Endometriosis is a common gynecological condition wherein there is an ectopic implantation of the uterine endometrial tissue. While several diagnostic modalities are described for the condition, laparoscopy remains the gold standard. There is still an undiscovered area to diagnose colonic endometriosis at an earlier stage. We present a case report of a reproductive age woman with cyclical rectal bleeding diagnosed with colonic endometriosis with colonoscopy and biopsy using saline injection lift and sampling technique. We in our report try to impress the fact that this differential should always be considered in the appropriate clinical setting, especially in women of childbearing age and in such cases, deeper tissue sampling techniques should be sought for, given better diagnostic yield. This may be clinically important given that it may aid in earlier diagnosis and thereby early initiation of appropriate therapy before the disease takes a complicated route. It may also be helpful in avoiding unnecessary surgery, along with the morbidity, complications and costs associated with same.
Keywords: Colonic endometriosis; Rectal bleeding.