Prevalence of Endoscopic Colic Lesions among Patient Awaiting Kidney Transplantation

Abstract

Introduction: Current recommendations for colorectal cancer screening in kidney transplant candidates are the same as those that apply to the general population. However, end-stage renal disease is associated with an increased risk for several types of cancer. A number of studies have shown an increased risk of colorectal cancer in this population, while other more powerful studies have shown a non-significant risk. Few studies however have yet established the prevalence and characteristics of colic lesions (polyps) in this population. Methods: Retrospective study of all patients transplanted from January 2007 to December 2009 at Centre Hospitalier Universitaire de Montréal (QC, Canada). Patients transplanted for a second time were excluded from the study. Data regarding demographics, lifestyle, comorbidities, primary renal disease characteristics were collected. For every colonoscopy performed in the 5 years preceding transplantation, the indication, endoscopic and pathologic results were also obtained. Results: 159 patients were included. A pre-transplant colonoscopy was performed in 40% of patients (n=64). Patients who underwent colonoscopies were significantly older (55.6 ± 8.7 vs 43.1 ± 12.1 yrs; p< 0.05), had a higher BMI (28.3 ± 5.3 vs 24.9 ± 5.3 kg/m2; p< 0.05), a greater prevalence of diabetes (30 vs 6% p< 0.05), dyslipidemia (61 vs 41%; p< 0.05) and diabetic nephropathy (23 vs 6%; p< 0.05). Among patients who underwent colonoscopies, polyps were present in 32.8% (n=21), 19% of which had large polyps (>10mm) and 62% of which had proximal polyps (above the splenic flexure). Histologically, among patients with polyps, 66.7 % had adenomas. Nineteen patients were younger than 50 years old at the time of colonoscopy. Five of them had polyps (26.3%). No significant differences were noted between the groups with and without adenomas. Moreover, there were no significant differences in the prevalence of polyps between the groups with and without diabetic nephropathy or metabolic syndrome's criteria. Conclusion: Polyp prevalence is high among renal transplant candidates. The high frequency of patients with proximal lesions justifies the performance of a total colonoscopy. Our results emphasize the indication of a screening colonoscopy among the renal transplant candidates.