Pseudomelanosis duodeni (PD) is a rare dark speckled appearance of the duodenum 
associated with gastrointestinal bleeding, hypertension, chronic heart failure, 
chronic renal failure and consumption of different drugs. We report four cases 
of PD associated with chronic renal failure admitted to the gastroenterology 
outpatient unit due to epigastric pain, nausea, melena and progressive reduction 
of hemoglobin index. Gastroduodenal endoscopy revealed erosions in the esophagus 
and stomach, with no active bleeding at the moment. In addition, the duodenal 
mucosa presented marked signs of melanosis; later confirmed by histopathological 
study. Even though PD is usually regarded as a benign condition, its 
pathogenesis and clinical significance is yet to be defined.