ANCA-negative granulomatosis polyangiitis: an airway emergency.

Granulomatosis polyangiitis (GPA) is an autoimmune condition causing inflammation of small blood vessels. It is a rare disorder that may affect various parts of the body. The diagnosis is often based on clinical examination, laboratory investigations and tissue biopsy. In about 10-20% of patients, the anti-neutrophilic cytoplasmic antibody (ANCA) can be negative, and histology maybe inconclusive, which can lead to diagnostic uncertainty. Failure to treat vasculitis can lead to morbidity and even mortality. We present a case report of a gentleman who was presented with an airway emergency with inflammation of the nasal cavity and subglottic involvement amounting to airway stenosis. His ANCA was negative and tissue biopsy from the subglottis was inconclusive. He underwent urgent dilatation of his airway, local therapies to the nose and was commenced on 10 cycles of cyclophosphamide. A follow-up of over 4 years has not shown any relapse of his disease clinically or biochemically. We discuss the clinical findings, diagnostic dilemma and multidisciplinary management of this life-threatening condition.

Airway and Ventilator Management in a New Presentation of Idiopathic Subglottic Stenosis: A Case Report.

In the acute setting, subglottic stenosis poses a unique airway management challenge, particularly when presenting to a facility where subspecialty care is not available. We present a case of idiopathic subglottic stenosis with acute respiratory distress managed at a community hospital to highlight the challenges of diagnosis, initial airway management, and mechanical ventilation of this rare but life-threatening condition.

Using Machine Learning for Endoscopic Detection of Low-Grade Subglottic Stenosis: A Proof of Principle.

The current study trains, tests, and evaluates a deep learning algorithm to detect subglottic stenosis (SGS) on endoscopy. A retrospective review of patients undergoing microlaryngoscopy-bronchoscopy was performed. A pretrained image classifier (Resnet50) was retrained and tested on 159 images of airways taken at the glottis, 106 normal-sized airways, and 122 with SGS. Data augmentation was performed given the small sample size to prevent overfitting. Overall model accuracy was 73.3% (SD: 3.8). Precision and recall for stenosis were 77.3% (SD: 4.0) and 72.7 (SD: 4.0). F1 score for the detection of stenosis was 0.75 (SD: 0.04). Precision and recall for normal-sized images were lower at 69% (SD: 4.35) and 74% (SD: 4), with an F1 score of 0.71 (SD: 0.04). This study demonstrates that an image classification algorithm can identify SGS on endoscopic images. Work is needed to improve diagnostic accuracy for eventual deployment of the algorithm into clinical care.

Congenital glottic stenosis as a clinical manifestation of FREM1-associated disorders in a neonate with respiratory distress and aphonia.

A female infant born at 38 weeks and 2 days via induced vaginal delivery was admitted to the neonatal intensive care unit for respiratory distress soon after birth. Noted to have aphonia on examination, the patient underwent direct laryngoscopy and was diagnosed with an anterior glottic web and subglottic stenosis. The patient underwent a genetic workup including whole exome sequencing which resulted in a diagnosis of a FREM1-associated disorder. Congenital glottic webs and subglottic stenoses have not been previously described as clinical manifestations of FREM1-associated disorders.

Assessing the interrater and intrarater reliability of subglottic stenosis grading systems.

BACKGROUND: Subglottic stenosis (SGS) is a condition leading to narrowing of the upper airway which can lead to dyspnea and life-threatening airway obstruction. Although other proposed grading systems exist, the Cotton Myer (CM) and percent stenosis systems are the most widespread in clinical practice. Despite this, the CM system has not yet been validated for visual assessment of SGS. OBJECTIVE: To determine the interrater and intrarater reliability of the CM grading system among a cohort of physicians who manage patients with SGS. METHODS: An online survey created with videos of tracheoscopies from 20 adult patients with subglotticstenosis (SGS) was sent individually to 9 expert physicians from various medical specialties, all of whom managed patients with SGS. Physicians were asked to view the 20 tracheoscopy videos and assess both the percent stenosis and Cotton Myer (CM) grade of each patient. After a period of 4 weeks, the physicians were sent the same survey of the 20 tracheoscopy videos. The interrater and intrarater reliability was calculated using the intraclass correlation coefficient (ICC), a measurement used to evaluate the reliability (the extent to which a measurement can be replicated) of two or more raters measuring the same subject. RESULTS: Overall, CM and percent stenosis systems were found to have an ICC of 0.94 and 0.90 within the domain of interrater reliability, respectively, and ICC of 0.71 and 0.81 within the domain of intrarater reliability, respectively. CONCLUSION: Our findings suggest that the CM and percent stenosis grading systems remain a valid clinical tool to measure and communicate the severity of airway obstruction in SGS.

