MKSAP Quiz
A 30-year-old woman is evaluated in the emergency department of a community hospital for a 2-week history of fatigue, malaise, low-grade fever and intermittent epistaxis. Her husband states that she has been forgetful and occasionally confused during this period. The remainder of the medical history is noncontributory.
On physical examination, there are bruises over the upper and lower extremities and palatal petechiae. Laboratory studies indicate a hemoglobin of 7.2 g/dL (72 g/L), leukocyte count of 9600/µL (9.6 × 109/L), platelet count of 12,000/µL (12 × 109/L), and serum lactate dehydrogenase concentration of 1700 U/L. The peripheral blood smear is shown.
Plasma exchange is unavailable at this hospital.
Which of the following is the most appropriate next step in management?
A. Observation
B. Prednisone
C. Random donor platelet transfusion
D. Plasma infusion
Answer and Critique
Correct Answer: D. Plasma infusion
This patient has at least four of the five manifestations that comprise the pentad of thrombotic thrombocytopenia purpura (TTP), including fever, neurologic abnormalities, thrombocytopenia, and microangiopathic hemolytic anemia (anemia, schistocytes, elevated serum lactate dehydrogenase concentration); the fifth manifestation of TTP is renal insufficiency. The treatment of choice for TTP is plasma exchange, which should be initiated as urgently as possible. However, because plasma exchange is not available at the admitting hospital, plasma infusion is the next best alternative and should be instituted immediately. Plasma infusion is effective for many patients with TTP, although in randomized studies, it has been shown to be less efficacious than plasma exchange. In this case, it should be considered a temporizing measure until transfer to a facility with plasma exchange is available.
The course of TTP is unpredictable and may be associated with catastrophic complications; therefore, observation alone is not an acceptable management approach.
The efficacy of prednisone in the therapy of TTP is controversial. Furthermore, it is not considered adequate as the sole therapy for TTP. Platelets may worsen the course of TTP and should be withheld in the absence of truly life-threatening bleeding.
Key Points
- Thrombotic thrombocytopenia purpura (TTP) is characterized by fever, neurologic abnormalities, thrombocytopenia, microangiopathic hemolytic anemia, and renal insufficiency.
- The treatment of choice for TTP is emergent plasma exchange, followed by plasma infusion when the former is not immediately available.
