Review article: reflux and its consequences--the laryngeal, pulmonary and oesophageal manifestations. Conference held in conjunction with the 9th International Symposium on Human Pepsin (ISHP) Kingston-upon-Hull, UK, 21-23 April 2010

Bile salt-enriched vs. non-enriched nanoparticles: comparison of their physicochemical characteristics and release pattern

Bile salts were first used in the preparation of nanoparticles due to their stabilizing effects. As time went by, they attracted much attention and were increasingly employed in fabricating nanoparticles. It is well accepted that the physicochemical properties of nanoparticles are influential factors in their permeation, distribution, elimination and degree of effectiveness as well as toxicity. The review of articles shows that the use of bile salts in the structure of nanocarriers may cause significant changes in their physicochemical properties. Hence, having information about the effect of bile salts on the properties of nanoparticles could be valuable in the design of optimal carriers. Herein, we review studies in which bile salts were used in preparing liposomes, niosomes and other nanocarriers. Furthermore, the effects of bile salts on entrapment efficiency, particle size, polydispersity index, zeta potential, release profile and stability of nanoparticles are pointed out. Finally, we debate how to take advantage of bile salts potential for preparing desirable nanocarriers.

Usefulness of pepsin saliva measurement for the detection of primary burning mouth syndrome related to reflux

OBJECTIVES

To study the diagnostic value of salivary pepsin tests for detecting laryngopharyngeal reflux (LPR) in patients with primary burning mouth syndrome (BMS).

METHODS

Patients with BMS and asymptomatic individuals were consecutively recruited from September 2018 to June 2023. Patients underwent hypopharyngeal-esophageal impedance pH-monitoring (HEMII-pH) and saliva collections to measure pepsin. Stomatology evaluation was carried out to exclude other causes of BMS. Oral, pharyngeal and laryngeal signs and symptoms were evaluated with Reflux Sign Assessment (RSA) and Reflux Symptom Score (RSS). Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values of pepsin test were calculated considering the highest values of pepsin tests at ≥ 16, ≥ 36, and ≥ 100 ng/mL cutoffs. Receiver operating characteristic curve (ROC) was evaluated.

RESULTS

Forty-nine patients with both BMS and LPR at the HEMII-pH and 21 asymptomatic individuals were recruited. Pepsin test was 83.7%, 79.6%, and 71.4% sensitive at cutoffs ≥ 16, ≥ 36, and ≥ 100 ng/mL, respectively. The ROC analysis reported that a threshold of ≥ 21.5 ng/mL was associated with sensitivity, specificity, PPV and NPV of 81.6%, 81.0%, 90.1% and 65.4%, respectively. The severity score of burning mouth symptom was significantly associated with the saliva pepsin concentration (rs = 0.263; p = 0.029) and the oral RSA (rs = 0.474; p = 0.007).

CONCLUSION

Pepsin test is a valuable diagnostic approach for detecting LPR in patients with BMS. Patients with high level of saliva pepsin reported more severe burning mouth symptoms. Future studies are needed to confirm the role of LPR in the primary BMS.

Alginates for Protection Against Pepsin-Acid Induced Aerodigestive Epithelial Barrier Disruption

OBJECTIVE

Gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) are chronic conditions caused by backflow of gastric and duodenal contents into the esophagus and proximal aerodigestive tract, respectively. Mucosal barrier dysfunction resultant from the synergistic actions of chemical injury and the mucosal inflammatory response during reflux contributes to symptom perception. Alginates effectively treat symptoms of mild to moderate GERD and have recently shown benefit for LPR. In addition to forming a "raft" over gastric contents to reduce acidic reflux episodes, alginates have been found to bind the esophageal mucosa thereby preserving functional barrier integrity measured by transepithelial electrical resistance. The aim of this study was to further examine the topical protective capacity of alginate-based Gaviscon Advance (GA) and Double Action (GDA) against pepsin-acid mediated aerodigestive epithelial barrier dysfunction in vitro.

STUDY DESIGN

Translational.

METHODS

Immortalized human esophageal and vocal cord epithelial cells cultured in transwells were pretreated with liquid formula GA, GDA, matched viscous placebo solution, or saline (control), then treated for 1 h with saline, acid (pH 3-6) or pepsin (0.1-1 mg/ml) at pH 3-6. Endpoint measure was taken of horseradish peroxidase (HRP) allowed to diffuse across monolayers for 2 h.

RESULTS

Pepsin (0.1-1 mg/ml) at pH 3-6 increased HRP flux through cultures pretreated with saline or placebo (p < 0.05); acid alone did not. GA and GDA prevented barrier dysfunction.

CONCLUSIONS

GA and GDA preserved epithelial barrier function during pepsin-acid insult better than placebo suggesting that protection was due to alginate. These data support topical protection as a therapeutic approach to GERD and LPR. Laryngoscope, 132:2327-2334, 2022.

The role of Glut-1 and H+/K+-ATPase expression in hyperplasia of mice laryngeal epithelium induced by pepsin

Purpose

To explore the role played by Glut-1 and H⁺/K⁺-ATPase in pepsin-induced, mouse laryngeal epithelial proliferation, growth, and development.

Methods

We established a mouse model of laryngopharyngeal reflux and measured Glut-1 and H⁺/K⁺-ATPase expression levels in mouse laryngeal epithelium treated with artificial gastric juice containing pepsin.

Results

Artificial pepsin-containing gastric juice induced significant hyperplastic changes in mouse laryngeal epithelium compared to control mice at 15, 30, and 45 days. Inhibition of Glut-1 expression by 2-DG significantly suppressed such hyperplasia compared to mice exposed to artificial gastric juice containing pepsin at 15, 30, and 45 days. After treatment with pepsin-containing artificial gastric juice, RT-PCR and Western blotting showed that the levels of Glut-1 and H⁺/K⁺-ATPase α, β increased significantly.

Conclusions

Pepsin-containing artificial gastric juice promoted mouse laryngeal epithelial hyperplasia associated with abnormal expression of Glut-1 and H⁺/K⁺-ATPase α, β.

Role and mechanism of Glut-1 and H+/K+-ATPase expression in pepsin-induced development of vocal cord leukoplakia

PURPOSE

We investigated the role of Glut-1 and H⁺/K⁺-ATPase expression in pepsin-induced development of human vocal cord leukoplakia cells (HVCLCs). Next, we analyzed the relationship between Glut-1 and H⁺/K⁺-ATPase expression with the clinicopathological features of laryngeal carcinoma.

METHODS

Glut-1 and H⁺/K⁺-ATPase expression levels in HVCLCs were determined after treatment with artificial gastric juice containing pepsin and laryngeal carcinoma tissues.

