IntroductionColorectal disease is common throughout the world, but the spectrum of diagnoses across Africa remains largely unexplored. There is anecdotal evidence of changing colorectal disease but this has not been systematically investigated. The aim of this study was to enhance our insight into the spectrum of colonoscopic diagnoses in Zambia.MethodsWe retrieved written colonoscopy reports from January 2008 to December 2015. Collected data were coded by experienced endoscopists and analysed by age, sex, referral source, indication and diagnosis. ResultsIncluded in this analysis were 573 colonoscopy reports. The most common diagnosis was haemorrhoids (n=151, 26%), followed by tumours (n=96,17%). Over this time period, the proportion of normal colonoscopies decreased by 32% (P<0.001), presumably due to introduction of screening of all requests, while the rate of polyp detection increased from 5% to 10% (P=0.006). The detection of polyps was highest in patients less than 16 years (OR 8.4; 95% CI 2.4-26.2, P<0.001). Of those with colorectal tumours, 33/96 (35%) were less than 45 years although the occurrence was higher with advancing age (P=0.02). Diverticular disease was more common in older age groups (median (IQR) age 70 (60-75) years, versus 47 (34-62) years for those without the disease; P=0.0001).ConclusionThis audit has shown that more than a third of colorectal tumours seen during colonoscopy are in patients below the age of 45 years, with the occurrence of polyps being highest in those below 16 years. Diverticular disease is most common in older age groups