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the systemic nature of GPA, it seems reasonable to as- sume that these patients would have more airway diffi- culty than those with idiopathic SGS. Furthermore, one would predict that patients with GPA would have a worse clinical response to surgical treatment, including a need for more procedures and more frequent failure of open procedure, although data to support this are lacking. To further clarify this, we undertook this study to compare the manifestations and surgical management for SGS in patients with airway obstruction attributed to GPA and those with iSGS. Following approval by the Oregon Health and Science Univer- sity institutional review board, a retrospective review was per- formed of medical records of patients with GPA-SGS or iSGS seen in the otolaryngology department at our institution from 2005 through 2010. To identify patients, the department bill- ing records and operative records were queried for all encoun- ters associated with a diagnosis of GPA, laryngotracheal ste- nosis, or patients who had undergone endoscopic airway dilation or open airway reconstruction. Patients were classified as hav- ing GPA if (1) they had at least 1 clinical feature, such as SGS, consistent with the disease, and they were antineutrophil cy- toplasmic antibody (ANCA) positive; (2) they had a biopsy find- ing consistent with GPA (granulomatous inflammation, vas- culitis, and/or rapidly progressive glomerular nephritis); or (3) they manifested at least 2 signs of disease (laryngotracheal in- volvement, septal perforation, sinonasal involvement, nasolac- rimal involvement, recurrent otitis media, or characteristic re- nal or pulmonary involvement). Patients were classified as having iSGS if they did not have a history of laryngotracheal trauma or tracheotomy and the airway narrowing could not be attrib- uted to another cause, such as malignant disease or a systemic autoimmune condition. Once patients were identified, all documentation, includ- ing pre-2005 encounters, was reviewed. Data were obtained on age at diagnosis, diagnostic procedures and laboratory tests, and therapeuticmanagement, including immunosuppressive therapy and surgical procedures. SGS was diagnosed and evaluated by flexible fiber-optic examination or by intraoperative direct la- ryngoscopy. Extent of laryngotracheal involvement and gross characteristics of lesions were assessed. The Myer-Cotton stag- ing system (MCS), which was originally developed as a pedi- atric SGS scale but has since been implemented in monitoring adult SGS, was used to describe the stenosis based on the per- centage relative reduction in cross-sectional area of the sub- glottis. Four grades of stenosis are described: grade 1 lesions have less than 50% obstruction, grade 2 lesions have 51% to 70% obstruction, grade 3 lesions have 71% to 99% obstruc- tion, and grade 4 lesions have no detectable lumen or com- plete stenosis. 7 Grade of stenosis was not documented in the operative record in 17 dilations. Airway dilations were per- formed with direct microlaryngoscopy using continuous ra- dial expansion balloons (Boston Scientific), Jackson laryngeal dilators, or rigid bronchoscopic dilation. When comparing rates of surgical outcome, a minimum follow-up time of 6 months after the operative date was required for inclusion. Gastro- esophageal reflux disease was diagnosed via esophagoscopy dem- onstrating esophagitis in 3 patients, pH probe testing in 5 pa- tients, and clinical improvement of reflux symptoms with proton pump inhibitor therapy in 4 patients. Descriptive statistics, t test, Fisher exact test, Mann- Whitney U test, and 2 analysis for categorical data were per- formed ( P .05 denoted significance). METHODS

Table 1. Background Information

GPA (n = 15)

Idiopathic (n = 24)

P Value

Characteristic

Sex

Female

9 6

24

.01

Male

0

Ethnicity

Hispanic

0

1

.99

White, non-Hispanic

15

23

Comorbidities GERD

4 1 6

12

.19 .99 .01

Asthma

2 0

Lifetime tracheotomy history

Age, median, y

At GPA diagnosis At SGS diagnosis

31.7

NA

36.3 45.2

.24

Abbreviations: GERD, gastroesophageal reflux disease; GPA, granulomatosis with polyangiitis; NA, not applicable; SGS, subglottic stenosis.

RESULTS

A total of 39 patients were identified for the study, 24 with iSGS and 15 with GPA-associated subglottic air- way obstruction ( Table 1 ). Aside from the absence of males in the iSGS group, no significant differences in pa- tient demographics were noted. Of note, 4 patients with GPA-SGS in our cohort (27%) were diagnosed as hav- ing GPA when younger than 20 years. At the date of last follow-up, 7 patients with GPA-SGS (47%) exhibited dis- ease involvement restricted to the head and neck while 8 (53%) had systemic involvement, including renal and/or pulmonary manifestations. The cohort was followed for 177 patient-years. The mean and median periods of fol- low-up for the GPA-SGS group were 8.2 and 9.9 years, respectively. In comparison, the mean andmedian lengths of follow-up for the iSGS group were 2.8 and 1.8 years, respectively ( P .01). Diagnosis of the 15 patients with GPA is illustrated as follows: Patients who are ANCA positive, % 93 Patients with biopsy proven diagnosis, % 47 Patients who are ANCA positive and with diagnostic biopsy, No. 7 Patients with ANCA and nondiagnostic biopsy, No. 7 Patients diagnosed by clinical features alone, No. 1 The patient diagnosed by clinical features alone was male and, as is typical with GPA, 8 had additional dis- ease involving the nose and sinuses. Furthermore, al- though his autoantibody ANCA titers were not positive, they were interpreted as having an atypical pattern. Given these considerations, his SGS was attributed to GPA rather than an idiopathic etiology. The severity and location of stenosis observed during dilationwas assessed. Patients with iSGSwere found to have significantly worse stenosis based onMCS grading than pa- tients with GPA-SGS ( Table 2 ). There were no signifi- cant differences in the location of stenosis seen at initial dilation, although there was a trend toward more circum- ferential stenoses in the patients with GPA ( Table 3 ).

JAMA OTOLARYNGOL HEAD NECK SURG/VOL 139 (NO. 1), JAN 2013 WWW.JAMAOTO.COM

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