RESULTS

Exposure to pepsin-containing artificial gastric juice significantly enhanced the migration and proliferation of VSCLCs in a time-dependent manner. The apoptotic rate of VSCLCs decreased over time after exposure to pepsin and reached a nadir on day 7 (p < 0.01). With increasing duration of exposure to pepsin, the proportion of VSCLCs in G0/G1 phase decreased and the proportions in the S and G2/M phases significantly increased (p < 0.05). After treatment with pepsin-containing artificial gastric juice, RT-PCR and Western blotting showed that the expression of Glut-1 and H⁺/K⁺-ATPase α, β significantly increased in HVCLCs compared to in the absence of pepsin (p < 0.05). The expression of Glut-1 and H⁺/K⁺-ATPase α, β gradually increased from vocal cord leukoplakia (VLC) to laryngeal carcinoma (p < 0.05). Lentivirus-mediated inhibition of Glut-1 expression in VCL significantly inhibited the cells' migration and proliferation (p < 0.05) but enhanced their apoptosis (p < 0.05). Also, inhibition of Glut-1 expression resulted in an increased proportion of cells in G0/G1 phase and a significantly decreased proportion in G2/M phase (p < 0.05).

CONCLUSIONS

Elevated Glut-1 expression may promote the development of VCL by upregulating laryngeal H⁺/K⁺-ATPase expression to reactivate absorbed pepsin, thus damaging the laryngeal mucosa.

How I Approach Laryngopharyngoesophageal Reflux (LPR)

The purpose of this article is to review the cornerstone and most recent literature regarding laryngopharynoesophageal reflux (LPR) including epidemiological characteristics, pathophysiology, symptoms, diagnosis, and management. The role of pepsin in the pathophysiology of LPR is highlighted in addition to new diagnostic modalities and pharmacologic therapies that target pepsin.

Refractory Gastroesophageal Reflux Disease: A Management Update

Gastroesophageal reflux disease (GERD) is one of the most frequent gastrointestinal disorders. Proton pump inhibitors (PPIs) are effective in healing lesions and improving symptoms in most cases, although up to 40% of GERD patients do not respond adequately to PPI therapy. Refractory GERD (rGERD) is one of the most challenging problems, given its impact on the quality of life and consumption of health care resources. The definition of rGERD is a controversial topic as it has not been unequivocally established. Indeed, some patients unresponsive to PPIs who experience symptoms potentially related to GERD may not have GERD; in this case the definition could be replaced with “reflux-like PPI-refractory symptoms.” Patients with persistent reflux-like symptoms should undergo a diagnostic workup aimed at finding objective evidence of GERD through endoscopic and pH-impedance investigations. The management strategies regarding rGERD, apart from a careful check of patient's compliance with PPIs, a possible change in the timing of their administration and the choice of a PPI with a different metabolic pathway, include other pharmacologic treatments. These include histamine-2 receptor antagonists (H2RAs), alginates, antacids and mucosal protective agents, potassium competitive acid blockers (PCABs), prokinetics, gamma aminobutyric acid-B (GABA-B) receptor agonists and metabotropic glutamate receptor-5 (mGluR5) antagonists, and pain modulators. If there is no benefit from medical therapy, but there is objective evidence of GERD, invasive antireflux options should be evaluated after having carefully explained the risks and benefits to the patient. The most widely performed invasive antireflux option remains laparoscopic antireflux surgery (LARS), even if other, less invasive, interventions have been suggested in the last few decades, including endoscopic transoral incisionless fundoplication (TIF), magnetic sphincter augmentation (LINX) or radiofrequency therapy (Stretta). Due to the different mechanisms underlying rGERD, the most effective strategy can vary, and it should be tailored to each patient. The aim of this paper is to review the different management options available to successfully deal with rGERD.

Using RSI and RFS scores to differentiate between reflux-related and other causes of chronic laryngitis

OBJECTIVE

To establish if the Reflux Symptom Index (RFI) and the Reflux Finding Score (RFC) can help establish the differential diagnosis in patients with distinct causes of chronic laryngopharyngitis.

METHODS

A group of 102 adult patients with chronic laryngopharyngitis (Group A - 37 patients with allergic rhinitis; Group B - 22 patients with Obstructive Sleep Apnea (OSA); Group C - 43 patients with Laryngopharyngeal Reflux (LPR)) were prospectively studied. Chronic laryngitis was diagnosed based on suggestive symptoms and videolaryngoscopic signs (RSI ≥ 13 and RFS ≥ 7). Allergies were confirmed by a positive serum RAST, OSA was diagnosed with a positive polysomnography, and LPR with a positive impedance-PH study. Discriminant function analysis was used to determine if the combination of RSI and RFS scores could differentiate between groups.

RESULTS

Patients with respiratory allergies and those with LPR showed similar and significantly higher RSI scores when compared to that of patients with OSA (p < 0.001); Patients with OSA and those with LPR showed similar and significantly higher RFS scores when compared to that of patients with Respiratory Allergies (OSA vs. Allergies p < 0.001; LPR vs. Allergies p < 0.002). The combination of both scores held a higher probability of diagnosing OSA (72.73%) and Allergies (64.86%) than diagnosing LPR (51.16%).

CONCLUSIONS

RSI and RFS are not specific for reflux laryngitis and are more likely to induce a false diagnosis if not used with diligence.

Impaired Proximal Esophageal Contractility Predicts Pharyngeal Reflux in Patients With Laryngopharyngeal Reflux Symptoms

OBJECTIVES

The pathophysiology of laryngopharyngeal reflux (LPR) remains incompletely understood. Proximal esophageal motor dysfunction may impair bolus clearance, increasing the risk of pharyngeal refluxate exposure. We aimed to evaluate the association of proximal esophageal contractility with objective reflux metrics.

METHODS

We evaluated adults with LPR symptoms undergoing high-resolution manometry (HRM) and combined hypopharyngeal-esophageal multichannel intraluminal impedance-pH testing at a tertiary center between March 2018 and August 2019. Routine parameters per Chicago classification were obtained on HRM. Proximal esophageal contractility was evaluated using proximal contractile integral (PCI), which quantifies contractile pressure >20 mm Hg for the region spanning the distal margin of the upper esophageal sphincter and transition zone. Univariate (Kendall correlation and Student t test) and multivariable (general linear regression and logistic regression) analyses were performed.

