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2 February 2012 - Case #231

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Thanks to Dr. Jamie Shutter, East Carolina University Brody School of Medicine, for contributing this case.

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Case #231

Clinical history:
94 year old woman with GI bleed presents for upper and lower endoscopy. Endoscopist notes spotty hyperpigmentation throughout duodenum without other associated abnormalities.

Microscopic images:

What is your diagnosis?

Click here for diagnosis and discussion:

Diagnosis: Melanosis duodeni

Melanosis duodeni, also known as pseudomelanosis duodeni, is due to brown-black pigment in macrophages in the lamina propria of the proximal duodenum. It is often but not always identified at endoscopy. It is due to iron or sulfur and may be associated with oral iron intake, hypertension, diabetes or end stage renal disease (J Formos Med Assoc 1995;94:632, Endoscopy 2008;40:165). It is not associated with laxative abuse (J Clin Gastroenterol 1988;10:127). It is also not associated with lipofuscin pigment, which is identified in melanosis coli.

Melanosis duodeni has no known clinical significance.

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