Severe anemia owing to occult pulmonary hemorrhage: a diagnostic pitfall.

: The purpose of this paper is to increase the awareness about pulmonary hemorrhage as a possible cause of microcytic hypochromic anemia and to delineate diagnostic difficulties and possible pitfalls. An instructive case of anemia of unclear origin referred to our institution for a hematologic workup is presented. Microcytic hypochromic anemia owing to repeated occult alveolar hemorrhages was the only clinical sign of idiopathic pulmonary hemosiderosis in this case. The laboratory finding constellation in such cases may be misleading and may lead to misinterpretation. Awareness about this condition among pediatricians and hematologists can optimize and accelerate the diagnostic process.