Tracheobronchomegaly (Mounier-Kuhn Syndrome) in a 43-Year-Old Male: A Case Report

Abstract

Mounier-Kuhn syndrome (MKS) or congenital tracheobronchomegaly is a rare disorder characterized by marked dilatation of the trachea and main bronchi, bronchiectasis, and recurrent respiratory tract infections. The etiology of this disorder is uncertain and the clinical presentation is variable. The diagnosis is usually made based on the characteristic computed tomography (CT) scan findings. This report describes a case of a 43-year-old man presenting with persistent cough and recurrent lower respiratory tract infections since childhood associated with copious amounts of purulent sputum, difficulty in breathing, and weight loss. In addition, he reported palpitations, dyspnea, orthopnea, abdominal and lower limb swelling. The chest X-ray showed a dilated trachea (35mm) and bronchi (26mm (right) and 27mm (left)) with cystic bronchiectasis and reticulolinear opacities predominantly involving the middle and lower lung zones. Chest CT scan confirmed the diagnosis of MKS as evidenced by dilated trachea and bronchi complicated by diverticula formation. Electrocardiogram, echocardiography and abdominal ultrasound scan showed features of right-sided heart failure secondary to pulmonary hypertension. MKS, although rare, should be considered as a possible diagnosis in patients presenting with productive chronic cough, recurrent pneumonia, or incomplete response to appropriate antibiotic therapy for pneumonia.

Keywords: MKS; Mounier-Kuhn syndrome; tracheobronchomegaly.

Figure 1

General physical examination findings in a man with Mounier Kuhn Syndrome: (A) shows wasting and mild abdominal distension due to ascites, (B) shows grade 3 digital clubbing, (C) shows pitting oedema after removing stockings.

Figure 2

Chest x-ray images AP (A) and lateral (B), showing the dilated trachea (block arrow) and right principal bronchus (notched arrow) with diffuse reticulolinear opacities and cystic bronchiectasis of the lower lung zones.

Figure 3

Axial CT images (A) is soft tissue window demonstrating a dilated trachea (measurement calipers) and (B) is a lung window demonstrating a tracheal diverticulum (arrow).

Figure 4

Coronal CT scans, lung window: (A) demonstrates the grossly dilated and tortuous principal bronchi (measurement calipers), Right bronchus measures 4.25cm and left bronchus measures 3.81cm; (B) demonstrates cystic and varicose bronchiectasis.

Figure 5

CT images lung window: (A) demonstrating ground glass opacities and bronchiectasis in the right middle lobe (blue arrow) and (B) demonstrating mucus filled bronchi with air fluid levels (orange arrows).