Fixed monophonic wheezing

Specialty: Respiratory.

• fixed localized wheeze
• persistent unilateral wheeze

Why it occurs

• Endobronchial bronchogenic carcinoma (tumor that partially obstructs the lumen of a segmental or lobar bronchus, generating a whistling sound with a single and constant tone located in a specific area of the chest, which is not modified by cough or bronchodilator treatment)
• Intrabronchial foreign body silently aspirated (usually in older adults with swallowing disorders or neurological sequelae)
• Post-tuberculosis or prolonged post-intubation scarring bronchial stenosis (localized narrowing of the airway)
• Bronchial adenoma or primary bronchial carcinoid tumor (benign neoplasm or low-grade endoluminal growth)
• Extrinsic compression of a bronchus due to a massive mediastinal adenopathy or vascular aneurysm.

Initial workup

Chest x-ray (may show indirect signs such as localized emphysema or atelectasis); Computed tomography (CT) of the chest with contrast and virtual reconstruction of the airway (mini bronchial prominence); Flexible bronchoscopy (test of absolute choice for direct visualization of the bronchial lumen, taking biopsies, brushing cytology or foreign body extraction).

Standard management

• Regular bronchodilator treatment with beta-2 agonists is not effective in resolving physical obstruction
• Methylprednisolone — 40 mg intravenously if there is associated peritumoral mucosal edema
• Definitive management requires endoscopic resection (laser, cryotherapy), placement of a bronchial prosthesis (stent) or surgical resection of the affected segment.