Central airway obstruction due to cytomegalovirus-induced necrotizing tracheitis in a patient with AIDS. Cytomegalovirus (CMV) infection in patients with the acquired immunodeficiency syndrome (AIDS) can present as either disseminated disease, pneumonitis, retinitis, gastroenteritis, neuropathy, or a subclinical infection. We report a patient whose initial manifestation of CMV infection was severe central airways obstruction due to necrotizing tracheitis. At bronchoscopy, the lesion appeared deeply ulcerated, distinctly different from previously described airway lesions in patients with AIDS. Mucosal biopsies showed characteristic intranuclear and intracytoplasmic inclusions and cultures yielded only CMV. The patient responded partially to ganciclovir, steroids, and antibiotics against suspected anaerobic superinfection but died as a result of central nervous system disease believed due to toxoplasmosis or lymphoma. CMV infection of the upper airway should be considered in the patient with AIDS presenting with atypical cough or stridor and ulcerated endobronchial lesions. 