CASE 11

PATIENT: 60-year-old man

CHIEF COMPLAINT: This patient had traveled from London to Houston on a business trip. He had been instructed by his physician in London to consult a cardiologist in Houston to monitor his oral anticoagulant therapy.

MEDICAL HISTORY: The patient had a documented episode of deep vein thrombosis with pulmonary embolism 3 months before he made the trip. He had been hospitalized and treated with heparin and oral anticoagulants and was undergoing maintenance therapy with oral anticoagulant at the time of his visit to the United States.

FAMILY HISTORY: Noncontributory

DRUG HISTORY: The patient had been taking Coumadin (sodium warfarin) at a dosage of 5 mg per day.

PHYSICAL EXAMINATION: Noncontributory

LABORATORY RESULTS

A. London Results

	Patient	Normal
Prothrombin time	45 seconds	<18 seconds
aPTT	52 seconds	<50 seconds

B. Houston Results

Prothrombin time	20 seconds	8-11.5 seconds
aPTT	41 seconds	24-37.5 seconds

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