RESULTS

We enrolled 138 patients (66.7% women, mean age 57.1 years) in this study. Lower PCI was associated with an elevated risk of increased pharyngeal reflux (adjusted odds ratio 0.83 per 100 mm Hg-s-cm change in PCI, 95% confidence interval: 0.69-0.98), with a trend toward increased bolus exposure time and total reflux events, after multivariable adjustment. The relationship between PCI and pharyngeal reflux was strongest among participants without a primary motility disorder on HRM (adjusted odds ratio 0.63, 95% confidence interval: 0.42-0.85, P interaction = 0.04). Among continuously expressed reflux parameters, lower PCI was significantly associated with more distal acid reflux events (β = -0.0094, P = 0.03) and total reflux events (β = -0.0172, P = 0.05), after adjusting for confounders.

DISCUSSION

Reduced proximal esophageal contractility as assessed by decreased PCI on HRM independently predicted increased pharyngeal reflux in patients with LPR symptoms, particularly among those without a coexisting motility disorder.

Atypical Clinical Presentation of Laryngopharyngeal Reflux: A 5-Year Case Series

Background: Laryngopharyngeal reflux (LPR) is a common disease in otolaryngology characterized by an inflammatory reaction of the mucosa of the upper aerodigestive tract caused by digestive refluxate enzymes. LPR has been identified as the etiological or favoring factor of laryngeal, oral, sinonasal, or otological diseases. In this case series, we reported the atypical clinical presentation of LPR in patients presenting in our clinic with reflux. Methods: A retrospective medical chart review of 351 patients with LPR treated in the European Reflux Clinic in Brussels, Poitiers and Paris was performed. In order to be included, patients had to report an atypical clinical presentation of LPR, consisting of symptoms or findings that are not described in the reflux symptom score and reflux sign assessment. The LPR diagnosis was confirmed with a 24 h hypopharyngeal-esophageal impedance pH study, and patients were treated with a combination of diet, proton pump inhibitors, and alginates. The atypical symptoms or findings had to be resolved from pre- to posttreatment. Results: From 2017 to 2021, 21 patients with atypical LPR were treated in our center. The clinical presentation consisted of recurrent aphthosis or burning mouth (N = 9), recurrent burps and abdominal disorders (N = 2), posterior nasal obstruction (N = 2), recurrent acute suppurative otitis media (N = 2), severe vocal fold dysplasia (N = 2), and recurrent acute rhinopharyngitis (N = 1), tearing (N = 1), aspirations (N = 1), or tracheobronchitis (N = 1). Abnormal upper aerodigestive tract reflux events were identified in all of these patients. Atypical clinical findings resolved and did not recur after an adequate antireflux treatment. Conclusion: LPR may present with various clinical presentations, including mouth, eye, tracheobronchial, nasal, or laryngeal findings, which may all regress with adequate treatment. Future studies are needed to better specify the relationship between LPR and these atypical findings through analyses identifying gastroduodenal enzymes in the inflamed tissue.

Association between gastroesophageal reflux disease and vocal fold polyps

The aim of this study is to explore the relationship between gastroesophageal reflux disease (GERD) and vocal fold polyps (VFPs).This is a Case-Control study and was performed with the help of The Second Affiliated Hospital of Chongqing Medical University.Twenty-seven patients with VFP and 20 controls without VFP were recruited between May and October 2018. All the subjects underwent a saliva pepsin test, completed the GerdQ questionnaire and 24-hour multichannel intraluminal impedance with pH (24-h MII-pH) monitoring. Twenty-five resected VFP specimens were examined with immunohistochemical (IHC) and double immunofluorescence (IF) staining.The incidence of GERD in the VFP group was significantly higher than that in the control group (P = .003). Patients with VFP had significantly higher GerdQ scores, pepsin concentrations, and pepsin-positive rates (P < .05). Moreover, the number of proximal and upright reflux events was significantly higher in the VFP group (P < .05). The pepsin concentration in saliva showed a significant positive correlation with the pepsin levels in tissues (r2 = 0.50, P = .011). Pepsin and TGF-β1-positive cells were colocalized with CD45RO-positive cells. IHC staining showed that the majority of VFP patients had a positive expression of pepsin (20/25, 80%) and pepsin-positive cells were found in both the squamous epithelium and mesenchymal tissues. IHC staining of TGF-β1 in VFP revealed findings similar to those of pepsin staining.GERD is an important risk factor for VFP. Pepsin may promote the aggregation of immune cells, increase the local cytokines, and promote inflammatory reaction, suggesting a potential new pathogenesis for VFP. The saliva pepsin test is a reliable method for GERD diagnosis.

Irritant-Induced Chronic Cough Triggers: A Scoping Review and Clinical Checklist

Purpose The primary aim of this review was to identify environmental irritants known to trigger chronic cough through the life span and develop a comprehensive clinically useful irritant checklist. Method A scoping review was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis Extension for Scoping Reviews, checklist, and explanation. English-language, full-text resources were identified through Medline, PsycINFO, SPORTDiscus, Web of Science, and ProQuest Dissertations and Theses Global. Results A total of 1,072 sources were retrieved; of these, 109 were duplicates. Titles of abstracts of 963 articles were screened, with 295 selected for full-text review. Using the exclusion and inclusion criteria listed, 236 articles were considered eligible and 214 different triggers were identified. Triggers were identified from North America, Europe, Africa, Asia, and Australia. Occupational exposures were also delineated. Conclusions A clinically useful checklist of both frequently encountered triggers and idiosyncratic or rare triggers was developed. The clinical checklist provides a unique contribution to streamline and standardize clinical assessment of irritant-induced chronic cough. The international scope of this review extends the usefulness of the clinical checklist to clinicians on most continents.

[Phytotherapeutische Ansätze zur Behandlung des laryngopharyngealen Reflux in der HNO-Praxis]

Der gastroösophageale Reflux, auch GERD genannt (gastroesophageal reflux disease) ist mit einer Prävalenz von 20-30% der erwachsenen Bevölkerung ein weit verbreitetes Problem. Davon abzugrenzen ist der häufig in der HNO-Praxis anzutref-fende laryngopharyngeale Reflux (LPR), bei dem es sich um eine durch den Magensäurereflux bedingte Entzündung der oberen Atemwege handelt. Die Unterschiede im klinischen Bild charakterisieren die widersprüchliche Beziehung der beiden klinischen Entitäten und erschweren die Diagnosestellung. Darüber hinaus muss ein besonderes Augenmerk auf Beschwerden des Magen- und Darmtrakts gelegt und deren Behandlung nicht vernachlässigt werden. Neben diätetischen Ratschlägen zählen einige pflanzliche Arzneimittel zu den Therapieoptionen. Alginate, die ein Aufstossen verhindern, bewähren sich in der Praxis. Kombinationsarzneimittel aus der europäischen und tibetischen Tradition spielen eine wesentliche Rolle in der Behandlung, nicht nur des LPR sondern auch bei Verdauungsproblemen des oberen und unteren Verdauungstrakts, wie Reizmagen und Reizdarm.