[Balloon dilation as an alternative to tracheotomy for acquired subglottic stenosis in children of the first year of life]. / Ballonnaya dilatatsiya kak al'ternativa trakheotomii pri priobretennom podskladkovom rubtsovom stenoze u detei pervogo goda zhizni.

OBJECTIVE: To study the efficacy and safety of balloon dilation as the first choice method in the treatment of children of the first year of life with acquired subglottic stenosis. MATERIAL AND METHODS: A retrospective analysis of the treatment of 25 patients aged 27 days to 11 months of life (average age 5.3±3.76 months) with subglottic stenosis caused by prolonged intubation, in whom balloon dilation was the first method of treatment. Grade III Cotton-Myer stenosis was preoperatively detected in 22 children, the remaining 3 had grade II stenosis. RESULTS: The success rate of balloon dilation was 100%; tracheotomy was not required in any case, the absence of stenosis during a follow-up examination in the catamnesis was recorded in 14 (56%) children, the remaining 11 (44%) had grade 0-I stenosis and did not cause respiratory disorders. In 1 child (1.5 years old), a subglottic cyst was removed after balloon dilation. One dilation was required in 18 (72%) children, two - in 5 (20%), three and four - respectively for 1 patient. If additional intervention was necessary, the operation was repeated 10 days - 3 months after the previous one. There were no postoperative complications. CONCLUSION: Balloon dilation is a highly effective and safe alternative to traditional surgical interventions for acquired subglottic stenosis in children of the first year of life and can be recommended as a method of first choice.

[Idiopathic Subglottic Tracheal Stenosis]. / Idiopathische subglottische Tracheastenose.

Idiopathic subglottic stenosis is a circular scarred narrowing of the airway at the transition from the cricoid cartilage to the trachea. The stenosis is found radiologically and endoscopically at the level of the cricoid cartilage without involvement of the cricoid or tracheal cartilage itself. The disease practically only affects women between the ages of 20 and 60. The same clinical picture occurs in granulomatosis with polyangiitis and less frequently in other autoimmune diseases, where it requires systemic treatment. The clinical picture usually begins insidiously with coughing and sputum production and leads to dyspnoea and a restricted cough. As the course is insidious and the patients are otherwise healthy, the symptoms are often misinterpreted and the diagnosis is delayed. Treatment consists of local measures, ranging from dilatation and laser surgical resection, sometimes with local application of medication to inhibit the proliferation of new scar tissue, to laryngotracheal resection of varying degrees. The disease is located in the border area between the trachea and larynx and the patients are therefore treated by ENT medicine, pneumology and thoracic surgery.

Navigating Pathways to Diagnosis in Idiopathic Subglottic Stenosis: A Qualitative Study.

