Findings that may indicate treatment failure in a patient with schistosomiasis:
(1) an elevated eosinophil count in the peripheral blood (in the absence of another explanation)
(2) an elevated serum IgE (in the absence of another explanation)
(3) rising titers of antibodies to schistosomal antigens (presence of stable or falling titers can be expected with treated schistosomiasis)
(4) shedding of viable schistosome eggs in the urine
(5) presence of viable eggs in a rectal biopsy
(6) clinical symptoms consistent with schistosomiasis (abdominal pain, flank pain, loose stools, blood in stool)
where:
• Nonviable eggs may be found in urine or rectal biopsy for some time after successful treatment.
A patient with suspected treatment failure:
(1) should receive a second course of therapy (such as praziquantel)
(2) should have a followup examination 3 to 6 months later
