Coughing up a lung? Expectoration of obstructive fibrinous tracheal pseudomembrane

ABSTRACT

Case Report Most common causes of shortness of breath are asthma, COPD, CHF, pulmonary embolism, diffuse lung parenchymal diseases and obesity hypoventilation syndrome. Rare conditions can be bronchiectasis, constrictive pericarditis, kyphoscoliosis, tracheomalacia, cardiomyopathies and so on. We present a rare case of tracheal stenosis presenting with repeated hospital admissions followed by intubations and resolution after spontaneous expectoration. A 52-year-old female with a history of end stage renal disease on hemodialysis, resistant hypertension, and COVID pneumonia on supplemental oxygen, presented with dyspnea associated with yellowish productive sputum for one day. She was admitted one week prior due to the same complaint associated with encephalopathy due to hypercapnia, required endotracheal intubation, got extubated four days later, was provisionally diagnosed with asthma and volume overload, and discharged home. During the admission of interest, the patient's examwas normal except severe hypertension with BP of 192/101, bilateral crackles and rhonchi. Arterial blood gasses (ABGs) again showed hypercapnia. CT thorax showed evidence of left lower lobe pulmonary infiltrate and ground-glass opacities. Due to repeated admissions for hypercapnic respiratory failure, suspicion for persistent anatomic or pathologic abnormality was high. Reexamination of CT thorax suggested subglottic stenosis and she underwent fiberoptic laryngoscopy which revealed grade 3 subglottic stenosis. On day three, she became hypoxic and unresponsive, ABGs revealed PCO2 of 150, and got intubated again. Soon after intubation, the patient had spontaneous expectoration of a large piece of firm, fleshy, blood-tinged, thick, luminal tissue. On the histologic examination, the material was found to be a plug of fibrin with small to moderate numbers of inflammatory cells embedded in the matrix. Follow-up CT neck and chest revealed resolution of previously visualized tracheal stenosis. She underwent repeat direct laryngoscopy and flexible bronchoscopy which did not show any tracheal stenosis. The patient remained hemodynamically stable and was discharged home. Tracheal stenosis is challenging to diagnose. Examples of tracheal stenosis due to pseudomembrane formation are rare in medical literature, and the expectoration of fibrin material after intubation in a person with this condition is even rarer. A similar case has been described before with an identical situation of coughing up soft tissue and comparable histopathology report. Our case highlights the importance of critical analysis for broad differentials, adding up pieces of the puzzle to explain the missing link. This patient came with recurrent episodes of dyspnea that were misdiagnosed as volume overload, pneumonia, and asthma exacerbations. CT chest findings of possible subglottic stenosis were the missing link in this case which steered further work-up and led to the final diagnosis. Copyright © 2023 Southern Society for Clinical Investigation.