Membranous tracheitis is an acute exudative bacterial infection (S aureus, H influenzae, M catarrhalis, streptococci, and pneumococci) of the upper airway capable of causing life-threatening airway obstruction. It may present as a primary infection or occur as a secondary bacterial complication of a viral infection of the upper respiratory tract. This locally invasive infection of the tracheal mucosa below the vocal cords produces copious purulent secretions. The exudate can form a thick plug that may ultimately lead to an acute tracheal obstruction. Patients appear toxic, with high fever and a croup-like syndrome that can progress rapidly. The characteristic “membranes” may be seen on x-rays of the airway as edema with an irregular border of the subglottic tracheal mucosa. On direct laryngoscopy, profuse purulent secretions can be found in the presence of a normal epiglottis. The differential diagnosis includes acute laryngotracheobronchitis, RPA, epiglottitis, peritonsillar abscess, foreign-body aspiration, and acute diphtheric laryngitis.
Management and Disposition
Otolaryngologic consultation should be obtained as soon as the diagnosis is considered. Direct visualization of the trachea is more important than pursuing a radiologic diagnosis. Aggressive airway management, including endotracheal intubation, may be needed to protect the airway and allow for repeated suctioning to prevent acute airway obstruction. The patient should be admitted to the intensive care unit for close monitoring. Parenteral antibiotic coverage against suspected organisms (S aureus, S pneumoniae, group A Streptococcus (S pyogenes), α-hemolytic streptococci, H influenzae strains, and M catarrhalis) should be instituted immediately.
Bacterial tracheitis often presents with acute, severe airway obstruction after a short prodrome. It should be suspected in all patients with an atypical croup-like presentation: unusual age group, toxic appearance, not improving with routine croup therapy, and unusual appearance of the tracheal lumen on plain radiographs.
In bacterial tracheitis, up to 50% of soft-tissue films may delineate a subglottic membrane.
Membranous Tracheitis. Lateral soft-tissue x-ray of the neck in a 13-year-old girl with the acute onset of stridor after 3 days of sore throat. Membranes (arrows) are visible in the subglottic region. (Photo contributor: Matthew R. Mittiga, MD.)