Endoscopic Diagnosis of Primary Intestinal Lymphangiectasia in an Adult With Refractory Protein-Losing Enteropathy: A Case Report.

Primary intestinal lymphangiectasia (PIL) is a rare disorder characterized by dilated lymphatic vessels in the gastrointestinal tract, leading to protein-losing enteropathy (PLE). We report the case of a 43-year-old male presenting with refractory PLE, characterized by generalized edema, chronic diarrhea, and significant weight loss over four months. Despite multiple consultations and treatments for presumed inflammatory bowel disease, his symptoms persisted, and his condition worsened. An upper endoscopy was performed, revealing white villi in the duodenum. Histopathological examination of duodenal biopsies confirmed the presence of markedly dilated lymphatic vessels in the lamina propria, consistent with PIL. The patient was managed with a high-protein, low-fat diet supplemented with medium-chain triglycerides (MCTs) and octreotide therapy. This treatment regimen led to significant clinical improvement, including reduced edema, normalization of albumin levels, and resolution of gastrointestinal symptoms. This case underscores the importance of considering PIL in adults with refractory PLE.