The gastroesophageal reflux, also called GERD (gastroesophageal reflux disease), is a widespread problem with 20–30% of the adult population concerned. The laryngopharyngeal reflux (LPR), which is an inflammation of the upper respiratory system due to reflux of gastric acids, is a frequently encountered problem of the gastrointestinal practitioner and should be separated from GERD. The differences in the clinical image characterize the contradictory relationship of both clinical entities and complicate the diagnosis. In addition, the focus should also be turned on eventual disorders of the gastrointestinal tract and, if necessary, they should be treated, too. Besides dietetic advice some herbal medicines belong to the therapeutic options. Alginates, which prevent reflux, have proved a great value in the practice. Multicomponent mixtures originating from the European and Tibetan herbal medicine traditions play a major role in the treatment, not only for LPR, but also for the upper and lower digestive pathologies such as functional dyspepsia and irritable colon.

Impact of bile acids on the severity of laryngo-pharyngeal reflux

OBJECTIVES

The primary end point of this study was to evaluate the impact of bile acids on severity of laryngo-pharyngeal reflux (LPR) and the possible correlation with esophagitis and upper airway malignancies. The second end point was to evaluate if salivary bile acids and molecules other than pepsin might serve as diagnostic biomarkers of LPR.

DESIGN

Observational prospective comparative study.

SETTING

Otorhinolaryngology unit of a tertiary hospital.

PARTICIPANTS

Sixty-two consecutive adult outpatients suspected of LPR.

MAIN OUTCOME MEASURES

Bile acids, bilirubin and pepsinogen I-II were measured in saliva. Patients underwent pH metry and based on the results of bile acids were subdivided as acid, mixed and alkaline LPR.

RESULTS

Significantly higher Reflux Findings Score (RFS) and Reflux Symptoms Index (RSI) were seen in patients with alkaline and mixed LPR compared to acid LPR. Salivary bile acids >1 µmol/L seem to be a reliable indicator of the severity of LPR. Compared to those without, patients with esophagitis or a history of upper airway malignancy have high concentrations of bile acids in saliva. Among the molecules studied, bile acids were the most suitable for diagnosis of LPR, with a sensitivity of 86% and a positive predictive value of 80.7%.

CONCLUSIONS

Our data suggest that high concentrations of bile acids are associated with higher values of RSI and RFS in LPR as well as a higher risk of esophagitis and history of upper airway malignancies. We finally observed that bile acids provided the best biometric parameters for diagnosis of LPR among the molecules tested.

Pepsin exposure in a non-acidic environment upregulates mucin 5AC (MUC5AC) expression via matrix metalloproteinase 9 (MMP9)/nuclear factor κB (NF-κB) in human airway epithelial cells

BACKGROUND

Gastric reflux (GR) is a backflow of gastric content to the aerodigestive tract. GR was previously found to be associated with inflammatory airway diseases and a potential cause of airway remodeling. Chronic exposure to gastric content may induce damage from nose to lung, because digestive enzymes and acidity are toxic to airway epithelial cells. Recently, the toxicity of pepsin in a non-acidic environment was found to increase proinflammatory cytokines and receptors in the epithelium of the aerodigestive tract. However, the effect of pepsin in non-acidic conditions on mucin expression has not been investigated in human airway epithelial cells. The purpose of this study was to evaluate the effect of pepsin on mucin 5AC (MUC5AC) expression in upper and lower airway epithelial cells as an important potential factor of non-acidic GR-related airway inflammation.

METHODS

In NCI-H292 cells and human nasal epithelial cells (HNEpCs), the effects and signaling pathways of pepsin on MUC5AC expression were examined using reverse-transcription polymerase chain reaction (RT-PCR), real-time PCR, enzyme immunoassay, zymography, Western blot, and immunofluorescence staining.

RESULTS

Pepsin increased MUC5AC expression in non-acidic condition of NCI-H292 cells and HNEpCs. Further, pepsin activated matrix metalloproteinase 9 (MMP9) and phosphorylated nuclear factor κB (NF-κB). Moreover, inhibitors of MMP9 and NF-κB significantly attenuated pepsin-induced MUC5AC expression, and the knockdown of NF-κB by small interfering RNA (siRNA) significantly blocked pepsin-induced MUC5AC expression in human airway epithelial cells.

CONCLUSION

These findings suggest that pepsin increased MUC5AC expression in non-acidic conditions via the activation of MMP9 and NF-κB in human airway epithelial cells.

Proximal reflux: biochemical mediators, markers, therapeutic targets, and clinical correlations

Airway reflux is implicated in the pathophysiology of a wide range of adult and pediatric upper and lower airway diseases. However, the diagnosis of proximal reflux-associated disease remains challenging due to evolving clinical criteria and institutional and regional variances in diagnostic practices. Evidence suggests that nonacidic contents of reflux may serve as both pathologic mediators of and biomarkers for reflux in the upper airway. Furthermore, they offer potential pharmaceutical and surgical intervention targets and are the focus of novel clinical diagnostic tools currently under investigation.

RNA Sequencing Reveals Cancer-Associated Changes in Laryngeal Cells Exposed to Non-Acid Pepsin

OBJECTIVE

Laryngopharyngeal reflux (LPR) is a common affliction that contributes to laryngeal inflammation, symptoms that impact quality of life, and life-threatening illnesses such as cancer. Effective treatment strategies for LPR are lacking. Pepsin is a proinflammatory and carcinogenic element of refluxate. Investigation of molecular pathways involved in pepsin-mediated damage may lead to identification of novel biomarkers and therapeutic targets for LPR. In this study, RNA sequencing was used to examine changes in human laryngeal epithelial cells following brief pepsin insult. Cells were immortalized to generate a model to aid future study of laryngeal injury and therapeutics.

STUDY DESIGN

In vitro translational.

METHODS

Laryngeal epithelial cells were cultured from a patient without signs or symptoms of LPR or laryngeal cancer. Cells were treated with 0.1 mg/ml pepsin for 1 hour or normal growth media (control) prior to RNA sequencing. Cells were immortalized via HPV E6/7 and characterized by microscopy, immunohistochemistry, G-banding, and soft agar assay.

RESULTS

Three hundred ninety-seven genes exhibited differences in expression with pepsin treatment (P < .05). Pathway analysis revealed association with cancer and related signaling processes including dysregulation of cancer-associated molecules, Metastasis-Associated Lung Adenocarcinoma Transcript 1 and KRT82, and the long-noncoding RNA, lipoprotein receptor-related protein 1 (LRP1)-AS, which regulates the putative pepsin receptor LRP1.

