A case of Mounier-Kuhn syndrome in a geriatric patient

Abstract

Mounier-Kuhn syndrome, or tracheobronchomegaly, is a rare clinical and radiologic condition characterized by marked tracheobronchial dilation and recurrent lower respiratory tract infections. The syndrome was first described by Mounier-Kuhn in 1932, and few cases have been reported in the medical literature [1]. The clinical presentation varies widely, from asymptomatic disease with preserved lung functions to recurrent chest infections, exertional dyspnoea to even respiratory failure in severe cases. Diagnosis is often made by using CT, through which abnormally large air passages are detected. In adults, the diagnostic criteria are diameters of the trachea >30 mm, right main bronchus >20 mm and of the left main bronchus >18 mm [2-4]. Upon pulmonary function testing, decreased bronchial flow speed, increased tidal volume, and dead spaces may be observed. Bronchoscopy can detect the pathologic processes that affect the tracheobronchial structures. Connective-tissue diseases, ataxia-telangiectasia, ankylosing spondylitis, EhlersDanlos syndrome, Marfan syndrome, Kenny-Caffey syndrome, Brachmann-de Lange syndrome, and cutis laxa (elastolysis) are also associated with secondary tracheobronchial enlargement [2-5]. All these conditions should be considered in the differential diagnosis.