Intraoperative discovery of melanosis coli during emergent bowel resection for perforation

Abstract

A patient was taken to the operating room with a presumptive diagnosis of necrotic small bowel and colon. During the procedure, it was noted that she had black mucosa throughout the colon. Several factors suggested viable colonic tissue, and the decision was made to not resect the colon as originally planned. Final pathology of the specimen would later reveal melanosis coli, an ultimately benign diagnosis. Further questioning of the patient found that she had taken a herbal laxative supplement containing several components which are known to cause melanosis coli. We hope that this case report will serve as a reminder to surgeons and clinicians to remember melanosis coli as a clinical entity when confronted with blackened or darkened colonic mucosa. On review of available literature, we identified other cases in which melanosis coli was discovered intraoperatively, and we propose a number of factors to support intraoperative decision making.

Keywords: Drugs: gastrointestinal system; Gastrointestinal surgery; General surgery; Unwanted effects / adverse reactions.

Figure 1

Characteristic mucosal pattern of melanosis coli on stretch of the mucosa.

Figure 3

Initial right colon specimen with mucosal discolouration.

Figure 2

CT images demonstrating fluid collections in lower abdomen/pelvis (red arrow).

Figure 4

Extra segment of transverse colon with mucosal discolouration.

Figure 5

Mucous fistula with dark mucosa.