skip to main content

PML — SCE Infectious Diseases MCQ

Instant feedback + full explanation. One question, done properly.

ModerateHIV MedicinePMLSCE Infectious Diseases

A 50-year-old man with HIV (CD4 60, not on ART) develops progressive cognitive decline, ataxia, and personality change over 3 months. MRI shows diffuse white matter signal abnormality without enhancement or mass effect. CSF is acellular with normal glucose and protein. What investigation should be sent on the CSF?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: A — JC virus PCR

Progressive cognitive decline with diffuse white matter changes without enhancement in advanced HIV is classic for progressive multifocal leukoencephalopathy (PML). CSF JC virus PCR is the diagnostic test (sensitivity ~75–90%, specificity >95%). Normal CSF biochemistry and cell count are typical. MRI characteristically shows multifocal, asymmetric white matter lesions without mass effect. There is no specific antiviral; immune reconstitution with ART is the only effective intervention.

Reference: BHIVA 2022 – OI guidelines; NICE 2024 – CNS infections in immunosuppression