Cryptosporidiuminfection after renal transplantation in an endemic area

Cryptosporidium parvum, a leading cause of persistent diarrhea in developing countries, is a major threat to the U.S. water supply. Able to infect with as few as 30 microscopic oocysts, Cryptosporidium is found in untreated surface water, as well as in swimming and wade pools, day-care centers, and hospitals. The organism can cause illnesses lasting longer than 1 to 2 weeks in previously healthy persons or indefinitely in immunocompromised patients; furthermore, in young children in developing countries, cryptosporidiosis predisposes to substantially increased diarrheal illnesses. Recent increased awareness of the threat of cryptosporidiosis should improve detection in patients with diarrhea. New methods such as those using polymerase chain reaction may help with detection of Cryptosporidium in water supplies or in asymptomatic carriers. Although treatment is very limited, new approaches that may reduce secretion or enhance repair of the damaged intestinal mucosa are under study.

The aim of this study was to evaluate the efficacy of nitazoxanide for the treatment of diarrhea and enteritis caused by Cryptosporidium species in patients 12 years of age and older. A multicenter, randomized, double-blind, placebo-controlled study was conducted in 90 outpatients 12 years of age and older from the Nile Delta region of Egypt. Patients were randomized to receive either one 500 mg tablet or one matching placebo tablet, or 25 mL of nitazoxanide oral suspension (500 mg nitazoxanide), each given twice daily for 3 days. Clinical and microbiologic response rates were evaluated 4 days after completion of treatment. Twenty-seven (96%) of the 28 patients receiving nitazoxanide tablets responded clinically compared with 11 (41%) of 27 patients who received placebo (P < .0001). Twenty-six (93%) of the 28 patients who received nitazoxanide were free of Cryptosporidium oocysts in each of 2 posttreatment stool samples compared with only 10 (37%) of 27 patients who received placebo (P < .0001). Response rates in patients receiving the tablets and the suspension were comparable (clinical response rate for suspension, 27 of 31 [87%]; microbiologic response rate for suspension, 28 of 31 [90%]). These findings show that a 3-day course of nitazoxanide is effective in treating diarrhea and enteritis caused by Cryptosporidium in nonimmunodeficient patients 12 years of age and older.