Abstract
BACKGROUND: Tracheobronchomegaly, also known as Mounier-Kuhn syndrome (MKS), is a rare congenital condition characterized by significant dilation of the trachea and main bronchi along with an abnormal wall structure. Diagnosis can be confirmed through computed tomography, pulmonary function tests, and diagnostic bronchoscopy. Currently, there is no curative treatment for MKS; thus, symptomatic and supportive care remain the primary therapeutic approaches. Early diagnosis, effective infection control, and individualized management are crucial for improving patient outcomes. METHODS: This case report describes a middle-aged woman who presented with chronic cough, expectoration, and wheezing. She had been misdiagnosed with chronic obstructive pulmonary disease (COPD) at a local hospital for an extended period and was subsequently referred to our institution for fiberoptic bronchoscopy, which confirmed the diagnosis of MKS. By reviewing the literature via PubMed, we conducted a retrospective analysis of 29 previously reported cases of MKS, including the present case, totaling 30 cases (21 males and 9 females), predominantly middle-aged and elderly individuals. CONCLUSIONS: Based on our literature review, the misdiagnosis rate of MKS remains high, often accompanied by significant diagnostic delays. Additionally, the proportion of secondary MKS cases has increased, challenging the traditional notion that MKS is exclusively congenital. Despite its rarity, clinicians should consider MKS in patients presenting with recurrent lower respiratory tract infections, abnormal tracheobronchial morphology., poor response to antibiotic therapy, or refractory COPD-like symptoms. Early imaging and bronchoscopic evaluations are essential to confirm the diagnosis and prevent delayed treatment.