CONCLUSIONS

A single, brief exposure to pepsin activated cancer-associated signaling pathways in laryngeal cells in vitro, revealing novel mechanisms by which chronic reflux may contribute to carcinogenesis. The cell line developed herein represents a novel tool in which to investigate pepsin-dysregulated pathways identified by RNA sequencing and disparities of tumor proneness of laryngeal subsites.

LEVEL OF EVIDENCE

N/A Laryngoscope, 131:121-129, 2021.

Upper Endoscopy in Patients with Extra-Oesophageal Reflux Symptoms: A Multicentre Study

Background

There are no evidence-based recommendations for performing upper gastrointestinal endoscopy (UGIE) in patients with extra-oesophageal symptoms of gastro-oesophageal reflux disease (GORD). However, UGIEs are often performed in clinical practice in these patients. We aimed to assess the prevalence of gastro-oesophageal lesions in patients with atypical GORD symptoms.

Methods

Patients complaining of at least one extra-oesophageal GORD symptom and undergoing UGIE in seven centres were prospectively enrolled. Clinically relevant lesions (Barrett's oesophagus, erosive oesophagitis, gastric precancerous conditions, peptic ulcer, cancer, and H. pylori infection) were statistically compared between groups regarding GORD symptoms (atypical vs. both typical and atypical), type of atypical symptoms, age, and presence of hiatal hernia.

Results

Two hundred eleven patients were enrolled (male/female: 74/137; mean age: 55.5 ± 14.7 years). Barrett's oesophagus was detected in 4 (1.9%), erosive oesophagitis in 12 (5.7%), gastric precancerous conditions in 22 (10.4%), and H. pylori infection in 38 (18%) patients. Prevalence of clinically relevant lesions was lower in patients with only atypical GORD symptoms (28.6 vs. 42.5%; p = 0.046; χ² test), in patients ≤50 years (20 vs. 44.8%; p = 0.004; χ² test), and in those in ongoing proton pump inhibitor (PPI) therapy (21.1 vs. 40.2%; p = 0.01; χ² test). No clinically relevant lesions were detected in patients ≤50 years, without alarm symptoms, and receiving PPI therapy. Hiatal hernia was diagnosed in only 6 patients with cardiologic and in 41 patients with ear-nose-throat symptoms (11.3 vs. 35.1%; p = 0.03; χ² test).

Conclusions

Clinically relevant lesions are uncommon among young (≤50 years) patients with extra-oesophageal GORD symptoms. Hiatal hernia is not more prevalent in patients with cardiologic symptoms and suspicion of GORD. The usefulness of UGIE in these patients is questionable.

Validation in China of a non-invasive salivary pepsin biomarker containing two unique human pepsin monoclonal antibodies to diagnose gastroesophageal reflux disease

OBJECTIVES

Peptest is a new non-invasive reflux diagnostic test based on lateral flow technology that containing two highly specific human pepsin monoclonal antibodies for detecting pepsin, a biomarker for reflux disease. The primary aim of this multicenter clinical study was to validate the efficacy of Peptest in patients diagnosed with gastroesophageal reflux and healthy controls in China.

METHODS

Patients with suspected gastroesophageal reflux underwent an endoscopy and were classified into non-erosive reflux disease and erosive esophagitis subgroups. A healthy control group was also recruited. All participants were given a reflux disease questionnaire-patients scoring greater than 12 and controls scoring zero. All participants provided a postprandial saliva sample and most patients gave an additional post-symptom sample for pepsin analysis.

RESULTS

Altogether 1032 participants aged between 19 and 78 years were recruited. They consisted of 488 patients with non-erosive reflux disease, 221 with erosive esophagitis and 323 healthy controls. The number of postprandial and post-symptom samples analyzed totaled 1031 and 692, respectively. The results across all centers showed an overall pepsin-positive sensitivity of 85%, a specificity of 60%, a positive predictive value of 82%, a negative predictive value of 65% and a positive likelihood ratio of 2.12.

CONCLUSION

The sensitivity of Peptest was high, but the specificity achieved in some centers was low, resulting overall in only a moderate specificity. Further diagnostic investigative studies are warranted.

Optimized Generation of Primary Human Epithelial Cells from Larynx and Hypopharynx: A Site-Specific Epithelial Model for Reflux Research

Laryngopharyngeal reflux (LPR) induces a differential damage effect on several anatomic sites within the larynx and hypopharynx; therefore, an in vitro model is needed for each anatomic site. This study aimed to establish a primary culture method for human laryngeal and hypopharyngeal epithelial cells derived from multiple anatomic sites. Surgical mucosa specimens were treated with a two-step enzymatic strategy to establish a primary culture. Of the 46 samples, primary cultivation was achieved successfully with 36 samples, and the positive ratio was 78.3%. In addition, flow cytometry revealed that these primary cells were epithelial cells with a purity of 94.9%. The proliferative ability was confirmed by positive staining for Ki-67. Laryngeal and hypopharyngeal epithelial cells from multiple sites exhibited similar epithelial morphology and positive cytokeratin expression. These cells can be cultured to passage 4. In summary, we successfully established the in vitro epithelial model of larynx and hypopharynx subsites, which may potentially be used as a platform for reflux research, especially for site-specific damage effect.

The role of pepsin in epithelia-mesenchymal transition in idiopathic subglottic stenosis

OBJECTIVES

Idiopathic subglottic stenosis (iSGS) is commonly characterized by laryngeal fibrosis thought to arise by epithelia-mesenchymal transition (EMT) induced by chronic inflammation. Pepsin is a potent inducer of inflammation in the airways during chronic laryngopharyngeal reflux and has been observed in the subglottic mucosa of patients with iSGS, absent in normal mucosa. The aim of this study was to examine the effect of pepsin on mechanisms of EMT in laryngeal cells with implications for iSGS.

STUDY DESIGN

In vitro translational research study.

METHODS

Human laryngeal epithelial cell cultures were exposed to 0.1 mg/mL or 1.0 mg/mL pepsin at pH7 for 24 and 48 hours, or media pH5 ± 0.1 mg/mL pepsin for 10 minutes and harvested after 24 and 48 hours. EMT marker expression was measured by qPCR and enzyme-linked immunosorbent assays. Wound-healing scratch assay was performed on immortalized human vocal fold fibroblasts pretreated with media pH5 ± 0.1 mg/mL pepsin (10 minutes) or continuously treated with media pH7 ± 0.1 to 1 mg/mL pepsin for 24 hours.

RESULTS

Pepsin yielded no effect on MMP1, MMP9, FN1, COL1A1, HAS2, or CDH1 gene expression or matrix metalloproteinase-9 or fibronectin protein expression, either alone or in the presence of weak acid. Pepsin and/or acid produced no effect on fibroblast migration.

