman-Kulczycki score
A general score of clinical severity in cystic fibrosis assessed at annual review. Score separately each of the 4 areas (general activity, physical examination, nutrition and X-ray findings).

Sickle cell anaemia
A condition caused by a mutation in the beta globin gene leading to production of abnormal haemoglobin. This causes the red blood cells to take on a distorted 'sickle' shape which severely reduces oxygen carrying capacity. Sickle cell anaemia is inherited from both parents as an autosomal recessive trait.

Sickle cell disease (SCD)
An inherited disorder of the red blood cells in which one gene is for sickle haemoglobin (S), and the other gene is for another unusual haemoglobin such as S, C, Beta Thalassaemia. etc. The following are examples of sickle cell disease: SS, SC, SD, SßThal, etc. It is seen most commonly in people of African, Mediterranean, Arabian and Indian ancestry. The family of clinically significant disorders including SS and compound heterozygote conditions.

Sickle cell retinopathy
People with sickle cell disease may develop sickle cell retinopathy, which can occasionally lead to blindness. This condition manifests slowly and rarely occurs before the age of ten years. Sickle cell retinopathy is more common in those with Hemoglobin SC disease than SS.

Sickle cell trait (AS)
The inheritance of one gene for the usual haemoglobin (A) and one gene for sickle haemoglobin (S). A person who has sickle cell trait (AS) is a carrier of the sickle gene, does not have the disease, does not have painful episodes, and is rarely affected by the sickle haemoglobin.

Inflammation of a sinus or cavity.

Skeletal dysplasia
Disorders in bone and cartilage development causing deformities such as duplication of fingers or toes, affecting growth of the limbs, or even their absence; more than 175 different types of bone dysplasias are known and most of them are caused by genetic mutations. 

Skin excoriation
Abrasion or wearing off the skin.

Slipped capital epiphyses
Orthopedic condition in which the growth center of the hip (the capital femoral epiphysis) slips backwards on the top of the femur (the thighbone).

The surgical removal of the spleen.

Splenic sequestration
Young children with SCD may have episodes of blood pooling in the spleen dropping Hb ³2, which may be life threatening.

Enlargement of the spleen. 

Instrument used to measure lung air volumes and flow rates.

Spirometric lung function
The vital capacity of the lungs, or the volume of air which can be expelled from the chest after the deepest possible inspiration.

Mucus and other materials coughed up from lungs. Phlegm.

Standard deviation
A measure of the spread or dispersion of a set of observations, calculated as the average difference from the mean value in the sample.

Staphylococcus aureus
Bacterial infection which most commonly inhabits the human nasal cavity. They occur in regular, grapelike clusters. Characteristic symptoms are pus filled inflammatory regions called abscesses. This same bacterium also causes Toxic Shock Syndrome and some types of food poisoning. In CF, "staph" commonly causes respiratory infections. Can often be effectively treated with antibiotics.

Faecal matter that is frothy, foul-smelling and floats because of a high fat content. In cystic fibrosis, this is caused by blockage of pancreatic ducts. Fats are not properly broken down and absorbed and are therefore excreted in the stools.

A sudden attack of weakness or paralysis affecting a part (generally one side) of the body that lasts ³ 24 hours. It is usually caused by a disruption of blood flow to a region of the brain. A stroke can range in severity from those that recover to severe paralysis, coma or death.

An early stage or mild form of a medical condition, where no symptoms are detectable.

Subcutaneous bleeding
Bleeding under the skin.

A molecule that is acted upon by an enzyme.

Sweat electrolytes
Chemical ions contained in sweat. Some electrolytes (sodium and chloride) are elevated in most people with CF.

Sweat test
The diagnostic test for CF. Measures the concentration of salt (sodium and chloride) in sweat which are elevated in CF.

Interaction of discrete agents (such as drugs) such that the total effect is greater than the sum of the individual effects. 

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Cells which belong to a group of white blood cells known as lymphocytes, and play a central role in cell-mediated immunity.

The excessive rapidity in the action of the heart, the term is usually applied to a heart rate above 100 per minute.

An abnormally rapid respiratory rate.

Is one of the most abundant amino acids in the body. It is found in the central nervous system, skeletal muscle and is very concentrated in the brain and heart. Taurine seems to inhibit and modulate neurotransmitters in the brain.

A muscular twitching disorder associated with low calcium in the blood.

A group of inherited blood disorders resulting from reduced or absent production of globin chains for the haemoglobin molecule in red blood cells. This leads to mild to severe anaemia. Other symptoms may include an enlarged spleen and anormalities in the bone marrow. Severe cases of the disease occur in patients who have both Beta globin genes mutated. Carriers (trait or Heterozygotes) are only mildly affected or have no symptoms at all. The Thalassaemias are widespread in Mediterranean countries, Asia and Africa.

Thalassaemia intermedia
When two Beta Thalassaemia genes have been inherited but the patient only requires infrequent transfusions.

(Beta) Thalassaemia major
An inherited disease with little or no beta haemoglobin production that requires lifelong red cell transfusions.

Thalassaemia minor (trait)
Reduced production of haemoglobin chains that is sometimes inherited along with sickle haemoglobin to produce sickle-beta thalassaemia. Having the trait by itself, is not harmful.

The blocking of a blood vessel by a blood clot dislodged from its site of origin.

Thrombotic episodes
The formation, presence, or development of a blood clot. 

Tidal volume
While at rest our normal breath is called the Tidal Volume. Stress, exercise, and illness (including asthma) will cause this volume to increase or decrease.

See 'Total Lung Capacity'.

Total lung capacity
The total maximum amount of air your lungs can hold. It is the total of all lung volumes or lung capacities.

Tracheobronchial clearance
Clearance of the trachea and bronchi.

Transcranial doppler ultrasonography
A technique used to measure the velocity of blood flow in the arteries supplying the brain

Entering through the dermis or skin, as in administration of a drug applied to the skin in ointment or patch form.

The conversion of one type of energy or signal into another;in genetics the introduction of DNA into a different cell type, to induce the formation of the corresponding gene product.

A combination of glycerol and three fatty acids (i.e., body fat).

See 'Tidal Volume'.

One of the twenty amino acids directly coded in proteins, can normally be synthesised from phenylalanine.

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Ursodeoxycholic acid
Used in the treatment of gallstones. It is taken by mouth to dissolve the gallstones It is also used to help prevent gallstones in patients who are on rapid weight-loss programs.

Urinary albumin
The presence of albumin, a protein, in the urine.

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Narrowing of the blood vessels. 

Widening of the blood vessels.

Blockage of arteries.

Venous access devices
Catheters placed directly into the venous system for infusion therapy and/or phlebotomy.

See 'Vital Capacity'.

Collection of blood specimen from a vein for laboratory testing.

Viral vectors
Gene delivery systems that use viruses to transfer gene to cells.

Virulence factor
A substance produced by a pathogen that promotes its ability to cause disease.

Vital capacity
Represents the total amount of air exhaled from a maximal inhalation to a maximal exhalation, i.e.TLC & RV.

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Deposits of cholesterol in the tendons and skin.

Abnormal dryness, as of the skin or eyeball.

Relating to genes or characteristics or conditions carried on the X chromosome.

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Zinc sulfate
A salt of zinc used as a supplement for treating zinc deficiency 

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