SEVERE TRACHEOBRONCHOMALACIA IN AN END-STAGE RENAL DISEASE PATIENT REFERRED FOR KIDNEY TRANSPLANT EVALUATION

Abstract

SESSION TITLE: Medical Student/Resident Obstructive Lung Disease Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Tracheobronchomalacia (TBM) is characterized by loss of the integrity of the central airway wall cartilaginous structures resulting in hyper-dynamic airway collapse. In adults, TBM is either idiopathic or associated with other conditions. We present a case of severe TBM in a patient with end stage renal disease undergoing evaluation for kidney transplant. CASE PRESENTATION: A 45-year-old male with history of type one diabetes mellitus, end stage renal disease on hemodialysis and chronic obstructive pulmonary disease (COPD) diagnosed without Pulmonary function testing (PFT). He was referred for pulmonary evaluation prior to kidney transplant. He had history of recurrent pneumonia, coughing with choking sensations and high-pitched wheezing that resolved after expectoration of scant thick phlegm. He denied tobacco use, chemical exposures, or asthma. PFT revealed severe obstruction with FEV1/FVC ratio of 43.2 and FEV1 1.71 Liter. The loops showed small volumes and flattening of the expiratory loops (Figure 1). Computerized tomography (CT) scan of the chest showed crescentic deformity of the trachea and bilateral mainstem bronchi (Figure 2) consistent with TBM. He was started on airway clearance therapy with flutter valves and albuterol nebulization. Non-invasive-positive pressure ventilation (NIPPV) was denied due to unconventional indication. Shortly after outpatient evaluation, he was re-admitted for severe pneumonia requiring invasive mechanical ventilation. He failed extubation. Tracheal stent placement was unsuccessful due to intraprocedural episodes of desaturation and stent dislodgement. Percutaneous tracheostomy was performed and he was successfully weaned off mechanical ventilation. He uses cuffless tracheostomy tube and has not had pneumonia since. Unfortunately, he is not a transplant candidate due to his pulmonary disease. DISCUSSION: TBM is commonly mistaken as COPD or asthma due to the similarities in symptoms and obstructive pattern on spirometry. The gold standard for confirmation is flexible bronchoscopy and visualization of more than 50% dynamic airway collapse. 51-75% is considered mild obstruction, 76 - 90% moderate and greater than 90% is severe. Dynamic CT can be used quantify the severity of the TBM with a strong correlation. The initial treatment involves the use of bronchodilators and airway hygiene. If these fails, then NIPPV is used. The next intervention would be stenting or tracheostomy which splints the airways. Tracheobronchoplasty is a surgical option when stenting have shown significant symptoms improvement. CONCLUSIONS: This case highlights the importance of having a wide differential diagnosis when evaluating patients. A close look at the PFT flow-volume loops led us towards the diagnosis. Reference #1: Beckerman, Z. at al. Tracheobronchomalacia: Does One Size Fit All? Semin Thorac Cardiovasc Surg, 2019. 31(3): p. 486-487. Reference #2: Biswas, A., et al., Tracheobronchomalacia. Dis Mon, 2017. 63(10): p. 287-302. Reference #3: Uyar, M., et al., Tracheobronchomalacia as a Rare Cause of Chronic Dyspnea in Adults. Med Princ Pract, 2017. 26(2): p. 179-181. DISCLOSURES: No relevant relationships by RAMYA GORTHI, source=Web Response No relevant relationships by Stephanie Link, source=Web Response No relevant relationships by John Mwangi, source=Web Response