CONCLUSION

Whereas pepsin has been shown to be present in the subglottic mucosa of patients with iSGS, this in vitro acute exposure investigation does not provide evidence of a direct causal role for development of fibrosis in subglottic epithelial cell cultures.

LEVELS OF EVIDENCE

NA. Laryngoscope, 130:154-158, 2020.

Gastro-Oesophageal Reflux and Aspiration: Does Laparoscopic Fundoplication Significantly Decrease Pulmonary Aspiration?

PURPOSE

Pulmonary aspiration of gastric refluxate is one of the indications for anti-reflux surgery. Effectiveness of surgery in preventing pulmonary aspiration post-operatively has not been previously tested. The aim of this project is to assess effectiveness of anti-reflux surgery on preventing pulmonary aspiration of gastric refluxate.

METHODS

Retrospective analysis of prospectively populated database of patients with confirmed aspiration of gastric refluxate on scintigraphy. Patients that have undergone anti-reflux surgery between 01/01/2014 and 31/12/2015 and had scintigraphy post-operatively were included. Objective data such as resolution of aspiration, degree of proximal aero-digestive contamination, surgical complications and oesophageal dysmotility as well as patient quality of life data were analysed.

RESULTS

Inclusion criteria were satisfied by 39 patients (11 male and 28 female). Pulmonary aspiration was prevented in 24 out of 39 patients (61.5%) post-operatively. Significant reduction of isotope contamination of upper oesophagus supine and upright (p = 0.002) and pharynx supine and upright (p = 0.027) was confirmed on scintigraphy post-operatively. Severe oesophageal dysmotility was strongly associated with continued aspiration post-operatively OR 15.3 (95% CI 2.459-95.194; p = 0.02). Majority (24/31, 77%) of patients were satisfied or very satisfied with surgery, whilst 7/31 (23%) were dissatisfied. Pre-operative GIQLI scores were low (mean 89.77, SD 20.5), modest improvements at 6 months (mean 98.4, SD 21.97) and deterioration at 12 months (mean 88.41, SD 28.07) were not significant (p = 0.07).

CONCLUSION

Surgery is partially effective in reversing pulmonary aspiration of gastric refluxate on short-term follow-up. Severe oesophageal dysmotility is a predictor of inferior control of aspiration with surgery.

Reflux Finding Score (RFS) a Quantitative Guide for Diagnosis and Treatment of Laryngopharyngeal Reflux

The study was under taken to know the prevalence of reflux signs in an individuals with throat complaints on the basis of reflux finding score (RFS) and quantitatively assess the effect of treatment. A cross-sectional study was done to evaluate the presence of laryngo-pharyngeal reflux signs in patients visiting ENT clinic with throat or voice problems in central India. There were 80 patients included in the study from 2017 to 2018 individuals. They were questioned regarding their symptoms. Their pharyngeal findings on rigid 70° laryngoscopy were viewed and RFS was made. The patients were reviewed at monthly intervals. Laryngopharyngeal reflux changes were seen in 36 of the 80 patients (45%). The reflux was graded as per the reflux finding score. The score ranged from 7 to maximum of 17 out of 26 in the patients with LPRD. Majority of the patients the score decreased with lifestyle changes and pantaprazole twice daily. There was poor response in 5% (4) patients, who were then advised to undergo upper gastro intestinal endoscopy for further assessment. Laryngopharyngeal reflux has become a very common entity in urban lifestyle. On careful examination the signs can be picked and assessed with the RFS, which is a very useful tool to grade and reassess patient on subsequent follow up.

Proton pump inhibitor-refractory gastroesophageal reflux disease: challenges and solutions

A significant percentage of patients with gastroesophageal reflux disease (GERD) will not respond to proton pump inhibitor (PPI) therapy. The causes of PPI-refractory GERD are numerous and diverse, and include adherence, persistent acid, functional disorders, nonacid reflux, and PPI bioavailability. The evaluation should start with a symptom assessment and may progress to imaging, endoscopy, and monitoring of esophageal pH, impedance, and bilirubin. There are a variety of pharmacologic and procedural interventions that should be selected based on the underlying mechanism of PPI failure. Pharmacologic treatments can include antacids, prokinetics, alginates, bile acid binders, reflux inhibitors, and antidepressants. Procedural options include laparoscopic fundoplication and LINX as well as endoscopic procedures, such as transoral incisionless fundoplication and Stretta. Several alternative and complementary treatments of possible benefit also exist.

The Emerging Role of The Eosinophil and Its Measurement in Chronic Cough

Although the aetiology of chronic cough in guidelines is clearly stated as asthma and related syndromes, gastro-oesophageal reflux disease (GORD), and upper airways disease, the inflammatory mechanisms underlying these conditions differ. Recent studies on asthma have increasingly focused on its molecular phenotypes instead of clinical characteristics. Here, we proposed the hypothesis that divides cough into two groups; the eosinophilic and neutrophilic. This division will enhance our ability to recognise the type of airway inflammation which, as a consequence will lead us to more targeted and personalized treatment approaches.

Association between Laryngeal Pepsin Levels and the Presence of Vocal Fold Polyps

Objective

To determine whether pepsin, the main component of refluxed gastric contents, is significantly associated with vocal fold polyps and to evaluate the diagnostic value of pepsin in vocal fold polyps’ tissues.

Study Design

Cross-sectional study.

Setting

Nanfang Hospital of Southern Medical University.

Subjects and Methods

The study included 32 patients with vocal fold polyps and 16 healthy controls between 2011 and 2012. Reflux symptom index and reflux finding score assessments, 24-hour combined multichannel intraluminal impedance and pH monitoring, and biopsy of the vocal fold polyp tissues or posterior laryngeal mucosa (healthy controls) for immunohistochemical pepsin staining were performed.

Results

The expression of pepsin was significantly higher in patients with vocal fold polyps than in controls (28/32, 75% vs 5/16, 31.25%; P < .001). The pepsin levels were significantly positively correlated with upright position pharyngeal acid reflux and esophageal reflux parameters adjusted by age. Based on pepsin staining data, the sensitivity and negative predictive values of 24-hour pH monitoring, the reflux symptom index, and the reflux finding score were 70% to 84.62%, whereas their specificity and positive predictive values were relatively low (20%-31.58%).

Conclusion

Pepsin reflux may be a risk factor for vocal fold polyps formation. In addition, pepsin immunohistochemical analysis of polyp biopsy samples appears to be a more sensitive and effective test for diagnosing laryngopharyngeal reflux than the reflux symptom index, the reflux finding score, and 24-hour pH monitoring in a clinical setting.

