Importance of pre-transplant colonoscopy in renal transplant recipients

Current recommendations for colorectal cancer screening for kidney transplant candidates are the same as for the general population. However, few studies have established the prevalence and characteristics of colorectal polyps in this population. The aim of this study is to describe the prevalence and characteristics of colonic lesions detected by pre-transplant colonoscopies in our kidney transplant population.

A retrospective study was conducted from January 2007 to December 2009 at the Centre Hospitalier de l'Universite de Montreal (Canada). Inclusion criteria are all renal transplant recipients with a test for colorectal cancer screening in the 5 years preceding the transplantation. Patients benefiting of a second transplantation were excluded. The files were reviewed for clinical data, including colonoscopy indication, endoscopic and pathologic results. Advanced lesions were defined as adenomas of 10 mm or greater or with a villous component. Polyps were considered proximal if they were at the level of or above the splenic angle.

This study includes 159 patients. A pre-transplant colonoscopy was performed in 40% (n = 64). Polyps were present in 32.8% (n = 21) of colonoscopies and 66.7% of them showed adenomas. Advanced lesions were present in 6.25% of the exams. Finally, 66.7% of patients with polyps had at least one proximal lesion.

The prevalence of colorectal polyps before transplant is high among renal transplant recipients. The high prevalence of proximal lesions supports the need for total colonoscopy.