OBJECTIVE: Idiopathic subglottic stenosis is a rare disease, and time to diagnosis is often prolonged. In the United States, some estimate it takes an average of 9 years for patients with similar rare disease to be diagnosed. Patient experience during this period is termed the diagnostic odyssey. The aim of this study is to use qualitative methods grounded in behavioral-ecological conceptual frameworks to identify drivers of diagnostic odyssey length that can help inform efforts to improve health care for iSGS patients. METHODS: Qualitative study using semi-structured interviews. Setting consisted of participants who were recruited from those enrolled in a large, prospective multicenter trial. We use directed content analysis to analyze qualitative semi-structured interviews with iSGS patients focusing on their pathways to diagnosis. RESULTS: Overall, 30 patients with iSGS underwent semi-structured interviews. The patient-reported median time to diagnosis was 21 months. On average, the participants visited four different health care providers. Specialists were most likely to make an appropriate referral to otolaryngology that ended in diagnosis. However, when primary care providers referred to otolaryngology, patients experienced a shorter diagnostic odyssey. The most important behavioral-ecological factors in accelerating diagnosis were strong social support for the patient and providers' willingness to refer. CONCLUSION: Several factors affected time to diagnosis for iSGS patients. Patient social capital was a catalyst in decreasing time to diagnosis. Patient-reported medical paternalism and gatekeeping limited specialty care referrals extended diagnostic odysseys. Additional research is needed to understand the effect of patient-provider and provider-provider relationships on time to diagnosis for patients with iSGS. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:815-824, 2024.

The Subglottic Stenosis 6 Questionnaire: A Novel Quality-of-Life Survey Validated to Predict Need for Intervention in Patients With Idiopathic Subglottic Stenosis.

BACKGROUND: Idiopathic subglottic stenosis (iSGS) is a recurrent, chronic disease defined by fibroinflammatory narrowing of the subglottic airway. A key challenge in treatment is monitoring disease progression, which may be debilitating and unpredictable in its timing. RESEARCH QUESTION: Can the Subglottic Stenosis 6 (SGS-6) questionnaire be validated as a novel quality-of-life (QOL) instrument to monitor breathing, disease progression, and disease severity proactively in patients with iSGS? STUDY DESIGN AND METHODS: Panel data from 51 patients with iSGS were collected from January 2012 through June 2022, representing 1,684 patient encounters including routine office visits and treatment encounters. Subjective QOL scores (including the novel SGS-6 and established RAND-36 and EuroQol Five Dimensions [EQ-5D] Visual Analog Scale) and objective pulmonary function test (PFT) results were collected at each visit. Subjective SGS-6 QOL scores were repeated within 1 week of initial reporting. Panel regression analyses were performed to assess the relationship between SGS-6 scores, PFT results, and a patient's need for intervention. Minimal clinically important differences (MCIDs) for SGS-6 and peak expiratory flow percentage (PEF%) were assessed using receiver operating characteristic (ROC) curve analysis and a patient's need for intervention as the external anchor. RESULTS: Each one-point increase in SGS-6 score (of a maximum of 27) was associated with a 3.26% decrease in PEF%, a 1.93-point decrease in RAND-36 Physical Health composite score, a 1.27-point decrease in RAND-36 Mental Health composite score, and a 0.88-point decrease in EQ-5D Visual Analog Scale score. The intracorrelation coefficient for the SGS-6 composite score is 0.838 (95% CI, 0.770-0.888). Compared with patient baselines, SGS-6 scores were 4.66 points greater at the time of intervention with an MCID of 2.25 from a patient's baseline. The area under the ROC curve for SGS-6 and a patient's intervention point was 0.81. INTERPRETATION: iSGS disease severity can be modeled using the SGS-6 questionnaire, offering physicians and patients a potentially new method of tracking disease progression and need for intervention remotely.

The diagnostic accuracy of spirometry as screening tool for adult patients with a benign subglottic stenosis.

