Which of the following anemias is characterized by a defect in the CD55 and CD59 proteins on the surface of red blood cells?

A Hereditary spherocytosis
B Paroxysmal nocturnal hemoglobinuria ✓
C Sickle cell anemia
D Thalassemia major

Explanation

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired disorder characterized by a defect in the CD55 and CD59 proteins on the surface of red blood cells, making them more susceptible to complement-mediated lysis.

Source

ASH Education Program Book
Hematology Hematology: Anemia Hematology: Anemia Hard MEDICAL Confidence: high