Question

A 40-year-old woman presents to the emergency department for confusion and headache. She has a past medical history of seasonal allergies and hypothyroidism. Her pulse is 78 beats/minute, respiratory rate is 18 breaths/minute, blood pressure is 141/89 mm Hg, and the temperature is 101.1°F. Physical exam is remarkable for scattered petechiae. Laboratory findings include hemoglobin of 10 g/dL, platelet count of 25,000/microL, creatinine of 1.2 mg/dL, and normal fibrinogen. A peripheral blood smear is notable for multiple schistocytes. Which of the following is the most likely diagnosis?

a. Disseminated intravascular coagulation
b. Hemolytic uremic syndrome
c. Idiopathic thrombocytopenic purpura
d. Thrombotic thrombocytopenic purpura

Answer 1

The most likely diagnosis for the 40-year-old woman with confusion, headache, petechiae, and specific laboratory findings is Thrombotic Thrombocytopenic Purpura (TTP). Option d is the correct answer.

Step-by-step explanation:

The given clinical presentation of a 40-year-old woman with confusion, headache, fever, petechiae, and indications from blood tests such as a low hemoglobin level, a very low platelet count, increased creatinine, and multiple schistocytes on a blood smear strongly suggests a diagnosis of Thrombotic Thrombocytopenic Purpura (TTP). This condition is characterized by the classic pentad of symptoms: neurological symptoms (like confusion and headache represented in the case), fever, thrombocytopenia (low platelet count leading to petechiae), microangiopathic hemolytic anemia (indicated by schistocytes on the blood smear and low hemoglobin), and renal impairment (elevated creatinine). The normal fibrinogen level helps differentiate TTP from other similar conditions such as Disseminated Intravascular Coagulation (DIC) where fibrinogen levels are typically low due to consumption.