Treatment of a nephrotic syndrome by endoscopic removal of a villous adenoma of the duodenum.

Summary We report the case of a patient diagnosed with a villous adenoma of the duodenum showing high degree dysplasia who developed a nephrotic syndrome (NS) due to a membranous nephropathy (MN), demonstrated by renal biopsy. Only the endoscopic resection of the duodenal adenoma could control the NS. The first manifestation of a MN is often the development of a NS. Up to 20% of patients older than 65 years who develop a MN have cancer. Tumours most often identified are those of lung, prostate and digestive tract. A renal biopsy is required to identify this type of nephropathy. If a diagnosis of MN is made, an associated tumour should be looked for.