Etiology of diarrhea in patients undergoing allogeneic bone marrow transplantation in South India.

BACKGROUND No studies so far have examined enteric infections in patients undergoing bone marrow transplantation (BMT) in developing countries where asymptomatic carriage and colonization with enteric pathogens is frequent. METHODS A prospective study followed 65 patients who underwent BMT in South India between 1995 and 1998. Patients were screened for enteric pathogens before transplantation, weekly during the first 4 weeks after transplantation, and during all episodes of diarrhea. RESULTS Enteric pathogens were found in 60% of patients before or after transplantation. Pretransplantation screening revealed asymptomatic excretion of enteric pathogens in 29% (19/65). Forty-eight percent of patients undergoing BMT developed diarrhea. Diarrhea was mainly of noninfectious origin in the first 20 days after transplantation. More than 20 days after transplantation, the major causes of diarrhea were graft-versus-host disease and infection. Parasitic infections other than Cryptosporidium did not contribute significantly to morbidity in the pre- and posttransplantation period. Rotavirus and adenoviruses were found in approximately 12% and 5% of subjects, respectively. Bacterial infections in the posttransplantation period were found to be more common in India than in developed countries. Clostridium difficile-associated diarrhea was seen in the posttransplantation period but not before transplantation. Enterotoxigenic and enterohemorrhagic Escherichia coli caused symptomatic infections in the posttransplantation period, but the association of other classes of diarrheogenic E. coli with diarrhea was doubtful. CONCLUSIONS There was significantly higher mortality (P<0.01) in patients with symptomatic or asymptomatic gastrointestinal infections caused by bacteria than in patients with parasitic or viral infections or without enteric infections.