[A woman with long-lasting diarrhoea and fatigue]

Intestinal trematodes are common parasites in man and many mammals. Infection is often asymptomatic and unrecognised.

A woman in her twenties presented with loose stools of variable intensity over six months. Additionally, she had experienced considerable fatigue during this period. There was no weight loss and initial blood tests were normal. Further testing at the second visit included stool microscopy, and small trematode eggs consistent with H. heterophyes infection were found. A more thorough anamnesis revealed the onset of symptoms on the day she returned from a week's holiday, and the probable exposure occurred from eating sushi twice during this holiday. After one day of treatment with praziquantel 40 mg/kg administered in three doses, the patient recovered completely within two to four weeks. Her asymptomatic partner had consumed the same food and had the same eggs in his stool sample. He was successfully treated with the same treatment dose.

A detailed travel history may provide important information relating to the diagnosis of diarrhoea and fatigue. Symptoms of H. heterophyes infection are variable. A single day's dose of 40 mg/kg of praziquantel was sufficient to eradicate infection in the two cases presented.