Pulmonary leukostasis: role of perfusion lung scan in diagnosis and follow up

A patient with hyperleukocytic myelomonocytic leukemia who presented to the emergency room with sudden pleuritic chest pain and dyspnea is reported. Clinical manifestations included dyspnea tachypnea and hyperventilation. Blood gas analysis revealed hypoxemia, hypocarbia, and respiratory alkalosis. Chest X ray was normal, and perfusion lung scan revealed a diffuse vascular occlusive pattern compatible with pulmonary leukostasis. The patient underwent immediate leukapheresis with subsequent mitigation of symptoms. A second perfusion lung scan showed evidence of significant improvement. To our knowledge this is the first published case of hyperleukocytosis presenting with pulmonary leukostasis that was successfully diagnosed and followed by serial perfusion lung scan.