1st August 2023

A 49-year-old man presents to his GP, having returned from a geological expedition in Brazil.

A 49-year-old man presents to his GP, having returned from a geological expedition in Brazil. He has been feeling feverish and lethargic, has been having diarrhoea, and has not had an appetite. He had all his recommended travel vaccinations and was fastidious with his malaria prophylaxis. His background includes Crohn’s disease, for which he has regular infliximab infusions.

On examination, he has a large palpable spleen.

What is the most likely diagnosis?

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