16th August 2024

A 35-year-old man from Eastern Europe is seen in Ambulatory Care, having been referred by his GP

A 35-year-old man from Eastern Europe is seen in Ambulatory Care, having been referred by his GP with headache and weight loss.

On review in clinic, he reports some headaches worsening over the last few weeks, increasingly associated with lethargy and drowsiness. He reports that he sometimes becomes muddled and this is very unusual for him. He has also had a dry cough worsening over a similar time and reports night sweats. He has lost 9 kg in weight in the last 2 months.

He does not drink alcohol. He has some medication prescribed by a doctor in his home country, which he does not take as he feels it gives him diarrhoea, and has brought a box of expired emtricitabine.

On examination, he is flushed and febrile. There are right-sided coarse crackles. No focal neurological deficit is identified, but there is nuchal rigidity. His AMTS score is 6/10.

Which single investigation is most likely to lead to a definitive diagnosis?

Select the SINGLE most appropriate option from the list below. Select ONE option only.