An Updated Review of Subglottic Stenosis: Etiology, Evaluation, and Management

Abstract

Purpose of ReviewTo assimilate the newly published literature regarding subglottic stenosis (SGS), including basic science and translational research on mechanisms of etiology, clinical diagnostics, and therapeutic treatments. Recent FindingsThe role of inflammation in development of iatrogenic and idiopathic SGS (iSGS) is continuing to be studied. The IL-23/IL-17A inflammatory axis appears to be a potential mechanism for development of iSGS. Additionally, as anticipated in an inflammatory milieu, PD-1/PD-L1 expression is upregulated. If the PD-1/PD-L1 axis is important in SGS pathogenesis, then it may represent a potential target for immunotherapeutic inhibition, given its success in cancer treatment. In terms of surgical management, prospective studies show that endoscopic approaches have more frequent recurrence compared to open techniques. Summary SGS arises from various etiologies, and further understanding of its pathogenesis can aid in the development of novel therapies. It is imperative to obtain a thorough history for each patient presenting with respiratory complaints, as misdiagnosis can delay proper treatment. Endoscopic and open surgical techniques continue to be investigated in a growing number of prospective clinical trials to determine optimal treatment protocols. In-office injections are gaining popularity and show promise in the treatment of SGS.

A Novel Grading System for Supraglottic Stenosis Based on Morphology and Functional Status

“…4 The second most common cause of supraglottic stenosis in this cohort was iatrogenic instrumentation or intubation, which is unlike previously reported data for supraglottic stenosis but similar to data reported for glottic and subglottic stenosis. 8 The other etiologies seen in our cohort are also consistent with what has been previously reported in the literature, including the rare infectious cause of klebsiella rhinoscleromatis. 9 Supraglottic stenosis has also been described in the pediatric otolaryngology literature.…”

“…Like previously reported data, external‐beam radiation was the most common etiology of supraglottic stenosis in this series 4 . The second most common cause of supraglottic stenosis in this cohort was iatrogenic instrumentation or intubation, which is unlike previously reported data for supraglottic stenosis but similar to data reported for glottic and subglottic stenosis 8 . The other etiologies seen in our cohort are also consistent with what has been previously reported in the literature, including the rare infectious cause of klebsiella rhinoscleromatis 9 …”

Atypical distal tracheal fibrous bridge and bronchial stenosis in an adult patient with bronchopulmonary dysplasia

“…Depending on the level of TBS, obstruction can result in long-term pulmonary issues, such as recurrent pneumonia, emphysema, or atelectasis. 1,2 Our case was unique as a fibrous bridge was encountered in the distal trachea, with fibrous stenosis in the RMB and LMB. This kind of structure has been scarcely reported in the literature, with only one other case report describing similar tracheal fibrotic bridges secondary to prolonged intubation and tracheostomy post-COVID-19 infection.…”

“…6 Multiple modalities are present to diagnose TBS, including chest CT, magnetic resonance imaging, and endoscopy, the gold standard. 1,2 Bronchoscopy also doubles as a therapeutic tool to relieve the obstruction. Surgery for TBS is usually reserved for more advanced cases and, most commonly, bronchogenic carcinomas.…”

Subglottic stenosis misdiagnosed as asthma: a case report

“…Iatrogenic SGS, caused by intubation or tracheostomy, was first theorized in 1969, and thought to be the result of tracheal ischaemia due to high endotracheal cuff pressures compromising the mucosal blood flow, leading to subglottic scarring and fibrosis. 3,4 Subglottic stenosis can lead to life-threatening conditions such as reduced ventilation, and can lead to respiratory failure and death.…”