Case Report
A 55-year-old male with history of coronary artery disease, chronic kidney disease stage 4, diabetes mellitus, uncontrolled hypertension (on multiple antihypertensive medications), and iron deficiency anemia was referred for esophagogastroduodenoscopy (EGD) for evaluation of intractable nausea and vomiting. EGD showed black speckled pigmentation of the duodenal mucosa (Figure 1). Duodenal biopsy revealed hemosiderin deposition in the lamina propria of the duodenum, consistent with a diagnosis of pseudomelanosis duodeni (PMD; Figure 2).
Figure 1.

Black speckled pigmentation of the duodenal mucosa shown on EGD.
Figure 2.

Lamina propria slide showing plasma cells, lymphocytes, and pigmented macrophages consistent with pseudomelanosis duodeni.
PMD is the rare endoscopic appearance of black speckled pigmentation of the duodenum commonly seen in females in the sixth and seventh decades of life.1,2 The most common extracolonic site for pseudomelanosis of the gastrointestinal tract is the duodenum.3 While melanosis coli is secondary to accumulation of lipofuscin in the macrophages of the lamina propria, the predominant pigments deposited in PMD are iron sulfide and hemosiderin (Figure 3).3,4 Contrary to association of melanosis coli with anthraquinone laxatives, PMD has no such reported links. PMD has been associated with several medical conditions, including end-stage renal disease, hypertension, chronic heart failure, diabetes mellitus, gastrointestinal hemorrhage, and medications including anti-hypertensives and iron supplementation.1,2
Figure 3.

Blue pigmentation on iron Prussian stain of pseudomelanosis duodeni confirming that the pigment is iron.
Disclosures
Author contributions: A. Sathyamurthy wrote the manuscript and provided the endoscopy images. H. Chela and Z. Arif reviewed the literature and wrote the manuscript. Z. Arif provided the endoscopy images. J. Holly provided the histopathology images. M. Arif supervised manuscript creation and is the article guarantor.
Financial disclosure: None to report.
Informed consent was obtained for this case report.
References
- 1.Magalhães Costa MH, Fernandes Pegado M, Vargas C, et al. Pseudomelanosis duodeni associated with chronic renal failure. World J Gastroenterol. 2012;18(12):1414–1416. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2.Kuo YC, Wu CS. Duodenal melanosis. J Clin Gastroenterol. 1988;10(2):160–164. [DOI] [PubMed] [Google Scholar]
- 3.Almeida N, Figueiredo P, Lopes S, et al. Small bowel pseudomelanosis and oral iron therapy. Dig Endosc. 2009;21(2):128–130. [DOI] [PubMed] [Google Scholar]
- 4.Yamase H, Norris M, Gillies C. Pseudomelanosis duodeni: A clinico-pathologic entity. Gastrointest Endosc. 1985;31(2):83–86. [DOI] [PubMed] [Google Scholar]
