A rare probably autoimmune process which results in widespread hemosiderin deposition in the lungs. The disorder is seen most commonly in children under the age of 10 years and affects males and females equally. In adults, males are affected more than females and the disease is usually less severe than in children.
Prognosis is poor with recurrent episodes and remissions.
Patients generally die within 5 years due to cor pulmonale. Following acute hemorrhage there are patchy parenchymal infiltrates with a perihilar and lower lung predominance that may resemble a pneumonia. Bilateral, hazy parahilar opacities can be seen and may mimic pulmonary edema. The infiltrates typically clear over 5 to 7 days. A reticulonodular interstitial pattern develops as blood is cleared from the alveoli and hemosiderin is deposited within the septa.