You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is CD59 marker deficiency leads to which of the following disease? and explain in detail?
Ans. a. Paroxysmal nocturnal hemoglobinuria (PNH)Ref: Robbins and Cotran Pathologic Basis of Disease 9th Ed; Page No-642Paroxysmal Nocturnal HemoglobinuriaIncreases complement-mediated intravascular RBC lysis (impaired synthesis of GPI anchor for decay-accelerating factor that protects RBC membrane from complement).Acquired mutation in a hematopoietic stem cell.Increases incidence of acute leukemias.Patients may report red or pink urine (from hemoglobinuria).Associated with aplastic anemia.Triad: Coombs [?] hemolytic anemia, pancytopenia, and venous thrombosis.Labs: CD55/59 [?] RBCs on flow cytometry.PNH blood cells are deficient in three GPI-linked proteins that regulate complement activity:Decay accelerating factor, or CD55;Membrane inhibitor of reactive lysis, or CD59; andC8 binding protein.The most important is CD59, a potent inhibitor of C3 convertase that prevents the spontaneous activation of the alternative complement pathwayTreatment: Eculizumab (terminal complement inhibitor).