MKSAP Quiz: dyspnea, chest tightness in an adolescent athlete
Scoring system predicts risk for hospital readmission
An 18-year-old male high school football player is evaluated for recurrent episodes of dyspnea, chest tightness and cough that have occurred during a game and limited his ability to participate. The symptoms resolve spontaneously in 20 to 30 minutes. The patient's father has known allergies but no known lung disease.
On physical examination, the patient is a healthy young man; the lungs are clear on auscultation. Office spirometry shows an FEV1 of 90% predicted and FEV1/FVC 80%.
Which of the following is the most appropriate next step in the evaluation of this patient?
A. Measure lung volumes and diffusion capacity
B. Perform an exercise challenge test
C. Perform allergy skin testing
D. Prescribe a physical conditioning program
MKSAP Answer and Critique
The correct answer is B) Perform an exercise challenge test. This item is available online to MKSAP 14 subscribers in the Pulmonology and Critical Care Medicine section, Item 57.
Exercise-induced asthma is a common manifestation of asthma. Nearly 90% of patients with asthma have exercise-induced asthma, provided adequate exercise intensity. Cold, dry air can enhance its occurrence. Exercise challenge (to >85% of maximal predicted heart rate) with post-exercise spirometry showing a 100% or greater reduction in FEV1 confirms the diagnosis of exercise-induced asthma. Exercise challenge test has a high specificity for the diagnosis when the reduction in FEV1 postexercise is 15% or greater. Airway obstruction after exercise peaks in 5 to 15 minutes and resolves in 20 to 30 minutes. Treatment with short-acting inhaled β-agonists 5 to 10 minutes before exercise prevents exercise-induced asthma in more than 80% of patients. With appropriate management, affected patients can engage in physical activity and do not need to limit or stop their involvement in sports. Lung volumes and diffusion capacity measurements are helpful in evaluating patients with suspected parenchymal lung diseases and are not likely to help in this patient. Although patients with parenchymal lung disease have dyspnea on exertion, their symptoms are typically progressive. Allergy skin test could be done in this patient at some point; positive results would not explain the patient's symptoms and would not be expected to change his management. Deconditioning manifests as dyspnea on exertion but is not typically associated with cough or chest tightness; therefore a physical conditioning program would be very helpful in this patient.
Key Point
- Exercise-induced asthma is confirmed by exercise challenge (to >85% of maximal predicted heart rate) with post-exercise spirometry showing a 20% fall in FEV1. Treatment with short-acting inhaled β-agonists 5 to 10 minutes before exercise prevents exercise-induced asthma in more than 80% of patients.