A CASE OF TRACHEOBRONCHIAL AMYLOIDOSIS PRESENTING AS SYNCOPE

ABSTRACT

SESSION TITLE Systemic Diseases with Deceptive Pulmonary Manifestations SESSION TYPE Rapid Fire Case Reports PRESENTED ON 10/18/2022 1225 pm - 0125 pm INTRODUCTION: Amyloidosis of the respiratory tract is rare. We present a case of tracheobronchial amyloid presenting as multifactorial cough with syncope. CASE PRESENTATION The patient is a 65-year-old man with history of hypertension, hyperlipidemia, and allergic rhinitis who presented to the ED after a syncopal event. Two weeks prior, he had a new-onset myalgias and severe persistent cough, not resolving with over-the-counter medications. During a coughing paroxysm, he experienced a brief loss of consciousness. On arrival, his vital signs and physical exam were within normal limits except for Mallampati II, BM of 38.8 kg/m2. Basic laboratory testing was also unremarkable except for troponin T of 251 nl/dL and NT-ProBNP of 1181 pg/mL. NP swab for Sars-CoV-19 (PCR), Influenza A and B were not detected. CT of the chest revealed an area of circumferential mural soft tissue thickening in the left lower lobe bronchi. Cardiac MRI showed an area of subepicardial delayed enhancement, suggestive of myocardial inflammation or edema. Flexible bronchoscopy confirmed that the left lower lobe bronchus and proximal subsegmental bronchi had an infiltrative process with a friable, erythematous irregular mucosal surface. Forceps biopsy sampling and staining with Congo red, sulfate Alcian blue and Trichome stain were positive for amyloid deposits. Immunostain revealed predominantly CD3 positive T-Cells. Mass spectometry showed AL (lamda)-type amyloid deposition. GMS and AFB stains were negative. Telemetry showed 2-3 second pauses, correlated with episodes of cough. DISCUSSION: Amyloidosis is a disorder caused by misfolding of proteins and fibril accumulation in the extracellular space. It can present as a diffuse or localized process to one organ system. Several patterns of lung involvement have been described nodular pulmonary, diffuse alveolar-septal, cystic, pleural, and tracheobronchial amyloidosis. Tracheobronchial amyloidosis is usually limited and not associated with systemic disease or hematologic malignancy. It can be asymptomatic, or can present with cough, dyspnea or signs of obstruction, including postobstructive pneumonia. Congo Red stained samples reveal green birefringence under polarized light microscopy. Further analysis of proteins usually reveals localized immunoglobulin light chains (AL). Cough syncope is due to increased intrathoracic pressure, decreased venous return and cardiac output, stimulation of baroreceptors, decreased chronotropic response, arterial hypotension and decreased cerebral perfusion. Our patient presented with multifactorial cough (possible viral infection, upper airway cough syndrome, amyloidosis) causing sinus pauses and syncope, on underlying myocarditis. CONCLUSIONS: Amyloid infiltration of the respiratory system is rare, but it should be considered in the differential diagnosis of airway disorders, nodular or cystic lung diseases, and pleural processes. Reference #1 Milani P, Basset M, Russo F, et al. The lung in amyloidosis. Eur Respir Rev 2017;26 170046 [https//doi.org/10.1183/16000617.0046-2017]. Reference #2 Utz JP, Swensen SJ, Gertz MA. Pulmonary amyloidosis. The Mayo Clinic experience from 1980 to 1993. Ann Intern Med. 1996 Feb 15;124(4)407-13. doi 10.7326/0003-4819-124-4-199602150-00004 Reference #3 Dicpinigaitis PV, Lim L, Farmakidis C. Cough syncope. Respir Med. 2014 Feb;108(2)244-51. doi 10.1016/j.rmed.2013.10.020. Epub 2013 Nov 5. PMID 24238768. DISCLOSURES No relevant relationships by Amarilys Alarcon-Calderon No relevant relationships by Ashokakumar Patel