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Essentials of Diagnosis
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History of freshwater exposure in an endemic area
Acute schistosomiasis: fever, headache, myalgias, cough, urticaria, diarrhea, and eosinophilia
Intestinal schistosomiasis: abdominal pain, diarrhea, and hepatomegaly, then anorexia, weight loss, and portal hypertension
Urinary schistosomiasis: hematuria and dysuria, then hydronephrosis and urinary infections
Diagnosis: characteristic eggs in feces or urine; biopsy of rectal or bladder mucosa; positive serology
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General Considerations
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Intestinal schistosomiasis, with infection of mesenteric venules, caused by
Schistosoma mansoni, which is present in Africa, the Arabian peninsula, South America, and the Caribbean
Schistosoma japonicum, which is endemic in China and Southeast Asia
Schistosoma mekongi, which is endemic near the Mekong River in Southeast Asia
Schistosoma intercalatum and Schistosoma guineensis, which occur in parts of Africa
Urinary schistosomiasis, with infection of venules of the urinary tract
Transmission is focal, with greatest prevalence in poor rural areas
Humans are infected with schistosomes after contact with freshwater containing cercariae released by infected snails
Chronic infection can result in scarring of mesenteric or vesicular blood vessels, leading to portal hypertension and alterations in the urinary tract
Acute schistosomiasis
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Affects more than 200 million persons worldwide, leads to severe consequences in 20 million persons and about 100,000 deaths annually
Prevalence of infection and illness typically peaks at about 15–20 years of age
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