CME questions: thrombocytopenia in adults.

1. A 35-year-old woman presents with incidental finding of thrombocytopenia (35,000/[micro]L) detected on a CBC done for a routine annual physical examination. She is entirely asymptomatic. Specifically, there is no history of thromboses or miscarriages. She takes no medications. Her sister has SLE and her mother has hypothyroidism. Blood counts are

otherwise normal. Review of peripheral blood smear confirms thrombocytopenia but shows no other abnormalities. Which of the following is the most appropriate initial management of this patient?

a. Platelet transfusion

b. Intravenous methylprednisolone 

c. Oral dexamethasone 

d. Close observation

2. A 45-year-old male with known HIV infection presents to the ER with altered mental status. He is afebrile and does not have meningeal signs. Initial laboratory testing reveals thrombocytopenia (28,000/[micro]L) hemoglobin 10.8g/dL, and normal WBC count. Creatinine is elevated at 2.2 mg/dL, LDH is approximately 5 times normal, bilirubin 1.9 mg/dL, and coagulation profile is normal. Review of peripheral blood smear reveals numerous schistocytes. Which of the following is most effective in the management of this condition?

a. Steroids

b. Platelet transfusion

c. Intravenous immunoglobulin infusion

d. Plasmapheresis 

3. A 56-year-old patient is admitted with acute MI. He undergoes coronary angioplasty and receives abciximab (Reopro[TM]) and heparin. He develops thrombocytopenia with platelet count dropping from 250,000[micro]L at admission to 50,000/[micro]L on 5th hospital day. He also develops unilateral leg swelling. Lower extremity Doppler study shows deep vein thrombosis. What is the most appropriate management after heparin is discontinued?

a. Start argatroban

b. Start warfarin

c. Check for heparin-PF4 antibodies and if positive change anticoagulation to argatroban

d. Start enoxaparin

4. In a patient with suspected heparin-induced thrombocytopenia, which of the following anticoagulants are clearly contraindicated?

a. Lepirudin

b. Argatroban

c. Enoxaparin

d. Fondaparinux

5. An 89-year-old male is admitted to ICU with fever, altered mental status, and hypotension. Blood cultures grow Gram-negative bacilli. On the second hospital day platelets drop from 160,000/[micro]L to 40,000/[micro]L and creatinine increases from 1.3 to 2.4 mg/dL. His PT is 22 seconds, INR 2.8, and PTT 55 seconds. He is noted to have melanotic stool. The most likely cause of thrombocytopenia is:

a. Heparin-induced thrombocytopenia

b. DIC

c. Liver dysfunction

d. TTP

6. A healthy 45-year-old male undergoing an insurance physical is noted to have a platelet count of 40,000/[micro]L, hemoglobin 16 grams/dL and WBC count 9000/[micro]L. He is asymptomatic and denies easy bruising or gingival bleed. Next step in management would be:

a. Check citrated blood count

b. Immunoglobulin infusion

c. Transfuse platelets

d. Corticosteroids

7. In which of the following cases is a bone marrow examination most likely to help in management?

a. A 32-year-old woman with SLE and platelet count of 80,000/[micro]L

b. A 41-year-old male with end-stage AIDS, altered mental status, renal dysfunction and platelet count of 60,000/[micro]Lr and schistocytes in peripheral blood

c. A 60-year-old with history of excessive alcohol use who presents with GI bleed and platelet count of 50,000/[micro]L

d. A 78-year-old male who presents with easy bruising. CBC reveals WBC 2100/[micro]L, hemoglobin 11 grams/dL, platelets 93,000/[micro]L

8. All of the following are true about thrombocytopenia following chemotherapy except:

a. Usually the nadir is 7 to 10 days after chemotherapy

b. Associated with anemia and leukopenia most of the time

c. Prophylactic platelet transfusion is recommended if platelet count is less than 30,000/[micro]L

d. Single donor platelets are preferred if transfusion is required

9. Thrombocytopenia is paradoxically associated with thrombosis in all of the following conditions except:

a. Antiphospholipid antibody syndrome 

b. Paroxysmal nocturnal hemoglobinuria 

c. Heparin-induced thrombocytopenia

d. Thrombocytopenia associated with GPIIb/IIIA antagonists

10. In which of the following cases is a platelet transfusion most clearly indicated?

a. A 26-year-old woman with easy bruising and normal CBC except for a platelet count of 40,000/[micro]L

b. A 60-year-old male with platelet count of 30,000/[micro]L the day after angioplasty for acute MI

c. A 70-year-old male with myelodysplastic syndrome who is admitted with melena and is noted to have platelet count of 60,000/[micro]L

d. A 46-year-old woman with SLE who is scheduled to undergo arthroscopy and is noted to have platelet count of 50,000/[micro]L

Answers to CME Questions

1. D, 2. D, 3. A, 4. C, 5. B, 6. A, 7. D, 8. C, 9. D, 10. C

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