Inflammatory protein expression in human subglottic stenosis tissue mirrors that in a murine model.

OBJECTIVES: We undertook to describe the genetic and protein composition of subglottic stenosis (SGS) by measuring an array of protein expression and messenger RNA levels within human SGS tissue. We also sought to compare this human array to cytokine expression from a murine model of SGS in order to confirm the effective translational nature of our animal model. METHODS: Human granulation tissue from 10 patients with early symptomatic SGS was compared to control bronchus. The expression levels of 24 different cytokines were measured by a Luminex protein assay and real-time polymerase chain reaction. RESULTS: The protein expression in human SGS mirrors that seen in murine SGS. Transforming growth factor ß1, interleukin 1ß, and matrix metalloproteinase 9 were markedly elevated in both human and mouse SGS tissues. The protein array showed a statistically significant elevation in the proinflammatory cytokines tumor necrosis factor α, interleukin 1, granulocyte macrophage colony-stimulating factor, and interferon γ. CONCLUSIONS: This is the first study, to our knowledge, to measure an array of protein expression within human SGS tissue. The expression profile suggests that symptomatic tracheal granulation tissue is mostly within the early inflammatory phase of wound healing and has only begun fibrotic and angiogenic remodeling. This study validates our murine model of SGS, and also helps to define the exact pathways of tissue injury, in the hope of leading to new treatments for this difficult condition.

Pulse steroid therapy inhibits murine subglottic granulation.

OBJECTIVE: Using a functional model of airway granulation tissue in subglottic stenosis, we investigated changes in inflammatory markers within granulation tissue in response to intraperitoneal dexamethasone injections. Changes in inflammatory markers will allow us to identify potential targets for immunological therapy. STUDY DESIGN: Institutional Animal Care and Use Committee-approved animal study. SETTING: Philadelphia Veterans Administration Medical Center animal research facility. SUBJECTS AND METHODS: Laryngotracheal complexes of donor mice underwent direct airway injury and were transplanted into subcutaneous tissue of 19 recipient mice in 2 groups: steroid treated and untreated, with sample sizes of 10 and 9, respectively. The steroid-treated arm received intraperitoneal injection of dexamethasone for 3 weeks. Laryngotracheal complexes were then harvested, and granulation formation was measured. The messenger RNA (mRNA) expression of transforming growth factor (TGF)-ß(1) and interleukin (IL)-1 was quantified. RESULTS: At 3 weeks posttransplantation, there were statistically significant differences in observable granulation formation as well as mRNA expression of TGF-ß(1) and IL-1ß in all groups within the steroid treated arm as compared with the untreated arm. CONCLUSIONS: Systemic steroids have been used to prevent formation of granulation tissue and subglottic stenosis. However, the study of the immunologic markers and the corresponding changes with steroid treatment has not been well studied in animal models. Using a previously described novel murine model, we begin to delineate inflammatory markers that can be applied for potential therapeutic targets.

Methicillin-resistant Staphylococcus aureus laryngitis: a report of two cases with different clinical presentations.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) infection has been described in multiple areas of the head and neck. Recently, otolaryngologists have recognized MRSA infection in the glottis. We describe 2 cases of MRSA laryngitis with divergent clinical presentations: acute airway obstruction and recalcitrant hoarseness. METHODS: Report of 2 cases and review of the literature. RESULTS: In the first case, a 44-year-old woman presented with near aphonia despite maximal medical therapy. Examination showed diffuse erythema and edema of the endolarynx with yellowish plaques lining the glottis and supraglottis. Complete resolution was achieved with long-term trimethoprim-sulfamethoxazole. In the second case, a 54-year-old woman presented with recent-onset hoarseness with rapid progression to respiratory distress and biphasic stridor. Endoscopy revealed exuberant granulation tissue in the glottis with a narrowed airway. Treatment required prolonged courses of antibiotics and steroids. Diagnosis in both cases was confirmed with biopsies taken during direct laryngoscopy. CONCLUSIONS: MRSA treatment is a growing part of otolaryngologic practice and should be included in the differential diagnosis of hoarseness and stridor.

Cellular adaptive inflammation mediates airway granulation in a murine model of subglottic stenosis.

OBJECTIVE: To determine the contribution of B- and T-cell-mediated inflammation in a murine airway granulation model. STUDY DESIGN: Pilot study in a modified murine model. SETTING: Philadelphia VA Medical Center Research Building. SUBJECTS AND METHODS: Laryngotracheal complexes (LTCs) from 54 donor C57BL/6 mice were harvested and divided into 3 groups: (1) uninjured, (2) mechanically injured using a wire brush, and (3) chemically injured using hydrochloric acid. One donor LTC from each group was placed in deep dorsal subcutaneous pockets of either severe combined immunodeficiency (SCID)- or C57BL-recipient mice, for a total of 3 transplanted tracheas per recipient mouse. After 3 weeks, the transplanted LTCs were harvested from both C57BL- and SCID-recipient mice. Tissues were fixed, sectioned, and stained with hematoxylin and eosin. Representative slides were reviewed by a blinded pathologist to determine the formation of granulation tissue and graded as to the degree of formation of granulation tissue. RESULTS: Despite significant granulation formation in C57BL-recipient mice, direct airway injury did not induce the formation of granulation tissue under the disrupted epithelium of airway mucosa in SCID mice 3 weeks after injury. CONCLUSION: The data indicate that the immune response that results in the formation of granulation tissue is mediated by circulating B- and/or T-cell processes rather than resident airway immune cells. Further studies focusing on cellular adaptive immune processes in response to airway injury may provide a novel treatment modality for subglottic stenosis.

Primary tracheoesophageal puncture in stapler-assisted total laryngectomy.

BACKGROUND/AIMS: The purpose of this article was to present a novel technique for primary tracheoesophageal puncture (TEP) in patients undergoing stapler-assisted laryngectomy. METHODS: A case series of 10 consecutive patients treated with stapler-assisted laryngectomy that underwent primary TEP at the time of the initial surgery was conducted. The technique involves the use of a flexible esophagoscope and a modified Seldinger technique to safely create the TEP under direct visualization without disrupting the stapler closure. This series was performed at a single academic institution. The primary outcome measured was ability of alaryngeal speech. RESULTS: A total of 10 consecutive patients had the procedure done. All patients achieved alaryngeal speech and there were no complications. CONCLUSION: This method allows for a safe and efficient TEP creation at the time of stapler-assisted laryngectomy, obviating the need for secondary procedures, either in the office or operating room.