Localized delivery of therapeutics impact laryngeal mechanics, local inflammatory response, and respiratory microbiome following upper airway intubation injury in swine.

BACKGROUND: Laryngeal injury associated with traumatic or prolonged intubation may lead to voice, swallow, and airway complications. The interplay between inflammation and microbial population shifts induced by intubation may relate to clinical outcomes. The objective of this study was to investigate laryngeal mechanics, tissue inflammatory response, and local microbiome changes with laryngotracheal injury and localized delivery of therapeutics via drug-eluting endotracheal tube. METHODS: A simulated traumatic intubation injury was created in Yorkshire crossbreed swine under direct laryngoscopy. Endotracheal tubes electrospun with roxadustat or valacyclovir- loaded polycaprolactone (PCL) fibers were placed in the injured airway for 3, 7, or 14 days (n = 3 per group/time and ETT type). Vocal fold stiffness was then evaluated with normal indentation and laryngeal tissue sections were histologically examined. Immunohistochemistry and inflammatory marker profiling were conducted to evaluate the inflammatory response associated with injury and ETT placement. Additionally, ETT biofilm formation was visualized using scanning electron microscopy and micro-computed tomography, while changes in the airway microbiome were profiled through 16S rRNA sequencing. RESULTS: Laryngeal tissue with roxadustat ETT placement had increasing localized stiffness outcomes over time and histological assessment indicated minimal epithelial ulceration and fibrosis, while inflammation remained severe across all timepoints. In contrast, vocal fold tissue with valacyclovir ETT placement showed no significant changes in stiffness over time; histological analysis presented a reduction in epithelial ulceration and inflammation scores along with increased fibrosis observed at 14 days. Immunohistochemistry revealed a decline in M1 and M2 macrophage markers over time for both ETT types. Among the cytokines, IL-8 levels differed significantly between the roxadustat and valacyclovir ETT groups, while no other cytokines showed statistically significant differences. Additionally, increased biofilm formation was observed in the coated ETTs with notable alterations in microbiota distinctive to each ETT type and across time. CONCLUSION: The injured and intubated airway resulted in increased laryngeal stiffness. Local inflammation and the type of therapeutic administered impacted the bacterial composition within the upper respiratory microbiome, which in turn mediated local tissue healing and recovery.

Age and sex-related variations in murine laryngeal microbiota.

The larynx undergoes significant age and sex-related changes in structure and function across the lifespan. Emerging evidence suggests that laryngeal microbiota influences immunological processes. Thus, there is a critical need to delineate microbial mechanisms that may underlie laryngeal physiological and immunological changes. As a first step, the present study explored potential age and sex-related changes in the laryngeal microbiota across the lifespan in a murine model. We compared laryngeal microbial profiles of mice across the lifespan (adolescents, young adults, older adults and elderly) to determine age and sex-related microbial variation on 16s rRNA gene sequencing. Measures of alpha diversity and beta diversity were obtained, along with differentially abundant taxa across age groups and biological sexes. There was relative stability of the laryngeal microbiota within each age group and no significant bacterial compositional shift in the laryngeal microbiome across the lifespan. There was an abundance of short-chain fatty acid producing bacteria in the adolescent group, unique to the laryngeal microbiota; taxonomic changes in the elderly resembled that of the aged gut microbiome. There were no significant changes in the laryngeal microbiota relating to biological sex. This is the first study to report age and sex-related variation in laryngeal microbiota. This data lays the groundwork for defining how age-related microbial mechanisms may govern laryngeal health and disease. Bacterial compositional changes, as a result of environmental or systemic stimuli, may not only be indicative of laryngeal-specific metabolic and immunoregulatory processes, but may precede structural and functional age-related changes in laryngeal physiology.

Periodontopathogenic bacteria in subglottic samples from patients undergoing elective intubation for general anesthesia: A pilot study.

