Utility of colonoscopy in the evaluation of diarrhea in solid organ transplant recipients.

Background: Diarrhea is common in solid organ transplant recipients. Colonoscopy with random biopsies is performed frequently in the diagnostic evaluation of the posttransplant population with diarrhea. The purpose of this study was to determine the sensitivity of colonoscopy with random biopsy in determining a specific diagnosis and changing management in solid organ transplant recipients with diarrhea.

Methods: From October 1996 to June 2008, 88 patients were identified who had undergone solid organ transplantation and subsequently underwent colonoscopy for an indication of "diarrhea." These patient's electronic medical records were reviewed to determine patient demographics, laboratory results, findings on colonoscopy and histopathology, and any subsequent diagnoses made and management changes in relation to the diarrhea.

Results: Eighty-eight patients (mean age 54 years, 65% male) underwent colonoscopy a mean of 69 months after transplantation. Abnormal colonoscopic findings were seen in 16 (18.2%) patients. Histopathology was abnormal in 17/80 (21.3%). However, only eight (9.1%) had findings on colonoscopy or pathologic condition that led to specific diagnosis being made. In addition, only nine (10.2%) patients had a change in medical management as a direct result of colonoscopy with biopsy.

Conclusion: Although colonoscopic or histopathologic abnormalities are common in the solid organ transplant recipient with diarrhea, the findings rarely lead to a specific diagnosis or management change. Colonoscopy with biopsy should be performed only after noninvasive testing for infectious diarrhea and a thorough review and adjustment of medications. In many patients, a trial of antidiarrheal medication is warranted before colonoscopy.