Thread by @IUIDfellowship

#idboardreview 40 M travel to Uganda, Kenya & Tanzania, swam/rafted in Nile & Lake Victoria presents w/ 5d of headache, now w/ seizure, took all travel vaccine/prophylaxis, ate cooked meals, no eosinophilia, CXRneg, LPneg. diagnosis? #medEd #idmedEd

#Neuroschistosomiasis

In tropical or subtropical setting, a seizure associated w/ a focal lesion in brain is most often due to cysticercosis caused by the pork tapeworm, Taenia solium. Cysticercosis occurs in East Africa but is not nearly as common there as it is in Latin America, including Mexico

Cysticercosis doesnt match in this case as larva in cysticercosis evokes little/no inflammatory response/edema in early stages & wont cause seizure earlier. It takes 2mo to form thin cavity w/scolex. 1yr later: cause inflammatory response: later calcify & seizure develops

DDx: cestodes echinococcus (brain involvement is rare & should have pulmonary involvement with it) Taenia multiceps (similar to cysticercosis but rare) & spirometra (pt didnt have skin nodules)

DDx: fluke: Paragonimus: round, focal, granulomatous lesion in brain, which is the most common extrapulmonary site of infestation, but this pt had absence of lung lesions. Also mostly in W Africa & Far East

#Schistosomiasis:swim/raft in Nile & Lake Victoria; warm, fresh-water +snail hosts of schistosomes. Entry is transdermal can go unnoticed(swimmer's itch). A pair of flukes mate & release eggs in bloodstream; spread to other parts including brain

S. mansoni & S. haematobium ubiquitous in Africa. Can rarely cause CNS lesions brain/spinal cord

pt had brain biopsy: necrotizing granuloma surrounding a refractile ovum of S. mansoni, identified by presence of a prominent lateral spine

pathologic response to #schistosoma ova in CNS varies, depending on intensity of infection & host's immunologic status (no tissue reaction or only scant inflammatory reaction to scattered ova, localized vasculitis, or most commonly tissue necrosis with the formation of granulomas

Treatment: praziquantel

nejm.org/doi/full/10.10…