BACKGROUND: Translocation of periodontal pathogens into the respiratory tract could either cause pneumonia or disrupt local defense mechanisms, predisposing the host to infection by respiratory pathogens. The objective of this pilot study was to evaluate the levels of periodontopathogenic bacteria in subglottic samples of intubated and mechanically ventilated patients and the impact of oral decontamination with chlorhexidine (CHX) on subglottic levels of these microorganisms. METHODS: Patients scheduled to undergo elective surgical procedures requiring endotracheal intubation and mechanical ventilation for at least 3 hours were included. Following full-mouth periodontal examination, patients were randomly assigned to groups that rinsed preoperatively with 0.12% CHX or 0.9% saline (control). After 3 hours of orotracheal intubation, subglottic contents were collected. Quantification of Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis (P. gingivalis), and Tannerella forsythia (T. forsythia) in subglottic samples was determined using quantitative real-time polymerase chain reaction. Data were analyzed by Fisher Exact Probability, unpaired Student's t and Mann-Whitney tests. RESULTS: Of the 69 patients included, 43 completed study participation. There were no differences between control and CHX groups in subglottic detection rates and abundance levels of P. gingivalis (P = 0.59), T. forsythia (P = 0.83) and A. actinomycetemcomitans (P = 0.07). Moreover, our data indicate that periodontal health has no impact on subglottic levels of P. gingivalis, T. forsythia, and A. actinomycetemcomitans. CONCLUSIONS: Periodontal pathogens were detected in subglottic samples of intubated and mechanically ventilated patients. Moreover, a single CHX rinse prior to endotracheal intubation may have no effect on subglottic contamination by P. gingivalis, T. forsythia, and A. actinomycetemcomitans.

Helicobacter pylori gastric infection in patients with laryngeal cancer and chronic laryngitis.

BACKGROUND: The purpose of this study was to investigate the pathohistological status of mucous lining infected with Helicobacte pylori as the possible cause of chronic laryngitis and laryngeal carcinoma. MATERIALS AND METHODS: The prospective examination included 51 patients suffering from planocellular laryngeal cancer and 26 examinees suffering from chronic laryngitis. The examinees and the control group were subjected to esophagogastroduodenoscopy which described the local status of the esophagus and stomach. Two biopsy samplings are taken from the stomach antrum and corpus. One part of the biopsies was colored using the histological technique used in the pathohistological detection of H. pylori, while the other part was incorporated in paraffin cubes where the H. Pylori gene expression was determined using the deparaffinization and PCR method DNA isolation. RESULTS: In the group of examinees suffering from laryngeal tumor, there were a higher number of patients suffering also from chronic gastritis (32/51) than in the other group, suffering from chronic laryngitis (9/26). In the chronic laryngitis group, there were more examinees with acute gastritis (12/26) than in the examined group (11/51). The difference is statistically significant (p = 0.0457). CONCLUSION: Chronic gastritis and H. pylori infection are risk factors for laryngeal carcinoma formation; therefore, acute gastritis with helicobacter pylori infection must be immediately treated to not let infection to become chronic.

Leukoplakia or LPR: The Misdiagnosis of Laryngeal Tuberculosis.

OBJECTIVE: The objective is to reduce the rates of misdiagnosis and inappropriate treatment of laryngeal tuberculosis (LTB). STUDY DESIGN: Retrospective case series. MATERIALS AND METHODS: Medical records of 3 histopathology-confirmed cases at a tertiary medical center from 2000 to 2018. RESULTS: Seventeen patients with LTB included in this study. Of the 17 patients, 16 patients were male and 1 was female; 11 patients had a history of smoking. Odynophagia was the chief complaint in 6 cases, and 11 patients complained of hoarseness. The appearance of the affected larynx was ranged from diffuse swelling (n = 7, 41.2%), mucosa white lesion (n = 5,29.4%), and granulomatous tumors (n = 2, 11.76%), and these features presented together (n = 2, 11.76%). Seventeen patients with LTB were misdiagnosed as acute epiglottitis in 4 (23.5%) patients, acute laryngitis in 1 (5.9%) patient, leukoplakia in 5 (29.4%) patients, laryngopharyngeal reflux (LPR) in 6 (35.3%) patients, and laryngocarcinoma in 1 (5.9%) patient. Chest computed tomography reported old pulmonary tuberculosis in 2 (11.7%) patients, active pulmonary tuberculosis in 7 (41.2%) patients, and normal lung status in 8 (47.1%) patients. Histopathological examination reported Mycobacterium tuberculosis infection by revealing epithelioid cell granulomas with Langhans-type giant cells in 14 (82.4%) patients and epithelioid cell granulomas with caseous necrosis and Langhans-type giant cells in 3 (17.6%) patients. CONCLUSIONS: Laryngeal tuberculosis was easily misdiagnosed as acute epiglottitis or leukoplakia because of diffuse swelling of the epiglottis or white lesions over the true vocal cord, especially patients with increasing LTB were misdiagnosed as LPR with the enhancement of LPR awareness among otolaryngologist. Clinicians should be aware of the possibility of LTB for chronic intractable laryngitis with failure treatment of proton pump inhibitor and recurrent acute epiglottitis with foreign body injury.

