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Clinical Images

A Colonic Effect of Over-The-Counter Supplements

Tokunbo Ajayi, MD, Mouen A Khashab, MD, and Vivek Kumbhari MD

September 30, 2017

A 71-year-old female underwent endoscopy to evaluate a 2-week history of melenic stool. She denied any other gastrointestinal symptoms. Her past medical history included heart failure with preserved ejection fraction, constipation, chronic kidney disease stage 3 and chronic back pain. She took oxycodone and ibuprofen for her back pain. She took the following over-the-counter supplements: cinnamon, cod liver oil, multi-vitamin, Boswellia, cranberry fruit concentration, liver detox (active ingredient: buckthorn) and colon helper (active ingredients: aloe and anthraquinones). She was up to date on age-appropriate cancer screening, including colonoscopy, which revealed atrophic gastritis and normal colonic mucosa. Her family history was negative for gastrointestinal cancer. She never used alcohol, tobacco or illicit drugs.

Her vital signs were within normal limits. Her exam was significant for a 3/6 systolic  ejection murmur at the upper right sternal border and pallor, and otherwise her exam was normal. Lab results were significant for hemoglobin of 9.6 g/dl, hematocrit of 30.2% (baseline hemoglobin and hematocrit was 13.1g/dl and 36.2%, respectively), iron 44 ug/dl, ferritin 81 ng/ml, iron saturation of 16% and TIBC of 270 ug/dl. Colonoscopy revealed an isolated 20 x 20 mm sessile polyp (Paris IIa)1 in the sigmoid colon with diffuse dark pigmentation (See Figure 1). 

She was started on omeprazole, ferrous gluconate and was advised to stop any non-steroidal anti-inflammatories. She did not require blood transfusion. On follow up, her melenic stool had resolved and her hemoglobin increased to 11.2 g/dl.



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2.Grilo I, Torres-Gómez J, Gómez-Regife L. Atypical melanosis coli resembling the appearance of cheetah skin. Endoscopy 2014;46 Suppl 1 UCTN:E437-8.

3. Kew ST, Chakravarthi S. Images in clinical medicine: melanosis coli. N Engl J Med 2013; 368: 2303

4. Freeman HJ. “Melanosis” in the small and large intestine. World J Gastroenterol 2008; 14: 4296-4299

5. Nusko G, et al., Melanosis coli-a harmless pigmentation or a precancerous condition? Zeitschrift Gatroenterology 1997; 35(5): 313-318.

Author Biography

Dr. Ajayi is a hospitalist at Johns Hopkins Medicine and Howard County General Hospital in Columbia, Maryland and research scientist at Johns Hopkins Gastroenterology Department. He was chief resident in the Department of Medicine at North Shore Medical Center Medical Center (NSMC) in Salem, Massachusetts. He attended medical school at the Obafemi Awolowo in Ile-Ife, Nigeria. 

Dr. Khashab is an expert in advanced and innovative endoscopic techniques, including ERCP, balloon-assisted enteroscopy, endoscopic mucosal resections, and interventional EUS. He also has clinical interests in removing large colon polyps and sphincter of Oddi dysfunction. Dr. Khashab’s research interests include natural orifice transluminal endoscopic surgery (NOTES).  He is an associate editor of the Fellows Corner section of Gastrointestinal Endoscopy. He has published more than 50 papers and book chapters, and is board certified in gastroenterology and internal medicine.

Dr. Vivek Kumbhari is Assistant Professor of Medicine and Director of Bariatric Endoscopy at Johns Hopkins Medicine. His areas of expertise include minimally invasive, non-surgical therapies to facilitate weight loss and the treatment of obesity related diseases such as hypertension and diabetes.