Question
A 30-year-old truck driver presented with diarrhoea of one-month duration. He gives history of multiple exposure with commercial sex workers
- (a) What is your provisional diagnosis 1 mark(s)
- (b) Name two opportunistic parasites responsible for diarrhoea in this patient 2 mark(s)
- (c) How do you confirm the diagnosis according to NACO strategy 4 mark(s)
- (d) Name two other opportunistic infections which this patient can have e) Name the cell which is destroyed by this virus 2 mark(s)
Answer
a) Provisional diagnosis: AIDS (HIV infection) — chronic diarrhoea of one month’s duration in a patient with a history of multiple high-risk sexual exposures is classical of advanced HIV disease.
b) Two opportunistic parasites causing diarrhoea in this patient: Cryptosporidium parvum and Isospora (Cystoisospora) belli (Microsporidia is another valid example).
c) Confirmation of diagnosis according to NACO strategy NACO (National AIDS Control Organisation) uses a three-test strategy (Strategy III) for individual HIV diagnosis: three different tests/kits, based on different antigen preparations or test principles, are used serially — a sample is tested first with a highly sensitive test, and only if reactive is it tested with a second, different test, and if that is also reactive, with a third, different test. A sample must be reactive on all three tests before HIV infection is confirmed and reported to the individual — this stringent, multi-test approach minimizes the risk of a false-positive diagnosis being communicated, given the serious psychosocial and medical consequences of an incorrect positive result. (Strategy I, using a single test, is used for blood/organ donor screening; Strategy II, using two tests, is used for unlinked anonymous surveillance — neither is used for individual diagnostic confirmation.)
d) Two other opportunistic infections this patient can have: Pneumocystis jirovecii pneumonia (PCP) and oral/oesophageal candidiasis (Candida albicans) — (other valid examples: cryptococcal meningitis — Cryptococcus neoformans; toxoplasma encephalitis — Toxoplasma gondii; disseminated Mycobacterium avium complex).
e) Cell destroyed by this virus: CD4+ T-helper lymphocytes (HIV uses the CD4 receptor, along with a chemokine co-receptor — CCR5 or CXCR4 — for entry, and progressively destroys these cells, causing the immunodeficiency characteristic of AIDS).