Laryngeal chondritis as a differential for upper airway diseases in German sheep.

BACKGROUND: Ovine laryngeal chondritis is a rare entity of sheep in the USA, Great Britain, New Zealand and Iceland, but has not been reported in Germany so far. Here, two German cases are reported. CASE PRESENTATION: Two rams showed severe and progressive signs of dyspnea. Endoscopically, a severe bilateral swelling of the larynx was identified in both rams. Due to poor prognosis and progression of clinical signs one ram was euthanized, while the other ram died overnight. In both cases, a necrosuppurative laryngitis and chondritis of arytenoid cartilages was found at necropsy. Fusobacterium necrophorum and Streptococcus ovis were isolated from the laryngeal lesion in one animal. CONCLUSIONS: This is the first report of ovine laryngeal chondritis in continental Europe. This entity should be considered a differential diagnosis for upper airway disease in sheep.

Detection of Mycoplasma hyopneumoniae in nasal and laryngeal swab specimens in endemically infected pig herds.

BACKGROUND: Apparently, laryngeal swabs (LS) are more sensitive than nasal swabs (NS) and allow earlier detection of Mycoplasma hyopneumoniae by PCR. However, antecedents about the compared detection of M hyopneumoniae with NS and LS in growing pigs, from naturally infected herds, are lacking in the literature. Thus, this study compared the PCR detection of M hyopneumoniae from NS and LS in pigs of various ages. METHODS: A longitudinal study was performed at two farms where NS and LS were collected from three consecutive groups of 20 pigs at 3, 6, 10, 16 and 22 weeks of age. All samples were analysed by nested PCR for M hyopneumoniae detection. RESULTS: The probability of PCR detection of M hyopneumoniae was higher in LS for pigs of all ages (odds ratio (OR)=1.87; 95 per cent confidence interval (CI) 1.31-2.67) and in 22-week-old pigs (OR=4.87; 95 per cent CI 2.86-8.30). The agreement between both sample types was low to moderate (kappa 0.087-0.508), highlighting that M hyopneumoniae does not appear to colonise the respiratory tract in a generalised and consistent fashion. CONCLUSIONS: The results suggest that LS could be employed at different ages to achieve greater bacterial detection. Considering that LS is a minimally invasive, highly sensitive sample compared with the traditional NS, it could be suggested to employ this sample type for M hyopneumoniae detection in naturally infected pigs.

Comparison of the sensitivity of laryngeal swabs and deep tracheal catheters for detection of Mycoplasma hyopneumoniae in experimentally and naturally infected pigs early and late after infection.

Detection of Mycoplasma hyopneumoniae infection in live pigs is a critical component to measure the success of disease control or elimination strategies. However, in vivo diagnosis of M. hyopneumoniae is difficult and the imperfect sensitivity of diagnostic tools has been deemed as one of the main challenges. Here, the sensitivity of laryngeal swabs and deep tracheal catheters for detection of M. hyopneumoniae early and late after infection was determined using inoculation status as a gold standard in experimentally infected pigs and a Bayesian approach in naturally infected pigs. Three-hundred and twenty 8-week old seeder pigs were intra-tracheally inoculated with M. hyopneumoniae strain 232 and immediately placed with 1920 contact pigs to achieve a 1:6 seeder-to-contact ratio. A subset of seeders and contacts were longitudinally sampled at 7, 28, 97, and 113 days post-inoculation (dpi) and at 28, 56, 84, and 113 days post-exposure (dpe), respectively, using laryngeal swabs and deep tracheal catheters. Samples were tested for M. hyopneumoniae by a species-specific real-time PCR. The sensitivity of deep tracheal catheters was higher than the one obtained in laryngeal swabs at all samplings (seeders: 36% higher than laryngeal swabs at 7 dpi, 29% higher at 97 dpi, and 44% higher at 113 dpi; contacts: 51% higher at 56 dpe, 42% higher at 84 dpe, and 32% higher at 113 dpe). Our study indicates that deep tracheal catheters were a more sensitive sample than laryngeal swabs. The sensitivity of both sample types varied over time and by exposure method, and these factors should be considered when designing diagnostic strategies.

