Kaposiform lymphangiomatosis, a newly characterized vascular anomaly presenting with hemoptysis in an adult woman.

Disorders of the pulmonary lymphatic system include macro- and microcystic lymphatic malformations, primary or secondary lymphangiectasias, generalized lymphatic anomalies, diffuse pulmonary lymphangiomatosis, and combinations of lymphatic and other tissue anomalies, including lymphangioleiomyomatosis (LAM). We report a case of a patient with a newly defined entity classified as kaposiform lymphangiomatosis (KLA). This 50-year-old nonsmoking Hispanic woman presented with a 20-year history of cough, hemoptysis, chyloptysis, and pleuritic chest pain. Laboratory evaluation demonstrated a low normal platelet count, elevated d-Dimer, low normal fibrinogen, and elevated fibrin split products. Chest computerized tomography imaging showed enlarged hypodense lymph nodes in the mediastinum and hila, and peribronchovascular thickening, without evidence of cystic parenchymal lesions. Magnetic resonance imaging of the chest showed cystic mediastinal lymph nodes with heterogeneously increased T2 and decreased T1 signal intensity. Fiberoptic bronchoscopy revealed hyperemic mucosa with granular appearance suggestive of a submucosal infiltrative process. Pathological specimens revealed dilated, malformed lymphatic channels within the pleura, pulmonary septa, and bronchovascular bundles, and foci of perilymphatic and intralymphatic spindle cells which reacted with the Prospero homeobox protein 1 (PROX-1) immunostain. The morphology and immunohistochemistry results were consistent with a diagnosis of KLA. This newly recognized clinical-pathological entity among intrathoracic lymphatic anomalies is distinguished from generalized lymphatic anomaly and diffuse pulmonary lymphangiomatosis in part by characteristic hematological abnormalities and hemorrhagic complications, including hemoptysis, as experienced by our patient.