Pulmonary fibrosis and sea-blue histiocyte infiltration in a patient with primary myelofibrosis.

The authors present the case of a 73 year old man with primary myelofibrosis, pulmonary fibrosis, and acquired sea-blue histiocytosis, who died of respiratory failure. Pathology of the lungs revealed infiltration by sea-blue histiocytes, and fibrosis in the alveolar septa, and clumps of these cells filling the alveolar spaces. Megakaryocytes were also occasionally observed in the alveolar capillaries.