C44-15 Beyond the Wheeze: Unmasking Congenital Lung Hypoplasia and Bronchial Stenosis Misdiagnosed as Asthma

Abstract Introduction Congenital lung and airway abnormalities are rare, often presenting with chronic or recurrent respiratory symptoms that mimic common pulmonary conditions such as asthma or pneumonia. The incidence of congenital lung hypoplasia is approximately 1-2 cases per 12,000 births; however, its true prevalence may be higher, particularly in under-resourced settings where diagnostic delays and misdiagnoses contribute to chronic infection, inflammation, and irreversible lung damage. Case Report We present a 20-year-old male with a history of tobacco use, recurrent sinopulmonary infections and presumed asthma, who presented with worsening productive cough and progressive dyspnea over several months. Additionally, he experienced significant weight loss of 40 lbs accompanied by a marked decline in functional status. He was managed as an asthma exacerbation complicated by pneumonia, receiving multiple courses of antibiotics, nebulized bronchodilators, and systemic corticosteroids, resulting in only partial symptom resolution. Born prematurely, he had a longstanding history of presumed asthma treatment, compounded by limited healthcare access associated with recurrent episodes of incarceration. A CT of the thorax demonstrated a hypoplastic left lung with near-complete atelectasis and severe bronchiectasis. Given these findings, bronchoscopy was performed. Flexible bronchoscopy identified a 90% intrinsic, mucosal-based stenosis of the left mainstem bronchus, with copious distal mucopurulent secretions. Therapeutic rigid bronchoscopy with balloon dilation was performed, followed by placement of a 12mm x 15mm Aero stent in the proximal left lower lobe bronchus. Post-intervention, the combination of airway clearance therapies and bronchial stenting demonstrated significant clinical improvement. The final diagnosis was congenital left lung hypoplasia associated with congenital left mainstem bronchial stenosis, exacerbated by tobacco use, and chronic inflammatory injury secondary to recurrent infections. Six weeks later, the productive cough had almost completely resolved. Additionally, the patient reported weight gain, enhanced activity tolerance, and improved left lung aeration on follow-up CT imaging performed at six weeks. Discussion This case emphasizes the critical importance of revisiting chronic or recurrent pulmonary diagnoses when clinical response to standard therapy is inadequate or incomplete. Rare congenital pulmonary abnormalities, including lung hypoplasia and airway stenosis, may present deceptively as common respiratory conditions, particularly in populations with limited healthcare resources. Timely utilization of advanced imaging and bronchoscopy was pivotal in achieving the correct diagnosis and enabling effective therapeutic interventions. Early identification and management of airway obstruction can substantially improve respiratory symptoms, reduce chronic infection burden, and enhance overall quality of life. This abstract is funded by: None