BACKGROUND: There is a considerable diagnostic delay in the diagnosis 'benign acquired subglottic stenosis in adults' (SGS, diagnosed by the reference standard, i.e. laryngo- or bronchoscopy). Patients are frequently misdiagnosed since symptoms of this rare disease may mimic symptoms of 'asthma.' The 'Expiratory Disproportion Index' (EDI) obtained by spirometry, may be a simple instrument to detect an SGS-patient. The aim of this study was to evaluate the diagnostic accuracy of the EDI in differentiating SGS patients from asthma patients. METHODS: We calculated the EDI from spirometry results of all SGS-patients in the Leiden University Medical Center (LUMC), who had not received treatment 2 years before their spirometry examination. We compared these EDI results with the EDI results of all true asthma patients between 2011 and 2019, who underwent a bronchoscopy (exclusion of SGS by laryngo- or bronchoscopy). RESULTS: Fifty patients with SGS and 32 true asthma patients were included. Median and IQR ranges of the EDI for SGS and asthma patients were 67.10 (54.33-79.18) and 37.94 (32.41-44.63), respectively. Area under the curve (ROC) of the accuracy of the EDI at discriminating SGS and asthma patients was 0.92 (95% CI = 0.86-0.98). The best cut-off point for the EDI was > 48 (i.e. possible upper airway obstruction), with a sensitivity of 88.0%% (95%CI = 77.2-95.0%%) and specificity of 84.4% (95%CI = 69.4-94.1%). CONCLUSIONS: The EDI has a good diagnostic accuracy discriminating subglottic stenosis patients from asthma patients, when compared to the reference standard. This measurement from spirometry may potentially shorten the diagnostic delay of SGS patients. Further studies are needed to evaluate clinical reproducibility.

[Surgical treatment of postintubation stenosis of the larynx in children]. / Khirurgicheskoe lechenie postintubatsionnykh stenozov gortani u detei.

Post-intubation laryngeal stenosis is the most common cause of upper respiratory obstruction in children. According to published data, the incidence of post-intubation stenosis ranges from 0.1 to 20%. Treatment of children with chronic laryngeal stenosis is a special branch of respiratory surgery. It remains one of the most complex and urgent problems in pediatrics, pediatric otorhinolaryngology, and pediatric surgery. Although numerous studies have described various methods for treating stenosis of the infraglottic space, there is no standard management approach. Currently, there are two main treatment methods: endoscopic interventions and open reconstructive surgery. Each method has its benefits and drawbacks. Despite the use of various techniques, the effectiveness of cicatricial laryngeal stenosis repair and decannulation in children is 63-64%, according to published data. With combined lesions of infraglottic and vocal cord parts of the larynx, especially with their cicatricial obliteration, reconstructive surgery is successful only in 50% of cases. Thus, treating children with post-intubation respiratory stenosis remains a complex problem and is a relevant direction for further research.

[A case of subglottic cysts in monochorionic monoamniotic twins]. / Klinicheskoe nablyudenie razvitiya podskladkovykh kist u monokhorial'nykh monoamnioticheskikh bliznetsov.

The first observation in the world literature of the development of subglottic cysts in the larynx in monochorionic monoamniotic twins is presented. The girls were born prematurely at 34 weeks of gestation, from the first day of life for 7 and 8 days, respectively, were transferred to mechanical ventilation. At the fourth month of life, symptoms of laryngeal stenosis appeared and began to gradually progress, conservative therapy had no effect. The diagnosis of subglottic cysts was established on the basis of fibrolaryngoscopy; after endolaryngeal surgery, breathing returned to normal. This case demonstrates the importance of timely endoscopic examination of the respiratory tract in children with stridor.

Spirometry in laryngotracheal stenosis: a systematic review and meta-analysis.

PURPOSE: This study aimed to assess the changes in spirometry parameters or indices after relieving laryngotracheal stenosis (LTS) in adult patients. METHODS: A systematic review and meta-analysis of studies from PubMed, Scopus, Web of Science, Cochrane Library, and EBSCO databases was conducted for assessing changes in spirometry values after endoscopic balloon dilatation of LTS in adults. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Relevant data, such as changes in mean spirometry values between preoperative and postoperative interventions, and findings of receiver operating characteristic curve analyses for predicting the need for surgical intervention, were extracted. RESULTS: Ten studies including 330 patients overall met the inclusion criteria. Significant improvements were observed from preoperative to postoperative mean values of different spirometry parameters and indices. The overall mean differences in peak expiratory flow (ΔPEF), expiratory disproportion index (ΔEDI), and peak inspiratory flow (ΔPIF) were 2.26 L/s (95% CI 2.14-2.38), 27.94 s (95% CI 26.36-29.52), and 1.21 L/s (95% CI 0.95-1.47), respectively. ΔPEF and ΔPIF values increased, while ΔEDI decreased. In predicting the need for surgical intervention, EDI had the highest sensitivity (88%), and forced expiratory volume per second/forced vital capacity had the highest specificity (85%). CONCLUSION: Spirometry is a valuable tool for assessing patients with LTS. PEF, EDI, and PIF were the most commonly reported spirometry parameters that significantly improved after airway stenosis was relieved.

