salvage therapy

Any treatment regimen used after a number of earlier regimens have failed.

seborrhoeic dermatitis

(seb-or-ree-ic der-mah-tyte-uss)

A chronic inflammatory disease of the skin, characterised by dry, moist or greasy scaling, and yellow crusted patches.

sepsis

(sep-siss)

The presence of pus-forming bacteria in the body.

seroconversion

(sear-row-con-ver-shun)

The time at which a person's antibody status changes from negative to positive.

seronegative

Negative antibody result in a blood test.

seropositive

Positive antibody result in a blood test.

serum

(sear-um)

Clear, non-cellular portion of the blood, containing antibodies and other proteins and chemicals.

shingles

Condition caused by a herpes virus infection, involving painful blisters on the skin.

sigmoidoscopy

(sig-moyd-os-ko-pee)

Examination of the rectum and lower bowel with a flexible viewing device.

simian

(sim-ee-un)

Related to or affecting monkeys.

single blind

A type of clinical trial in which the participants do not know what treatments they are getting, but their doctors do.

sinusitis

(sign-uss-ite-uss)

Inflammation or infection of the sinuses, which are cavities behind the forehead and cheekbones.

speculum

(speck-you-lum)

An instrument for enlarging the opening of any canal or cavity in order to inspect its interior, e.g. vagina, rectum, ear or nose.

spleen

Organ which produces white blood cells and acts as a reservoir for red blood cells.

splenomegaly

(splen-o-meg-a-lee)

Enlarged spleen.

sputum smear

(spew-tum smear)

A diagnostic test in which a sample of spit is examined under the microscope for the presence of micro-organisms.

squamous intraepithelial lesion (SIL)

(skway-muss in-tra-epp-ee-theel-ee-ul lee-shun)

Cancerous growth within the cells lining the cervix. Untreated, it can lead to invasive cancer of the cervix.

steroids

Drugs used to damp down excessive immune responses.

strain

A variant characterised by a specific genotype.

subcutaneous

(sub-kew-tay-nee-uss)

Beneath or introduced beneath the skin, e.g. a subcutaneous injection is an injection beneath the skin.

subtype

Different strains of HIV which can be grouped according to their genes. HIV-1 is classified into three ‘groups,’ M, N, and O. Most HIV-1 is in group M which is further divided into subtypes, A, B, C and D etc. Subtype B is commonmest in the UK, Europe and North America, whilst A, C and D are most important worldwide.

superinfection

When somebody already infected with HIV is exposed to a different strain of HIV and becomes infected with it in addition to their exisitng virus.

surrogate marker

An indirect indicator of something, such as measuring viral load to assess the treatment effect of a drug.

symptom

A condition that results from or accompanies an illness or disease.

symptomatic

Having symptoms.

syndrome

A group of symptoms and diseases that together are characteristic of a specific condition.

synergy

(sin-er-gee)

When two or more drugs produce an effect greater than adding their separate effects.

systemic

(siss-tem-ick)

Acting throughout the body rather than locally.