Protein S deficiency
Protein S deficiency is inherited in an autosomal (dominant/recessive) manner.
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A 43-year-old woman comes to the emergency department because of sudden-onset dyspnea. Her medical history is relevant for varicose veins in lower extremities, controlled diabetes mellitus, and 30 pack-year smoking history. The patient currently takes metformin and pioglitazone. Upon further questioning, the patient mentions that her sister died at 35 because of a pulmonary embolism. Physical exam shows clammy skin and diaphoresis, S3 gallop, erythema over varicose veins in her left leg. Her temperature is 37.8°C (100.04°F), pulse is 111/min, respirations are 18/min, blood pressure is 130/60 mmHg. She is heparinized to treat the suspected pulmonary embolism and started on a long-term prophylactic agent. Shortly after, the patient's clinical condition deteriorates (see image below).
Which of the following abnormalities is the most likely cause of these findings?