Characteristics of Idiopathic Subglottic Stenosis in the Elderly.

OBJECTIVE: To compare characteristics of patients ≥65 years presenting with idiopathic subglottic stenosis (iSGS) to patients diagnosed at <65 years. We hypothesize that the groups have similar comorbidities and disease courses. DATA SOURCES: Medical records of patients treated for iSGS at a tertiary care institution from January 2005-September 2022. REVIEW METHODS: Patient demographics, time from symptom onset to diagnosis, medical history and comorbidities, and treatment modalities/intervals were recorded and analyzed. Characteristics of patients ≥65 and <65 years at presentation were compared using Chi-square analysis for non-numeric values and the Mann-Whitney U-test for numeric values. RESULTS: One hundred seven patients with iSGS were identified and 16 (15%) were aged ≥65 years (mean age 72.6, 15 female) at presentation. These patients were compared to 91 patients aged <65 years (mean age = 47.6, 90 female). Patients ≥65 years had higher rates of type 2 diabetes mellitus (T2DM) (p = 0.004) and tobacco use (p = 0.004). There were no significant differences in body mass index, gastroesophageal reflux disease, hormone replacement therapy, time from symptom onset to presentation, or length of operative treatment intervals. CONCLUSION: Patients ≥65 years with iSGS have higher rates of tobacco use, suggesting that alterations in wound healing may play a role in the development of iSGS in this age group. Although rates of T2DM were higher in the elderly group, clinical significance may be limited given the overall higher rate of diabetes mellitus in the elderly population. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:3075-3079, 2023.

Congenital Malformations of the Cricoid Cartilage: Upper Airway Obstruction and Treatment Strategy.

OBJECTIVES: To review treatment and outcomes in patients with congenital cricoid cartilage malformation. METHODS: Retrospective analysis of patients with diagnosis of congenital cricoid malformation (CCM) treated in a single tertiary pediatric referral center between 1985 and 2022. Patients were grouped according to the morphology of the cricoid cartilage that was diagnosed during endoscopy. We reviewed the treatment strategy(s), decannulation rate, complications, and functional outcomes. RESULTS: Twenty-nine patients were grouped into four morphological subtypes of cricoid cartilage: 10 patients had a hypoplastic cricoid, eight had an elliptic shape, five had severe anterior thickening, and six an accentuated V-shape posterior cricoid plate. Twenty-four patients underwent surgery, and five were closely followed up without surgical treatment. Eight patients had a tracheostomy prior to surgery, and the majority had a hypoplastic cricoid. Most patients (20 out of 24) required additional procedures postoperatively to achieve an age-appropriate airway. Thirteen patients needed endoscopic dilatation(s) and granulation tissue removal; four needed more aggressive treatment, and three patients required revision open surgery. Decannulation was achieved after a median of 4.5 months in all previously tracheostomized patients. Endoscopy at the last follow-up showed an age-appropriate airway in 27 patients; 20 patients had normal oral feeding, and 11 patients had a normal voice. CONCLUSION: Endoscopy is important to diagnose CCM and most of the time patients would need only watchful waiting. In this report, surgery was required for patients who continued to remain symptomatic and had a compromised airway. The type of surgery depends on the type of cricoid malformation and the grade of stenosis. LEVEL OF EVIDENCE: 4 Laryngoscope, 133:3185-3191, 2023.

Management of balloon dilatation in cases of subglottic stenosis in children: success and failure.

