Small Bowel Lymphangiomatosis Presenting With Amyloidosis: A Case Report.

Small bowel lymphangiomatosis is a rare benign lymphatic malformation with nonspecific clinical manifestations that may complicate preoperative diagnosis. We present the case of a 57-year-old male with a history of recurrent umbilical hernias who complained of abdominal pain, nausea, vomiting, and an unreducible ventral hernia, all of which suggested a small bowel obstruction. Imaging revealed a presumed strangulated hernia with bowel obstruction and abnormal thickening of various loops of small bowel. Exploratory laparotomy disclosed incarcerated and gangrenous small bowel requiring resection. Histopathologic evaluation demonstrated extensive small-bowel lymphangiomatosis with concurrent AA-dominant amyloidosis, confirmed by apple-green birefringence on polarized microscopy of a Congo red-stained sample. This case highlights a rare coexistence of lymphangiomatosis and amyloidosis and suggests a possible relationship between chronic inflammatory amyloid deposition and secondary lymphatic obstruction, which may contribute to lymphangioma formation.