Benign subglottic stenosis from a rheumatologist' perspective: a narrative review

Subglottic stenosis (SGS) is an umbrella term referring to a collection of rare diseases resulting in narrowing of the proximal airway directly below the glottis. SGS can follow iatrogenic injury (e.g., endotracheal intubation), can occur without antecedent injury (idiopathic SGS: iSGS), and can accompany autoimmune disease (e.g., Granulomatosis with Polyangiitis: GPA, Relapsing Polychondritis: RP). SGS is life-altering and life-threatening. Proximal airway obstruction generates dyspnea, limits exercise tolerance, and negatively impacts voicing. Taken together, SGS significantly reduces quality of life. Given its rarity, the diagnosis of SGS is often delayed. Fortunately, advances in our understanding of SGS have grown rapidly in recent years, aided by the widespread use of clinical testing. Useful diagnostic tools include pulmonary function testing, flexible endoscopy, computed tomography, laboratory testing, and pathology results. Treatment options are dependent on the underlying disease etiology but frequently involve endoscopic dilation. Especially in iSGS, invasive surgical options (cricotracheal resection (CTR)) are reserved for specific surgical candidates. While CTR can provide durable benefit, it has a significant risk profile and is not always curative. Alternative treatments which limit recurrent obstructive scar and decrease the need for repeated dilations are critical goals of the iSGS patient community. Although there is an established role for immunosuppressive agents in GPA and RP, solid proof of efficacy for immunosuppressive treatment in iSGS is lacking. New approaches have begun to investigate the role of adjuvant therapy in this patient subgroup. This article provides rheumatologists with the latest insights on the etiology, pathophysiology, diagnostic evaluation, and treatment of SGS.