Introduction
Both primary care and subspecialty physicians are frequently called upon to evaluate patients with shortness of breath. This dyspnea may be labeled "difficult or refractory asthma." In some cases, the site of origin of this dyspnea may in fact not be the bronchial airways or the lung parenchyma, but rather the larynx.
Most of us are familiar with the clinical management of shortness of breath due to asthma or chronic obstructive pulmonary disease; however, a high index of suspicion is needed to carefully unravel a patient's symptom complex and pinpoint a diagnosis of pathology in the larynx. The diagnosis of laryngeal causes of dyspnea may escape accurate diagnosis for years, and may result in inappropriate and dangerous long-term treatment, including use of chronic maintenance corticosteroids. This may result in needless diagnostic tests, potentially invasive therapeutic interventions, and possible debilitating long-term side effects from inappropriate treatment.
Patients with dyspnea originating in their larynx may complain of shortness of breath, which may be accompanied by a wheezing or stridorous sound. Others may state that their symptoms are worsened by physical exertion. The recognition of the laryngeal origin of these syndromes may lead to a more timely diagnosis.
The highest yield diagnostic study in the majority of laryngeal disorders is the direct visualization of the larynx at the time a patient is experiencing symptoms. Careful examination with a flexible or rigid laryngoscope, or indirect visualization of the larynx with the laryngeal mirror, is needed to establish an appropriate or an accurate diagnosis. If appropriate examination cannot be done, or the diagnosis is in question, prompt referral to a competent otolaryngologist is necessary. In specialized centers, problems with the vocal cords and speech production may be further evaluated with specialized diagnostic equipment, such as a laryngostroboscope. This discussion will center around the laryngeal disorders that may lead to dyspnea, and disorders of voice will not be covered with this summary.