Thrombocythemia and Pulmonary Intra-Alveolar Coagulum in a Young Woman

A description is given of the clinical course and findings at autopsy in a 19-year-old girl with a myeloproliferative syndrome characterized primarily by thrombocythemia. This was associated with an unusual pulmonary disorder in which the alveoli were filled by a non-cellular exudate comprised of carbohydrate, fat and protein which resembled in some respects pneumonia attributed to Pneumocystis carinii. The possible interrelationship of the thrombocythemia and the intra-alveolar coagulum is discussed.