A Clinical Classification Scheme for Tracheobronchomegaly (Mounier-Kuhn Syndrome)

• Published in: Lung Vol. 193; no. 5; pp. 815 - 822
• Main Authors: Payandeh, Jennifer, McGillivray, Barbara, McCauley, Graeme, Wilcox, Pearce, Swiston, John R., Lehman, Anna
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.10.2015; Springer; Springer Nature B.V
• Subjects: Care and treatment; Classification; Clinical trials; CT imaging; Cutis Laxa - complications; Fetoscopy - adverse effects; Fibers; Humans; Infant; Intubation, Intratracheal - adverse effects; Lung diseases; Male; Medicine; Medicine & Public Health; Middle Aged; Patients; Pneumology/Respiratory System; Pulmonary Fibrosis - complications; Respiratory Tract Infections - complications; Tracheobronchomegaly - classification; Tracheobronchomegaly - etiology; United States; Acquired cutis laxa; Mounier-Kuhn syndrome; Connective tissue diseases; Generalized elastolysis; Tracheobronchomegaly
• DOI: 10.1007/s00408-015-9757-z
• ISSN: 0341-2040

Introduction Tracheobronchomegaly (Mounier-Kuhn Syndrome) is a rare disease characterized by tracheal enlargement and associated loss of elastic fibers in the trachea and main bronchi. Materials MEDLINE, Index Medicus, and other databases were searched with pre-defined criteria to identify cases of tracheobronchomegaly (TBM). Two new cases of TBM were also identified from the Provincial Medical Genetics Program of British Columbia. Results We identified 166 publications describing 365 occurrences of TBM. We observed that affected individuals could be grouped into subgroups according to clinical features. Type 1A (105 individuals) consists of infants who developed TBM after having undergone fetoscopic tracheal occlusion, and Type 1B patients (24 individuals) are infants and children who developed TBM after prolonged intubation. Type 2 individuals developed TBM following recurrent pulmonary infections (2A) (14 individuals) or pulmonary fibrosis (2B) (10 individuals). Type 3 represents TBM with evidence of extra-pulmonary elastolysis (18 individuals), and Type 4 denotes the development of TBM with no clear predisposing factors (196 individuals). Both of our patients had TBM and evidence of extra-pulmonary elastolysis. As well, one patient had a mildly dilated aortic root, which is a previously unreported co-occurrence. Conclusion We introduce a novel classification scheme, which may sort patients into etiologically distinct groups, furthering our understanding of its pathogenesis and potentially, prevention or therapy. We also hypothesize that TBM and generalized elastolysis may have etiological commonalities, suggesting a need for further study.