Microsporidia infection in transplant patients

Background Microsporidia are the most common cause of chronic diarrhea in p atients infected with human immunodeficiency virus. Patients who have under gone organ transplantation may also be infected. The precise immune defect and the clinical picture in transplant patients have not been studied. Methods. We report a case of microsporidia infection in a heart transplant patient and review three other cases reported in the literature. Results. Infection in three solid organ transplant patients occurred when t he patients were receiving immunosuppressive therapy for rejection 1.5-3 ye ars after transplantation. Patients had chronic diarrhea, vomiting, dyspeps ia, and weight loss for 1 month to 3 years. Conclusions. Microsporidia may be the cause of chronic unexplained diarrhea and gastrointestinal disturbances in transplant patients. Defects in cell- mediated immunity probably play a role in maintaining the chronicity of thi s infection. Specific screening requests should be made to the microbiology laboratory when microsporidia infection is suspected.