Trichuriasis (Whipworm)

Key Features

• Trichuris trichiura is a widespread human and animal parasite common in children living in warm, humid areas conducive to survival of the ova

• Ingested infective eggs hatch in the upper small intestine

• Adult worms live in the cecum and colon; the ova are passed and become infectious after several weeks in the soil

• Unlike Ascaris, Trichuris does not have a migratory tissue phase

Clinical Findings

• Symptoms are not present unless the infection is severe, in which case pain, diarrhea, iron deficient anemia, and mild abdominal distention are present

• Massive infections may also cause rectal prolapse and dysentery

Diagnosis

• Detection of the characteristic barrel-shaped ova in the feces confirms the diagnosis

• Adult worms may be seen in the prolapsed rectum or at proctoscopy; their thin heads are buried in the mucosa, and the thicker posterior portions protrude

• Mild to moderate eosinophilia may be present

Treatment

• Mebendazole (100 mg orally twice a day for 3 days) or albendazole (400 mg in a single dose for 3 days, or 200 mg in children 1–2 years of age) tends to improve gastrointestinal symptoms