A female with classical paroxysmal nocturnal hemoglobinuria misdiagnosed as megaloblastic anemia

Abstract

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder of the hematopoietic stem cells, which manifests as bone marrow failure, hemolytic anemia, and thrombosis. PNH affects both sexes equally and may present at any age, although it is most often diagnosed in young adulthood. Here, we report a case of a middle-aged woman, presented with one and a half year history of anemia, significant fatigue, backache, and persistent high erythrocyte sedimentation rate. The patient has no organomegaly and did not give a history of thrombotic events previously. She was considered as a case of megaloblastic anemia at another center and treated accordingly. Her full blood count showed mild macrocytic anemia with slight polychromasia. The hemolytic anemia workup revealed slightly raised serum bilirubin (unconjugated) and undetectable haptoglobin with hemosiderin in urine. Ham's test was positive, and the diagnosis of PNH was confirmed by flow cytometry. The patient was treated with short-course steroids and folic acid, and her general condition has become stable.