A previously healthy toddler in Washington state died after an ultra-rare brain infection caused by amoebas was initially mistaken for an inflammatory blood-vessel disease. His doctors later published the case to highlight how an unusual presentation and early misdiagnosis delayed recognition for more than 30 days, leaving him with irreversible brain damage.

The infection has been recorded in only about 200 people worldwide since 1986 and is fatal in roughly 90 per cent of cases. Early scans showed brain bleeding and narrowed or blocked arteries, leading doctors to diagnose childhood Takayasu arteritis and give immunosuppressants; after temporary improvement, the child deteriorated and was eventually taken off life support, with an autopsy finding extensive brain damage and amoebas.