Massive low-attenuation mediastinal, retroperitoneal, and pelvic lymphadenopathy on CT from lymphangioleiomyomatosis case report

Lymphangioleiomyomatosis (LAM) is a rare disease of women of child-bearing age characterized by the proliferation of smooth muscle throughout the lymph nodes and lymphatic channels of the retroperitoneum, mediastinum, and lungs. Most previous reports of LAM have concentrated on the pulmonary findings. Although mediastinal and retroperitoneal lymphadenopathy is known to be a prominent feature of the disease, it is rarely imaged. We present a case of a young woman with LAM who presented with massive pelvic, retroperitoneal, and mediastinal lymphadenopathy associated with a chylous pleural effusion on the left. On computed tomography (CT) the lymphadenopathy was heterogeneous in nature but was predominantly of low attenuation. We believe that when CT demonstrates low-attenuation lymphadenopathy in the mediastinum or retroperitoneum of a woman of child-bearing age, LAM should be considered as a likely diagnosis.