Case presentation (Dr B Peters)

A 40 year old heterosexual black African man presented to the accident and emergency department with a 4 minute episode of loss of consciousness with associated incontinence. On inquiry, he gave a 1 month's history of left sided headache, weight loss, fever, and a right axillary swelling. He had a medical history of recurrent malaria, typhoid as a child, drainage of groin abscess in 1999, and severe acne. An HIV antibody test had been negative in 1993. On admission he was taking ciprofloxacin 500 mg twice daily, prescribed by a primary care physician as treatment for the axillary infection; he had recently completed a course of isotretinoin as treatment for acne. He worked as a delivery driver, drank no alcohol, and was a non-smoker. He had been resident in the United Kingdom for 7 years.

On examination he was pyrexial, temperature 38.5°C, had oral candida, severe acne, and a 4 cm diameter infected sebaceous cyst in the right axilla. There was no lymphadenopathy and examination of the respiratory, cardiovascular, abdominal, and nervous systems was normal.

Investigations on admission to hospital included a computed tomograph (CT) scan of the head (with contrast) which showed a single ring enhancing lesion in the left basal ganglia with surrounding oedema and mid-line shift. A diagnosis of cerebral toxoplasmosis was made. Subsequently, an FDG PET (positron emission tomography) scan and cranial magnetic resonance image (MRI) supported this diagnosis. Other investigations showed HIV-1 antibodies detected, cytomegalovirus IgG positive, DAT negative, Toxoplasma gondii IgG > 1:1024, serum cryptococcal latex agglutination (CRAG) …