PURPOSE: To assess efficacy and prognostic factors of endoscopic balloon dilatation for the treatment of subglottic stenosis in children. METHODS: A retrospective review was performed on 49 pediatric patients with subglottic stenosis treated at the Shanghai Children's Hospital between December 2017 and December 2021. Specific demographic data, type and severity of the stenosis, number of balloon dilatations and outcomes were recorded and analyzed. RESULTS: Forty-nine children (30 male, 19 female) were included in the study with a median age at diagnosis of 24 (13-36.5) months, of which 7 (14.3%) had received open laryngotracheal reconstruction previously. The degree of subglottic stenosis was grade I in six patients, grade II in 16 patients, grade III in 20 patients and grade IV in seven patients. After various numbers of balloon dilatations (1-7 times), 29 patients showed a good outcome (decannulation or prevention of tracheostomy) and the success rate in that series was 59.2%. Overall, prognosis of balloon dilatation was not dependent on pathogeny (congenital or acquired) or open surgical history(P > 0.05), but rather on the severity grade of stenosis and the number of dilatations (P < 0.05). CONCLUSIONS: Endoscopic balloon dilatation can be safe and effective in the treatment of subglottic stenosis in children, except for more serious cases (grade IV). Open surgery should be considered if no significant improvement is observed after dilatation, especially after three or more dilatations.

Can the Remote Use of a Peak Flow Meter Predict Severity of Subglottic Stenosis and Surgical Timing?

OBJECTIVE: We aimed to assess the relationship between patient-performed and patient-reported peak flow meter (PFM) measurements with pulmonary function testing (PFT) and Dyspnea Index (DI) scores as a tool for monitoring Subglottic stenosis (SGS) disease progression remotely. METHODS: Thirty-five SGS patients were prospectively enrolled. Patients were given PFMs to report serial measurements from home. DI scores and PFT were recorded at serial clinic visits. Data were analyzed to determine the correlation between PFM measurements and PFT data. Pre-operative and post-operative PFM measurements, PFT, and DI scores were analyzed for patients who underwent operative intervention. Receiver operating characteristic (ROC) curves were created for PFM measurements, PFT data, and DI scores to predict the likelihood of surgery. RESULTS: PFM measurements had a "strong" correlation with the peak expiratory flow rate (PEFR), r = 0.78. Means of PEFR, PIFR, EDI, PFM measurements, and DI scores all significantly improved after the operative intervention (p ≤ 0.05). The area under the curve for ROC curves for DI scores, PFM measurements, and EDI were highest in our cohort with values of 0.896, 0.823, and 0.806, respectively. CONCLUSION: In our SGS cohort, PFM measurements correlate strongly with PEFR measurements. PFM measurements can adequately demonstrate disease progression and predict the need for surgery in this patient population. Together, DI scores and PFM measurements may be a useful tool to remotely follow patients with SGS and inform timing of in-person assessments. LEVEL OF EVIDENCE: 2 Laryngoscope, 133:628-633, 2023.

TREATMENT OF SUBGLOTTIC STENOSIS: A SINGLE INSTITUTION EXPERIENCE.

The aim of this article is to present experiences of the Department of Otorhinolaryngology and Head and Neck Surgery, Zagreb University Hospital Center with the treatment of patients with subglottic stenosis. Subglottic stenosis is a rare congenital or acquired disorder of airway patency that is part of a wider complex of disorders known as laryngotracheal stenosis with the ultimate effect in the form of respiratory insufficiency that can be life-threatening. As an acquired condition, it is most often the result of iatrogenic damage to the larynx and trachea during invasive airway management, whether it is intubation or tracheotomy. In the case of intubation as the etiologic factor, cases of prolonged intubation were most common. Retrospective analysis of patient medical histories over a ten-year period was performed and 29 patients met the inclusion criteria. All patients were monitored for at least two years after completion of treatment. Out of a total of 29 treated patients, 20 were permanently decannulated, of which 4 have paresis of one or both vocal cords. In conclusion, there is no clear treatment protocol for patients with subglottic stenosis. The optimal modality of treatment is combined endoscopic and open surgical treatment.