Pseudomelanosis Duodeni and Duodenal Polyp

A Rare Case of Duodenal Pseudomelanosis

A black-spotted duodenal mucosa was observed during endoscopy of a man with several comorbidities including hypertension and end-stage kidney disease. Histopathological examination revealed pigment-laden macrophages in the lamina propria of the duodenal villi, which was consistent with duodenal pseudomelanosis.

Duodenal Pseudomelanosis: A Literature Review

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.

Iron pill-induced duodenitis: A distinct pattern of duodenal mucosal injury in a patient with a duodenal mass

Ferrous sulfate is an oral iron supplement commonly used to treat iron deficiency anemia. Upper gastrointestinal (GI) tract mucosal damage with associated tissue iron accumulation can sometimes occur with therapeutic dosages of oral iron-containing medications. A distinct histologic pattern of iron deposition with associated inflammatory and reactive changes caused by mucosal injury from oral iron-containing medications has been most commonly described within gastric biopsies and has been referred to as "iron-pill gastritis". There have only been very rare reports of duodenal mucosa biopsies demonstrating predominantly extracellular crystalline iron deposits with surrounding tissue inflammation and injury analogous to the "iron-pill gastritis" pattern. Here we report a case of "iron pill-induced duodenitis", an uncommon histologic pattern of duodenal iron deposition and mucosal injury seen in a female in her 50 s with clinical findings of a duodenal mass.