Primary Laryngeal Blastomycosis: Diagnostic Challenges and Advances in a Rare Cause of Laryngitis.

Blastomyces dermatitidis is a fungal organism endemic to the central and southern United States and capable of causing numerous diseases. Primary blastomycosis of the larynx is a rare clinical entity with a limited number of reported cases in the literature. Diagnosis is challenging as a result of nonspecific physical exam findings, difficulty of histopathologic detection and culture, and need for operative laryngeal biopsy for definitive identification. Molecular and serologic testing is not widely available. The authors present a case of laryngeal blastomycosis, the diagnosis of which was facilitated by in-office biopsy, and discuss diagnostic challenges. Laryngoscope, 129:2531-2533, 2019.

Laryngeal histoplasmosis in a kidney transplant recipient.

Histoplasma capsulatum is an endemic fungus that most oftenly causes a self-limiting illness but can result in severe infections in immunocompromised patients including pulmonary or extra-pulmonary disease. Rarely it can also cause a chronic progressive infection of the larynx. Herein, we report a case of laryngeal histoplasmosis in a kidney transplant patient who presented with progressive symptoms of several weeks of hoarseness, dysphagia and odynophagia. Laryngoscopic examination revealed thick plaques in the oropharynx with surrounding hyper-erythema and histopathology showed numerous intracellular yeasts forms consistent with H capsulatum. Patient was initiated on treatment with itraconazole. Infection of the larynx due to H capsulatum is highly uncommon and therefore can result in an inappropriate or delayed diagnosis. A review of literature showed four previously reported cases of laryngeal histoplasmosis in patients with solid organ transplant. This is the first case series of laryngeal histoplasmosis in transplant recipients.

Aspergillus infection of the larynx in a solid organ transplant recipient.

Primary laryngeal aspergillosis is a rare condition. Only a few cases have been reported in the past years. Most of them have been reported in healthy patients or with a mild immunocompromised state. We report a case of primary laryngeal aspergillosis in a solid organ transplant recipient (SOT), an infection not previously described in this population; we reviewed the published literature in all populations.

Possible association between Helicobacter pylori infection and vocal fold leukoplakia.

BACKGROUND: Several studies have indicated the larynx as possible Helicobacter pylori (H. pylori) reservoirs. This study explored the association between H. pylori and vocal fold leukoplakia. METHODS: The case-control study involved 51 patients with vocal fold leukoplakia and 35 control patients with vocal polyps. Helicobacter pylori was detected in tissues by the rapid urease test, nested polymerase chain reaction (PCR), and single-step PCR. The H. pylori-specific immunoglobulin antibodies were detected in plasma by enzyme-linked immunosorbent assay (ELISA). RESULTS: Helicobacter pylori-positive rate of vocal fold leukoplakia and vocal polyps was 23.5% versus 11.4% (P = .157), 37.2% versus 14.3% (P = .020), 27.5% versus 8.6% (P = .031), and 70.6% versus 68.6% (P = .841) detected by rapid urease test, nested PCR, single-step PCR, and ELISA, respectively. Regression analysis indicated that H. pylori infection (P = .044) was the independent risk factor for vocal fold leukoplakia. CONCLUSION: Helicobacter pylori infection exists in the larynx and may be associated with vocal fold leukoplakia.

Does gene expression in laryngeal subsites differ between patients with laryngopharyngeal reflux and controls?

