A Case Of Paroxysmal Nocturnal Hemoglobinuria In A Patient With Myelodysplasia

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired hematological disease of the hematopoietic stem cell. PNH arises as a consequence of non-malignant clonal expansion of hematopoietic stem cells and progeny mature blood cells of both myeloid and monocyte lineage, which are deficient in some surface proteins, including the two complement regulators CD55 and CD59. As a result, PNH erythrocytes are incapable to modulate on their surface physiologic complement activation, leading to complement-mediated intravascular hemolysis, which is the central clinical feature of PNH. We present a case of a 16 years old Ukrainian boy who presented with a diagnosis of myelodysplastic syndrome and who was found to be affected by PNH.