Intraperitoneal India ink deposits appearing as endometriosis in a patient with chronic pelvic pain

Visualization and biopsy of suspicious peritoneum can confirm endometriosis. Endoscopic India ink tattooing can lead to peritoneum that visually mimics endometriosis.A woman with chronic pelvic pain and a history of treated endometriosis underwent diagnostic laparoscopy. Previously, a small bowel endoscopy had been performed to evaluate the pain. At laparoscopy, black peritoneal lesions were seen and biopsied due to concern for endometriosis. Pathology concluded the lesions to be carbon-based ink. Investigation revealed that tattoos placed during the small bowel endoscopy used India ink.Endoscopic India ink tattooing used to demarcate an area of bowel for later identification can stain peritoneal surfaces and mimic endometriotic implants.