Successful treatment of a patient with chyluria due to lymphangioleiomyomatosis using sirolimus

Abstract

Lymphangioleiomyomatosis (LAM) is a rare and progressive neoplastic disease of young woman, characterized by the proliferation of abnormal smooth muscle-like cells (LAM cells) in the lungs and axial lymphatics. A 44-year-old woman was referred to our hospital because pleural effusion was detected during a health checkup. She had chylothorax, chylous ascites, and chyluria, and her computed tomography scan showed a solid tumor in the pelvis. Surgical biopsy was performed; she was diagnosed as having LAM. We could not control the fluid collection and chyluria using standard medical treatments. Therefore, we chose to administer sirolimus, and her symptoms dramatically improved. The mechanism of chyluria presumably involved LAM cell infiltrates in the ureter via the lymphatic vessel flow, which causes LAM to develop because of ureter wall exposure.

Keywords: Chylothorax; Chylous ascites; Chyluria; Ezetimibe; Lymphangioleiomyomatosis; Sirolimus.

Fig. 1

Radiological findings on admission. Chest radiograph revealing right pleural effusion.

Fig. 2

Computed tomography (CT) scans (1.25-mm slice) on admission (A, B) and after 2 months of sirolimus treatment (C, D). A: Chest CT scan revealing moderate accumulation of the right pleural effusion and multiple thin-walled cysts (arrows) in both lung fields. B: Enhanced abdominal CT scan demonstrating ascites and a solid tumor (arrowheads) in the right pelvis. C: Chest CT scan revealing that the multiple small cysts in both lungs are stable and pleural effusion retention is decreased. D: Enhanced abdominal CT scan showing that the quantity of ascites fluid and size of the tumor lesion are smaller.

Fig. 3

Patient's clinical course.

Fig. 4

Photographs before and after treatment. A: Photograph of the chylous ascites. B: Photograph of chyluria. C: Photograph of the transparent urine.

Fig. 5

Results of the histopathological examination. A: The cell that had a kind of circular nucleus from a uniform circle in stained acidophilic cytoplasm forms a strand from a vacuole nest and multiplies (hematoxylin-eosin stain [HE], ×200). B: A part of the same type of cell became spindle-shaped and complex (HE, ×200). C–E: The immunohistochemical stain is positive for smooth muscle actin (C), HMB45 (D), and MelanA (E).