Pseudomembranous Tracheobronchitis With Severe Tracheal Stenosis and Masked Bronchial Obstruction

BackgroundPseudomembranous tracheobronchitis (PMTB) is a rare condition characterized by the formation of endobronchial pseudomembranes. PMTB overlaps with necrotizing tracheobronchitis or plastic bronchitis. The reported infectious etiology mainly includes invasive aspergillosis. PMTB can cause serious airway obstruction; however, urgent tracheotomy is rarely required.Case ReportA 46-year-old woman was transferred to the emergency department (ED) with a 1-week history of progressive dyspnea and cough that was preceded by fever and sore throat. She was previously healthy except for a 20-year history of mild palmoplantar pustulosis. Stridor was evident. Nasolaryngoscopy performed in the ED revealed severe tracheal stenosis caused primarily by mucosal edema and secondarily by pseudomembranes. Initially, tracheitis was considered the sole cause of dyspnea. Although she underwent urgent tracheotomy to prevent asphyxia, her respiration deteriorated progressively. Bronchoscopy revealed massive pseudomembranes obstructing the bilateral bronchi, which led to the clinical diagnosis of PMTB. Subsequent toilet bronchoscopy markedly improved her ventilation. The causative pathogen was not identified despite extensive work-up, including molecular biological testing. Histopathologic examination of the pseudomembranes revealed fibrin with abundant neutrophils, which was consistent with PMTB. Associated conditions, including immunodeficiency, were not found. Her condition improved with antibiotics and repeated toilet bronchoscopy.Why Should an Emergency Physicians Be Aware of This?PMTB is an important differential diagnosis of airway emergencies. PMTB can present with critical edematous tracheal stenosis and masked bronchial pseudomembranous obstruction. Emergency physicians should include PMTB in the differential diagnosis in adult patients with acute central airway obstruction because it requires prompt multimodal treatment.