A 34-year-old man comes to the office due to severe fatigue. The patient was diagnosed with paroxysmal nocturnal hemoglobinuria 3 years ago, and he has required several blood transfusions due to anemia. Treatment is initiated with a monoclonal antibody that prevents formation of the protein complex leading to hemolysis in this patient. Prophylactic pharmacotherapy will be required to prevent infection by which of the following organisms?

Question

A 34-year-old man comes to the office due to severe fatigue.  The patient was diagnosed with paroxysmal nocturnal hemoglobinuria 3 years ago, and he has required several blood transfusions due to anemia.  Treatment is initiated with a monoclonal antibody that prevents formation of the protein complex leading to hemolysis in this patient.  Prophylactic pharmacotherapy will be required to prevent infection by which of the following organisms?

Quizplus · Accepted Answer

Eductional Objective: Paroxysmal nocturnal hemoglobinuria leads to the formation of membrane attack complexes on erythrocytes.  Treatment with monoclonal antibody against C5, the first component of the membrane attack complex, can improve symptoms.  However, it also increases risk for encapsulated bacterial infection.  Therefore, patients require vaccination and antibiotic prophylaxis against Neisseria meningitidis and Streptococcus pneumoniae.

A 34-Year-Old Man Comes to the Office Due to Severe