Paroxysmal nocturnal haemoglobinuria - a rare entity in pancytopenia: a case report

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired hematologic disorder characterized by hemolysis, bone marrow failure, and thrombosis. This case report details a 22-year-old male diagnosed with subclinical PNH, who presented with symptoms of fatigue and dyspnea on exertion. The classical symptoms of hemoglobinuria were not seen in our patient. Laboratory evaluation revealed pancytopenia, macrocytosis and low reticulocyte count. Serum B12 levels and iron studies were normal. Flow cytometry identified deficient expression of glycosylphosphatidylinositol (GPI)-anchored proteins on the patient’s erythrocytes, confirming the diagnosis of PNH. As our patient was in the subclinical stage, he responded to conservative therapy. Avoidance of stressors lead to significant clinical improvement. This case highlights the importance of considering PNH in young adults with unexplained pancytopenia, hemolysis, hematuria or venous thrombosis and provides insights into the management of this challenging condition. Financial constraints to the use of eculizumab in PNH, in developing countries like India, may present as a therapeutic challenge. However, response to bone marrow transplantation underscores its efficacy in controlling hemolysis and improving quality of life in PNH patients who develop aplastic anemia.