Refractory 'Asthma' in a Teenage Athlete
A 14-year-old competitive soccer player presents with a 6-month history of exertional dyspnea, chest tightness, and a sensation of throat closing during sprinting. She denies wheeze and nocturnal symptoms. She uses albuterol 15–20 minutes before practice with minimal relief. Her primary care clinician started fluticasone/salmeterol 100/50 twice daily 3 months ago, but symptoms persist. Spirometry today: FEV1 98% predicted, FVC 102% predicted, FEV1/FVC 0.86; bronchodilator response negative. FeNO 18 ppb. Allergy skin prick tests negative. On exam, she has loud inspiratory stridor over the larynx that resolves with distraction. She is frustrated and has missed several games.
1. What is the most likely diagnosis, and what test would confirm it?
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Most likely diagnosis: inducible laryngeal obstruction (ILO), formerly vocal cord dysfunction. The history of inspiratory stridor localized over the larynx, symptoms triggered by sprinting and emotional stress, minimal relief with albuterol, and lack of nocturnal symptoms are classic. Asthma can coexist, but the absence of wheeze and the normal FeNO make isolated asthma less likely.
Confirmation: flexible laryngoscopy during a symptomatic episode (or during an exercise challenge that reproduces symptoms) showing paradoxical vocal fold adduction on inspiration. A normal examination between episodes does not exclude ILO. If laryngoscopy is unavailable, an exercise challenge with pre- and post-exercise spirometry can help exclude exercise-induced bronchoconstriction, but it does not confirm ILO.
2. How do you interpret the normal spirometry, negative bronchodilator response, and FeNO of 18 ppb?
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Normal spirometry does not rule out asthma, but it makes moderate-to-severe airflow obstruction unlikely at rest. A negative bronchodilator response and FeNO of 18 ppb (normal in children, generally below 20 ppb) lower the probability of eosinophilic airway inflammation. In this context, continuing to escalate asthma controller therapy is unlikely to help and may cause side effects. The findings support looking for an alternative explanation, especially ILO, while keeping in mind that mild asthma can have normal intervals. The key is the discordance between disabling symptoms and objective tests.
3. Outline your management plan, including what to stop, what to start, and how to coordinate care.
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Stop the fluticasone/salmeterol if there is no evidence of asthma; do not abruptly stop systemic steroids if recently started, but taper. Start referral to speech-language pathology for respiratory retraining and vocal hygiene; treat comorbid reflux or rhinitis if present; consider cognitive behavioral therapy for anxiety. Coordinate with the coach and school nurse to allow breathing techniques during practice and to avoid unnecessary rescue inhalers. Follow-up in 4–6 weeks; if symptoms persist, repeat laryngoscopy. Document the diagnosis to prevent future escalations.