Question

A 62-year-old man presents with shortness of breath, some chest discomfort, and palpitations. Upon examination, his pulse rate is 200/ min; blood pressure is 100/75 mm Hg, and he has an oral temperature of 98.7°F. A 12-lead ECG examination reveals the wave patterns in the figure below. He has a history of chronic bronchiolitis. He has been taking drugs to control his condition for the last 6 months, since he quit smoking.

What is the most likely cause of these symptoms?

1. Treatment with inhaled corticosteroids
2. Treatment with oral steroids
3. Treatment with a phosphodiesterase-4-inhibitor
4. Treatment with theophylline
5. Treatment with antibiotics

Answer 1

The 62-year-old man's symptoms are most likely caused by treatment with theophylline, a medication known for its narrow therapeutic window and potential to cause cardiovascular side effects.

Step-by-step explanation:

The most likely cause of the 62-year-old man's symptoms, which include shortness of breath, chest discomfort, and palpitations with a high pulse rate of 200/min, is treatment with theophylline. Theophylline is a bronchodilator often used to treat lung conditions such as chronic bronchiolitis. However, it has a narrow therapeutic window and can cause side effects that may lead to these symptoms if levels in the blood are too high.

Given the man's history of chronic bronchiolitis and the description of his symptoms and vital signs, theophylline toxicity is a likely differential diagnosis. The other listed medications, such as inhaled corticosteroids, oral steroids, phosphodiesterase-4-inhibitors, and antibiotics, are less likely to cause such acute cardiovascular effects. Close monitoring and possibly theophylline serum level measurement would help confirm the diagnosis and manage the patient's condition.