Long-term Outcomes of Patients Receiving a Magnetic Sphincter Augmentation Device for Gastroesophageal Reflux

BACKGROUND & AIMS

Based on results from year 2 of a 5-year trial, in 2012 the US Food and Drug Administration approved the use of a magnetic device to augment lower esophageal sphincter function in patients with gastroesophageal reflux disease (GERD). We report the final results of 5 years of follow-up evaluation of patients who received this device.

METHODS

We performed a prospective study of the safety and efficacy of a magnetic device in 100 adults with GERD for 6 months or more, who were partially responsive to daily proton pump inhibitors (PPIs) and had evidence of pathologic esophageal acid exposure, at 14 centers in the United States and The Netherlands. The magnetic device was placed using standard laparoscopic tools and techniques. Eighty-five subjects were followed up for 5 years to evaluate quality of life, reflux control, use of PPIs, and side effects. The GERD-health-related quality of life (GERD-HRQL) questionnaire was administered at baseline to patients on and off PPIs, and after placement of the device; patients served as their own controls. A partial response to PPIs was defined as a GERD-HRQL score of 10 or less on PPIs and a score of 15 or higher off PPIs, or a 6-point or more improvement when scores on vs off PPI were compared.

RESULTS

Over the follow-up period, no device erosions, migrations, or malfunctions occurred. At baseline, the median GERD-HRQL scores were 27 in patients not taking PPIs and 11 in patients on PPIs; 5 years after device placement this score decreased to 4. All patients used PPIs at baseline; this value decreased to 15.3% at 5 years. Moderate or severe regurgitation occurred in 57% of subjects at baseline, but only 1.2% at 5 years. All patients reported the ability to belch and vomit if needed. Bothersome dysphagia was present in 5% at baseline and in 6% at 5 years. Bothersome gas-bloat was present in 52% at baseline and decreased to 8.3% at 5 years.

CONCLUSIONS

Augmentation of the lower esophageal sphincter with a magnetic device provides significant and sustained control of reflux, with minimal side effects or complications. No new safety risks emerged over a 5-year follow-up period. These findings validate the long-term safety and efficacy of the magnetic sphincter augmentation device for patients with GERD. ClinicalTrials.gov no: NCT00776997.

Local Synthesis of Pepsin in Barrett's Esophagus and the Role of Pepsin in Esophageal Adenocarcinoma

OBJECTIVE

Despite widespread use of proton pump inhibitors (PPIs), the incidence of esophageal adenocarcinoma (EAC) continues to rise. PPIs reduce reflux acidity, but only transiently inactivate gastric enzymes. Nonacid reflux, specifically nonacid pepsin, contributes to carcinogenesis in the larynx. Given the carcinogenic potential of pepsin and inefficacy of PPIs to prevent EAC, the presence and effect of pepsin in the esophagus should be investigated.

METHODS

Normal and Barrett's biopsies from 8 Barrett's esophagus patients were collected for pepsin analysis via Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR). Human esophageal cells cultured from healthy patients were treated with pepsin (0.01-1 mg/mL; 1-20 hours), acid (pH 4)±pepsin (5 minutes); real-time RT-PCR, ELISA, and cell migration were assayed.

RESULTS

Pepsin was detected in all 8 Barrett's and 4 of 8 adjacent normal specimens. Pepsinogen mRNA was observed in 22 Barrett's, but not in normal adjacent samples. Pepsin induced PTSG2 (COX-2) and IL-1β expression and cell migration in vitro.

CONCLUSIONS

Pepsin is synthesized by metaplastic, Barrett's esophageal mucosa. Nonacid pepsin increases metrics of tumorigenicity in esophageal epithelial cells in vitro. These findings implicate refluxed and locally synthesized pepsin in development and progression of EAC and, in part, explain the inefficacy of PPIs in the prevention of EAC.

Alginate as a protease inhibitor in vitro and in a model gut system; selective inhibition of pepsin but not trypsin

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Alginate inhibits proteolytic activity of pepsin but not trypsin.

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Level of pepsin inhibition correlates with alginate F[M].

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An in vitro model gut system was used to model alginate inhibition of proteolysis.

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Proteolysis inhibited in gastric phase of digestion, but not small intestinal phase.

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pH dependent ionic interactions reduce substrate availability at pH 2.5.

Alginates are widely used in the food and medical industries, including as a Gastro-Oesophagul Reflux treatment. This work investigates the inhibitory effects of alginate on the reflux aggressors trypsin and pepsin and the role of alginate-substrate binding, pH and alginate structure on inhibition. Alginates were shown to reduce pepsin activity by up to 53.9% (±9.5SD) in vitro. Strong positive correlation between alginate mannuronate residue frequency and levels of pepsin inhibition was observed. Limited inhibition of trypsin was shown. Viscometric observations of pH dependent interactions between alginate and protein suggest a mechanism whereby pH dependent ionic interactions reduce substrate availability to enzyme at acidic pH. To understand how dietary protein digestion is affected by alginate, proteolytic digestion was investigated in an in vitro model of the upper digestive tract. Significant inhibition of proteolysis was shown in the gastric phase of digestion, but not the small intestinal phase.

Upper esophageal and pharyngeal cancers

The following, from the 12th OESO World Conference: Cancers of the Esophagus, includes commentaries on laryngopharyngeal reflux as a risk factor for laryngeal cancer; the role of pepsin in laryngopharyngeal neoplasia; natural fruit and vegetable compounds for the prevention and treatment of pharyngeal and esophageal cancers; and evaluation of cranberry constituents as inhibitors of esophageal adenocarcinoma utilizing in vitro assay and in vivo models.

Identifying asthma triggers

Asthma has many triggers including rhinosinusitis; allergy; irritants; medications (aspirin in aspirin-exacerbated respiratory disease); and obesity. Paradoxic vocal fold dysfunction mimics asthma and may be present along with asthma. This article reviews each of these triggers, outlining methods of recognizing the trigger and then its management. In many patients more than one trigger may be present. Full appreciation of the complexity of these relationships and targeted therapy to the trigger is needed to best care for the patient with asthma.

Gastroesophageal reflux as a cause of chronic cough, severe asthma, and migratory pulmonary infiltrates

Gastroesophageal reflux (GER), asthma-type cough and upper airway disease are the most common causes of chronic cough syndrome. We present a case in which impedance–pH monitoring indicated severe mixed acid–nonacid esophageal reflux reaching the upper third of the esophagus in 75% of nonacid events. GER and the associated aspiration episodes were shown to be the cause of severe asthma attacks and migratory pulmonary infiltrates. GER was caused by a sleeve gastrectomy, which seriously disabled the mechanisms preventing reflux from reaching the airways. Respiratory symptoms improved notably after abdominal surgery to correct the GER, suggesting a close causal relationship between GER and all the symptoms, including asthma. However, this issue remains unresolved in the literature.

