A RARE CASE OF CONGENITAL TRACHEOBRONCHOMEGALY (MOUNIER-KUHN SYNDROME) IN A 28-YEAR-OLD ZAMBIAN MALE

TYPE: Case Report TOPIC: Diffuse Lung Disease INTRODUCTION: Congenital tracheobronchomegaly, also known as Mounier Kuhn Syndrome (MKS) is a rare respiratory disorder characterized by dilatation of the trachea and bronchi. We report a case of a 28 year old male of African descent in Zambia. CASE PRESENTATION: A 28-year-old HIV-negative male presented with recurrent respiratory tract infections for 14 years associated with an occasional wheeze and exertional dyspnea. He reported exposure to cement as a construction worker and a 5 pack-year smoking history. He had been treated numerous times for lower respiratory tract infections, and had received empiric tuberculosis (TB) treatment based on chest radiograph findings. Investigations revealed normal baseline blood results and sputum results. He however had markedly increased levels of serum Immunoglobulin E and spirometry showed an obstructive pattern with significant post bronchodilator improvement. High-resolution computed tomography scan (HRCT) revealed tracheal dilatation, extensive bilateral bronchiectasis and tracheal and bronchial diverticuli which were also seen on bronchoscopy, confirming the diagnosis of Mounier-Kuhn Syndrome. The patient was treated with combined inhaled corticosteroids and bronchodilators as well as chest physiotherapy for mucus clearance. DISCUSSION: MKS can be diagnosed radiologically when HRCT reveals tracheobronchomegaly with diverticula. The main problems associated with MKS are recurrent lower respiratory tract infections that ultimately complicate into bronchiectasis. Treatment of MKS is mainly supportive.Our case highlights how in low-resource settings, bronchiectasis, is often mistaken for and presumptively treated as TB due to the great overlaps in presentation and the absence of better diagnostic tools and multidisciplinary diagnostic teams. CONCLUSIONS: MKS should be considered as a rare cause of bronchiectasis. DISCLOSURE: Nothing to declare. KEYWORD: Mounier-Kuhn