hem 3 - pacemaker

[ArchivalUser]

A 64-year-old man is evaluated in the emergency department for severe fatigue that has worsened over the past 3 months and recurrent epistaxis that has occurred over the past week.

He has not had fever or a recent illness, nor does he have any risk factors for HIV infection. He has not taken any over-the-counter medications nor used alcohol. His family history is significant for two siblings who died of cancer. On physical examination, petechiae are noted in the buccal mucosa and lower extremities. There is no lymphadenopathy or splenomegaly.

Laboratory studies on hospital admission indicate a normal activated partial thromboplastin time and prothrombin time, a hematocrit of 23%, leukocyte count of 1200/μL (1.2 x 109/L), neutrophil count of 300/μL (0.3 × 109/L), platelet count of 15,000/μL (15 × 109/L), and a reticulocyte count of 0.2% of erythrocytes. Serum chemistries, including lactate dehydrogenase, are normal. No significant red blood cell abnormalities are noted on peripheral blood smear. Chest radiograph is unremarkable. The bone marrow biopsy is shown (Figure 22).

The patient receives a transfusion with packed red blood cells and platelets.

Which of the following is the most appropriate treatment for this patient?

A Cytarabine and anthracycline chemotherapy
B Antithymocyte globulin and cyclosporine
C Allogeneic stem cell transplantation
D Plasma exchange

[ArchivalUser]

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[ArchivalUser]

C Allogeneic stem cell transplantation

[ArchivalUser]

B)
Key Point
Immunosuppressive therapy with antithymocyte globulin and cyclosporine is effective in reducing transfusion requirements in >70% of patients with aplastic anemia.

This patient has pancytopenia and hypocellular bone marrow consistent with a diagnosis of aplastic anemia. In half of patients with aplastic anemia, there is no obvious etiologic agent, such as a chemical, drug, or viral infection, to account for the development of the disease. Immunosuppressive therapy with antithymocyte globulin and cyclosporine has been shown to be effective in reducing transfusion requirements in more than 70% of patients with aplastic anemia and would be the preferred therapy in this patient.

Induction chemotherapy with cytarabine and anthracycline would be an appropriate therapeutic choice for patients with acute myeloid leukemia (AML). Although patients with AML commonly present with pancytopenia, their bone marrow is typically hypercellular, not hypocellular. Allogeneic stem cell transplantation can be curative in patients with aplastic anemia, but this patient's advanced age and lack of any living siblings make this option significantly less attractive than immunosuppressive therapy. Plasma exchange is not effective in patients with aplastic anemia because it is mediated by cellular immunity rather than by circulating autoantibodies.