OBJECTIVE: To identify laryngeal mRNA gene changes in patients with laryngopharyngeal reflux (LPR). METHOD: Laryngeal biopsies from non-smoking LPR patients (n=10; Reflux Symptom Index (RSI) >12 and a Reflux Finding Score (RFS) >6) and controls (n=9; RSI <12 and RFS <6) were collected from four subsites (true vocal cord, false vocal cord, medial arytenoid and posterior commissure) of the larynx. qRT-PCR analyses were conducted on 20 reflux- and inflammation-related genes, including interleukins 6 and 8, cytokeratins 8 and 14, mucin genes MUC1, MUC2, MUC3B, MUC4, MUC5B, MUC6 and MUC7 and carbonic anhydrase III. Statistical analysis (Mann-Whitney U test) compared gene expression levels between LPR and control groups at each subsite. RESULTS: Site-specific differences in squamous metaplasia and gene expression were noted in LPR patients, with the majority present in the medial arytenoid region. Significant.differences were noted in genes related to mucosal defence and inflammation, including CRNN, CD1d, TGFß-1, MUC2, MUC5B and CDH1. CONCLUSION: Whilst the posterior commissure is commonly identified as the area demonstrating the most significant macroscopic change in LPR, the histological changes and genes assessed here showed more pronounced LPR associated differences in the medial arytenoid. We identified differences in expression of mucin genes, cytokeratin-14 and molecular markers of inflammation. Whilst some of these changes may be metaplasia-related, further evaluation of the mRNA expression of these genes may provide a useful biomarker panel for diagnosis and therapeutic monitoring of LPR.

MRSA chronic bacterial laryngitis: A growing problem.

OBJECTIVES: Chronic bacterial infection of the larynx is characterized by long-standing hoarseness and exudative laryngitis. Prolonged antibiotic therapy is required to clear the infection, and methicillin-resistant staphylococcus aureus (MRSA) may be the responsible pathogen. The objective of this study was to describe the presentation, comorbidities, treatment response, and underlying etiology- including the incidence of MRSA-in our patient population with chronic bacterial laryngitis. METHODS: A review of patients with a diagnosis of chronic bacterial laryngitis from 2012 to 2016 was performed. Diagnosis of chronic bacterial laryngitis was based on clinical history and findings on flexible laryngoscopy. In selected cases, the diagnosis of bacterial laryngitis was confirmed by operative biopsy. Information regarding clinical presentation and course was collected. RESULTS: Twenty-eight patients were included in the study. Twenty-three were treated empirically with Amoxicillin-clavulonic acid for a minimum of 21 days. Twelve of the 23 (52%) had recurrence or nonresolution of infection. Seven of the 12 nonresponders (58%) were found to have MRSA by laryngeal tissue culture. Five patients were treated initially with Sulfamethoxazole and trimethoprim, and all resolved the infection without the need for further treatment. There was a nonstatistically significant increase in smoking and reflux in the MRSA population compared to the non-MRSA group. CONCLUSION: MRSA infection was documented in 30% of patients overall with chronic bacterial laryngitis. Based on the results of the study, a treatment algorithm for management of this unusual patient population is suggested. LEVEL OF EVIDENCE: 4. Laryngoscope, 128:921-925, 2018.

Microbial Communities Associated with Primary and Metastatic Head and Neck Squamous Cell Carcinoma - A High Fusobacterial and Low Streptococcal Signature.

Given the potential relationship between head and neck squamous cell carcinoma (HNSCC) and microbial dysbiosis, we profiled the microbiome within healthy normal and tumorous (primary and metastatic) human tissues from the oral cavity, larynx-pharynx, and lymph nodes using 16S rRNA sequencing. Alpha and beta diversity analyses revealed that normal tissues had the greatest richness in community diversity, while the metastatic populations were most closely related to one another. Compared to the normal, the microbiota associated with tumors supported altered abundances in the phyla Fusobacteria, Firmicutes, Actinobacteria and Proteobacteria. Most notably, the relative abundance of Fusobacterium increased whereas Streptococcus decreased in both primary and metastatic samples. Principal coordinate analysis indicated a separation and clustering of samples by tissue status. However, random forest analysis revealed that the microbial profiles alone were a poor predictor for primary and metastatic HNSCC samples. Here, we report that the microbial communities residing in the tumorous tissues are compositionally distinct compared to the normal adjacent tissues. However, likely due to the smaller sample size and sample-to-sample heterogeneity, our prediction models were not able to distinguish by sample types. This work provides a foundation for future studies aimed at understanding the role of the dysbiotic tissue microbiome in HNSCC.