Infectious diarrhea in autologous stem cell transplantation: high prevalence of coccidia in a South American center

BACKGROUND: Diarrhea is frequently seen in autologous stem cell transplantation. Although toxicity related to conditioning is the most common cause, infectious pathogens can play a distinctive role particularly in certain regions and environments. METHODS: The role of enteropathogens was investigated in 47 patients submitted to autologous stem cell transplantation at a Brazilian center between May 2011 and May 2013. All patients who presented with diarrhea consented to stool sample analysis to identify the etiological agents including coccidia, Strongyloides sp., Clostridium difficile and other pathogenic bacteria. RESULTS: Thirty-nine patients (83%) had diarrhea, among whom seven (17.5%) presented with coccidia, three (7.5%) with Candida sp., one (2.5%) with C. difficile, and one (2.5%) with Giardia lamblia. There was a tendency toward a higher incidence of diarrhea in older patients (p-value = 0.09) and those who received conditioning with lomustine, etoposide, cytarabine, and melphalan (p-value = 0.083). Furthermore, the number of days of neutropenia was higher in patients with diarrhea (p-value = 0.06). CONCLUSIONS: The high frequency of diarrhea caused by coccidia shows the importance of investigating and correctly identifying etiological agents and highlights the possible varieties of intestinal infections in patients who undergo autologous stem cell transplantation.