TRICHURIASIS : CLINICAL ASPECTS
Light infections are asymptomatic. With moderate worm loads, damage to the intestinal mucosa may induce nausea, abdominal pain, diarrhea, and stunting of growth. Occasionally, a child may harbor 800 worms or more. In these situations, the entire colonic mucosa is parasitized, with significant mucosal damage, blood loss, and anemia. The shear force of the fecal stream on the bodies of the worms may produce prolapse of the colonic or rectal mucosa through the anus, particularly when the host is straining at defecation or during childbirth.
In light infections, stool concentration methods may be required to recover the eggs. Such procedures are almost never necessary in symptomatic infections, as they inevitably pro-duce more than 10,000 eggs per gram of feces, a density readily detected by examining 1 to 2 mg of emulsified stool with the low-power lens of a microscope. A moderate eosinophilia is common in such infections.
Infections should not be treated unless they are symptomatic. Mebendazole is the drug of choice; albendazole is thought to be equally effective. Although the cure rate is only 60 to 70%, more than 90% of the adult worms are usually expelled, rendering the patient asymptomatic. Prevention requires the improvement of sanitary facilities.