- abdomen
Stomach (belly) area. The word ‘abdominal’ relates to
pain or other problems in that area.
- abscess
A collection of pus formed as the product of infection.
- absolute risk
The
chance that a person will experience a specific event during a period of time. It
is always between 0 and 1 (when expressed as a probability), or between 0 and
100 (when expressed as a percentage). See also ‘relative risk’.
- absorption
The process (or rate)
of a drug entering the blood.
- acute infection
In
hepatitis, the first six months of infection. See also ‘chronic infection’.
- adherence
The act of taking a treatment exactly as prescribed.
- adverse event
An unwanted side-effect of a treatment.
- AIDS
Acquired Immune Deficiency Syndrome. A collection of specific
illnesses and conditions which occur because the body's immune system
has been damaged by HIV.
- alanine transaminase (ALT)
ALT
is an enzyme found in the liver that helps the body metabolise protein. When
the liver is damaged, ALT is released into the bloodstream, resulting in elevated enzymes in blood tests.
- albumin
A protein made in the liver, needed to maintain a balance of the fluids in the body. In a blood test, lower than normal levels of albumin and total protein may indicate liver damage or disease. If there is not enough albumin, fluid may accumulate in the abdomen (ascites).
- alkaline phosphatase (ALP)
ALP is an enzyme in the liver, bile ducts and bone. When the bile ducts in the liver are obstructed, ALP is released into the bloodstream, resulting in elevated enzymes in blood tests.
- alpha-fetoprotein (AFP)
A protein found in the blood, used to detect early signs of liver cancer.
- amylase
An enzyme produced in the pancreas and saliva which assists in the digestion of starch.
- anabolic
The metabolic processes that build new tissues.
- anaemia
A shortage or change in the size or function of red blood cells.
These cells carry oxygen to organs of the body. Symptoms can include shortness
of breath, fatigue and lack of concentration.
- anal intraepithelial neoplasia (AIN)
An abnormal growth on the surface of the rectum or anal canal which,
when observed with a microscope, suggests that the cells could be
malignant.
- anergy
Lack
of reaction by the body's defence mechanisms when foreign substances come into
contact with the body. This may indicate the inability of the immune system to
mount a normal allergic response.
- anonymised data
Information
about a patient from which the name, address and other identifying information
has been removed.
- anorexia
Loss
of appetite.
- antenatal
Before
birth.
- antibiotic
A
drug that affects bacteria.
- antibody
Protein
substance produced by the immune system in response to a foreign organism.
- anticoagulants
Drugs that prevent the clotting of blood.
- anticonvulsant
Drug used to prevent seizures (fits).
- antigen
Something the immune system can recognise as 'foreign' and attack.
- anti-HBc (hepatitis B core antibody)
Antibody produced by the immune system to fight off hepatitis B. This antibody can only be found in persons who are, or were, infected with hepatitis B. It is not found in healthy vaccinated people.
- anti-HBs (hepatitis B surface antibody)
Antibody produced by the immune system to fight off hepatitis B. A person testing positive for anti-HBs
has usually been vaccinated, or has successfully fought off an earlier infection, and is now protected against HBV.
- antihistamine
Drug
used to treat a number of allergic
health conditions.
- antioxidant
A vitamin, mineral or drug which can reduce the
activity of free radicals, the unpaired electrons produced as a consequence of
burning energy in a cell.
- antiretroviral
A substance that acts against retroviruses such as HIV.
- antiviral
A drug that acts against viruses.
- anxiety
A feeling of unease, such as worry or fear, which
can be mild or severe.
- arthralgia
Pain in the joints.
- arthritis
Inflammation in the joints.
- ascites
An accumulation of fluid in the abdomen; may be caused by liver damage, especially cirrhosis.
- aspartate transaminase (AST)
AST
is an enzyme found in the liver that helps the body metabolise aspartate (a salt). When the liver is
damaged, AST is released into the bloodstream, resulting
in elevated enzymes in blood tests.
- assay
A
test used to measure something.
- association
When
there is a statistical relationship between two variables. For example, when A
increases, B increases. An association means that the two variables change
together, but it doesn't necessarily mean that A causes B. The relationship
isn't necessarily causal.
- asymptomatic
Having no symptoms.
- ataxia
A lack of muscular co-ordination.
- atherogenic
Producing the most degenerative changes in artery walls.
- atherosclerosis
Hardening and narrowing of the arteries.
- atrophy
Wasting due to nutritional imbalance, e.g. due to absorption problems caused by chronic diarrhoea.
- autonomic nervous system
The part of the nervous system that controls involuntary bodily actions.