Melanosis coli is a brown to black discoloration of the colon mucosa usually associated with long-term ingestion of laxatives. However, melanosis coli can be found in patients with no history of laxative use. Regular use of herbal remedies could be the major source of anthranoid laxatives in such patients. We designed a prospective case series study to identify the clinical characteristics and etiology of melanosis coli in affected patients. This study took place in Ankara, Turkey, between 08/2005 and 11/2006. Patients with endoscopic diagnosis of melanosis coli were interviewed for demographical data and use of herbal remedies. A total of 380 colonoscopies were performed during this period. Melanosis coli was diagnosed endoscopically in 12 patients (3.17%), 11 of whom were found to have characteristic pigment-laden macrophages in histopathological examination. Herbal remedies were the main etiological factor in the development of melanosis coli in 10 out of 11 patients. Diffuse involvement was found in 2 patients who had a history of long-term use. In 8 patients, melanosis coli was located in the left side of the colon. Although melanosis coli is a harmless discoloration of colonic mucosa resulting from complementary or alternative medicine, we believe that this association with herbals was overlooked or not inquired in patients. Therefore, it should be emphasized that “natural” or “alternative” is not equal to “safe”.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
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