Evaluation of new anti-infective drugs for the treatment of diarrhea caused by Entamoeba histolytica. Infectious Diseases Society of America and the Food and Drug Administration

Nitazoxanide in the treatment of amoebiasis

Amoebiasis is a significant cause of morbidity worldwide and is the third leading cause of death from parasitic diseases. This study evaluated nitazoxanide, a thiazolide anti-infective, in the treatment of intestinal and hepatic amoebiasis. Prospective, randomised, double-blind, placebo-controlled studies were conducted in outpatients with intestinal amoebiasis from the Nile Delta of Egypt. Nitazoxanide was administered twice daily for 3 days at doses of 500mg (age > or =12 years), 200mg (age 4-11 years) or 100mg (age 1-3 years). Seventeen adults hospitalised with hepatic amoebiasis were treated with 500mg nitazoxanide twice daily for 10 days. Four days after completion of therapy, 32 (94%) of 34 nitazoxanide-treated patients with intestinal amoebiasis resolved symptoms compared with 15 (50%) of 30 patients who received placebo (P<0.001). Thirty-two (94%) of 34 nitazoxanide-treated patients were free of Entamoeba histolytica in two post-treatment stool specimens compared with only 13 (43%) of 30 patients receiving placebo (P<0.0001). All patients with hepatic amoebiasis responded to nitazoxanide therapy. Nitazoxanide is effective in treating invasive intestinal amoebiasis and in eliminating E. histolytica colonisation of the intestinal tract. Further studies are warranted in patients with hepatic amoebiasis.

Parasites and Diarrhea. I: Protozoans and Diarrhea

Intestinal parasitism is extremely common, with approximately 70% of all people harboring one or more intestinal parasite. Parasitism and diarrhea are both hyperendemic in areas where sanitation is suboptimal. Many clinicians assume that the identification of intestinal parasites in patients with diarrhea implies that the parasites are the cause. This approach is frequently misguided. Some intestinal parasites such as Giardia lamblia and Entamoeba histolytica certainly do cause diarrhea. Others, for example Entamoeba coli and Ascaris lumbricoides, almost certainly do not. In addition, there are a number of other organisms that have been associated with diarrheal illness in some cases, which may or may not be important pathogens. In this article, we will review the role of protozoans as definite and possible causes of diarrhea. In Part II, we review the role of helminths in diarrhea.