Duodenal Pseudomelanosis: A Literature Review

Abstract

Duodenal pseudomelanosis (also known as pseudomelanosis duodeni) is a rare endoscopic incidental finding defined by a pigmentation limited to the apex of the intestinal villi, which requires histological confirmation. While its exact pathogenesis is still poorly understood, it appears free from clinical consequences. This condition is believed to be associated with oral iron intake, antihypertensive drugs containing a sulfur moiety (i.e., hydralazine, furosemide), and several chronic diseases (i.e., hypertension, end-stage renal disease, diabetes). However, the exact prevalence of these treatments and comorbidities among patients with duodenal pseudomelanosis is not clearly defined. Several case reports and case series about duodenal pseudomelanosis have been published in recent years. In this review, we aimed to clearly define its endoscopic and microscopic presentation; its epidemiology, associated comorbidities, and drugs; the most useful special histochemical techniques used to classify the nature of the pigmentation; and the most relevant differential diagnoses. In addition, by considering our findings, we also formulated a number of hypotheses about its pathogenesis.

Esophageal Pseudomelanosis Causing Pseudoachalasia

“…This leads to proposed mechanisms involving iron and sulfur deposition in the mucosa secondary to either medication use or impeded clearance. 4 Esophageal pseudomelanosis is rare with only case reports in the literature and no clear etiology; it has never been described to cause strictures or pseudoachalasia. Further studies are needed to evaluate esophageal pseudomelanosis and its clinical significance.…”

Unusual endoscopic findings by capsule endoscopy: Duodenal and jejunal pseudomelanosis in patients with intake AT2 antagonists

“…The Three patients had Telmisartan Intake.The capsule endoscopy showed multiple diminutive black spots throughout the duodenum and jejunum. Histology showed multiple foci of a brown-black granular pigment inside macrophages within the tips of the villi 1 2 3 .…”

Pseudomelanosis Duodeni in a Child With Chronic Diarrhea

“…The characteristic histological finding shows pigment-laden macrophages in the lamina propria of duodenal villi. Additional findings include a positive histochemical stain for iron with Perl’s Prussian blue which stains ferric iron (Fe 3+ ), and Fontana-Masson, which stains ferrous iron (Fe 2+ ) (1). However, the biopsy specimen may be negative, given that the above stains may be unpredictable.…”