Schistosomiasis is an important parasitic disease, occurring in more than 200 million people worldwide.162 Schistosomes are trematodes with a complicated life cycle. Humans are the definitive hosts; snails are intermediate hosts.

Clinical manifestations of schistosomiasis occur in three phases:

  1. dermatitis
  2. fever (Katayama fever, a serum sickness reaction to schistosomal antigens)
  3. chronic schistosomiasis, potentially involving multiple organ systems, including the CNS

CNS schistosomiasis usually follows egg migration into the brain or spinal cord vasculature, leading to microinfarction or granuloma formation.178 Neurologic manifestations are rare, occurring in only 1– 2% of cases, but they can include a wide range of focal and nonfocal CNS symptoms, including seizures.179

Diagnosis

Diagnosis is by history and supporting lab data, including blood and CSF eosinophilia, and fecal and urine analysis for schistosome eggs. The most specific test is serologic enzyme-linked immunoassay (ELISA) directed against parasite antigens. Neuroimaging can demonstrate cerebral edema and multiple focal lucencies.162

Treatment

Neurologic disease during Katayama fever responds to steroids with or without antischistosomal therapy.162 Cerebral schistosomiasis may require surgical resection of granulomalike masses. Praziquantel is the primary antischistosomal agent. Antiepileptic drugs are used as needed.

Adapted from: Goldstein MA and Harden CL. Infectious states. In: Ettinger AB and Devinsky O, eds. Managing epilepsy and co-existing disorders. Boston: Butterworth-Heinemann; 2002;83-133.
With permission from Elsevier (www.elsevier.com). 

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Reviewed By: 
Steven C. Schachter, MD
on: 
Sunday, February 29, 2004