Melanosis coli
- Author:
Siang-Tong Kew
- Publication Type:Review
- Keywords:
melanosis coli, anthraquinone, lipofuscin, colorectal adenoma/carcinoma risk, complementary and alternative medicine.
- From:International e-Journal of Science, Medicine and Education
2012;6(supp1):S53-S60
- CountryMalaysia
- Language:English
-
Abstract:
Melanosis coli denotes brownish
discoloration of the colonic mucosa found on endoscopy
or histopathologic examination. The condition has
no specific symptom on its own. It is a fairly frequent
incidental finding of colonic biopsies and resection
specimens. The pigmentation is caused by apoptotic cells
which are ingested by macrophages and subsequently
transported into the lamina propria, where lysosomes
use them to produce lipofuscin pigment, not melanin
as the name suggests. Melanosis coli develops in over
70% of persons who use anthraquinone laxatives (eg
cascara sagrada, aloe, senna, rhubarb, and frangula),
often within 4 months of use. Long-term use is generally
believed to be necessary to cause melanosis coli.
The condition is widely regarded as benign and
reversible, and disappearance of the pigment generally
occurs within a year of stopping laxatives. Although
often due to prolonged use of anthraquinone, melanosis
can probably result from other factors or exposure to
other laxatives. It has been reported as a consequence
of longstanding inflammatory bowel disease. Some
investigators suggested that increase in apoptosis of
colonic mucosa by anthraquinone laxatives increased the
risk of colonic cancer. Recent data, including those from
large-scale retrospective, prospective and experimental
studies, did not show any increased cancer risk.
- Full text:W020150928568717633078.pdf