Optimal treatment of laryngopharyngeal reflux disease

Laryngopharyngeal reflux is defined as the reflux of gastric content into larynx and pharynx. A large number of data suggest the growing prevalence of laryngopharyngeal symptoms in patients with gastroesophageal reflux disease. However, laryngopharyngeal reflux is a multifactorial syndrome and gastroesophageal reflux disease is not the only cause involved in its pathogenesis. Current critical issues in diagnosing laryngopharyngeal reflux are many nonspecific laryngeal symptoms and signs, and poor sensitivity and specificity of all currently available diagnostic tests. Although it is a pragmatic clinical strategy to start with empiric trials of proton pump inhibitors, many patients with suspected laryngopharyngeal reflux have persistent symptoms despite maximal acid suppression therapy. Overall, there are scant conflicting results to assess the effect of reflux treatments (including dietary and lifestyle modification, medical treatment, antireflux surgery) on laryngopharyngeal reflux. The present review is aimed at critically discussing the current treatment options in patients with laryngopharyngeal reflux, and provides a perspective on the development of new therapies.

Posterior laryngitis: a disease with different aetiologies affecting health-related quality of life: a prospective case-control study

BACKGROUND

Laryngo-pharyngeal reflux (LPR) is assumed to be the most common cause of posterior laryngitis (PL). Since LPR is found in healthy subjects, and PL patients are not improved by acid-reducing therapy, other aetiologies to PL must be considered. The aims of this study in PL were to investigate the prevalence of acid reflux in the proximal oesophagus and functional gastrointestinal symptoms, to analyse motilin levels in plasma, and to assess health-related quality of life (HRQOL) before and after treatment.

METHODS

Forty-six patients (26 women), with verified PL, median age 55 (IQR 41-68) years, were referred to oesophago-gastro-duodenoscopy and 24-h pH monitoring. Plasma motilin was analysed. The 36-item Short-Form questionnaire was completed at inclusion and at follow-up after 43±14 months, when also the Visual Analogue Scale for Irritable Bowel Syndrome was completed. Values were compared to controls. Treatment and relief of symptoms were noted from medical records.

RESULTS

Thirty-four percent had proximal acid reflux and 40% showed signs of distal reflux. Ninety-four percent received acid-reducing treatment, with total relief of symptoms in 17%. Patients with reflux symptoms had lower plasma motilin levels compared to patients without reflux symptoms (p = 0.021). The HRQOL was impaired at inclusion, but improved over time. Patients, especially men, had more functional gastrointestinal symptoms than controls.

CONCLUSIONS

This study indicates that a minority of patients with PL has LPR and is cured by acid-reducing therapy. Disturbed plasma motilin levels and presence of functional gastrointestinal symptoms are found in PL. The impaired HRQOL improves over time.

Summary of papers presented at the 2012 seventh international cough symposium

Twenty six papers were presented as posters in the Seventh International Symposium on Cough; 12 papers were presented in the Basic Science of Cough session, and 14 papers presented in the Clinical Science of Cough session. These papers explored a wide spectrum of cough-related areas including pathophysiological mechanisms, treatment and detection of cough, and symptom assessment and perception, and were grouped into several general themes for facilitate the discussion. Studies presented in these posters have provided new information that should improve our knowledge on the basic physiology and pharmacology of cough, and the peripheral and central neural mechanisms involved in the generation of the cough motor pattern. In addition, in the clinical science section, studies reporting potential new anti-tussive agents and further characterisation of cough symptoms and perception have provided a base for the fruitful strategies for the development of novel anti-tussive therapies and cough management.

Antibodies against gonadotropin-releasing hormone in patients with posterior laryngitis

Patients with functional gastrointestinal disorders express antibodies against gonadotropin-releasing hormone (GnRH) in serum. One common cause of posterior laryngitis (PL) is extra-esophageal reflux, but a functional etiology has also been suggested. The aim of this study was to scrutinize patients with PL with regard to the presence of GnRH antibodies and to examine the association between antibodies and symptoms and reflux. Consecutive PL patients were included after examination. Serum was analyzed for the presence of antibodies using an enzyme-linked immunosorbent assay (ELISA) method and expressed as relative units (RU). Two age- and gender-matched healthy subjects per case served as controls. The prevalence of IgM GnRH antibodies in patients was 35% compared with 28% in controls (P = 0.06), with higher levels in patients (0.8 (0.3-2.2) RU) than in controls (0.2 (0.1-0.6) RU) (P = 0.007). The corresponding IgG antibody prevalences were 43% and 4%, respectively (P = 0.001), with no difference in levels (P = 0.70). There was no association between antibodies and clinical findings.

Pepsin promotes proliferation of laryngeal and pharyngeal epithelial cells

OBJECTIVE/HYPOTHESIS

Laryngopharyngeal reflux (LPR) is thought to be a significant risk factor for laryngeal squamous cell carcinoma (SCC), but causality has never been proven. It is accepted that chronic reflux into the esophagus can induce metaplastic changes in esophageal mucosa with subsequent increased risk of esophageal adenocarcinoma, but no similar associations have been established for LPR and laryngopharyngeal SCC. The objective of this study was to test the hypothesis that reflux of pepsin into the laryngopharynx can promote carcinogenesis.

STUDY DESIGN

Translational research study.

METHODS

Normal human laryngeal primary epithelial cell cultures and hypopharyngeal FaDu SCC cells were exposed to human pepsin and analyzed by Human Cancer PathwayFinder and miRNA Superarrays, flow cytometry, and Western blot to determine the effect of pepsin on carcinogenesis. Laryngeal biopsy specimens taken from cancer patients and normal control subjects were analyzed for the presence of pepsin by Western blot.

RESULTS

Microarray analysis demonstrated that pepsin significantly altered the expression of 27 genes implicated in carcinogenesis and also affected the expression of 22 microRNAs known to be altered in human head and neck cancers. Pepsin increased proliferation in both FaDu SCC cells and cultured normal laryngeal epithelial primary cells by increasing S phase distribution on flow cytometry analysis in a time- and dose-dependent manner. Furthermore, pepsin was detected in 60% (3/5) human laryngeal cancer biopsies, absent in all (0/5) normal control specimens.

CONCLUSIONS

These data support a role for refluxed pepsin in the promotion of epithelial proliferation and carcinogenesis of the larynx and pharynx.

Role for ion transport in porcine vocal fold epithelial defense to acid challenge

OBJECTIVE

The vocal fold epithelium is routinely exposed to gastric contents, including acid and pepsin, during laryngopharyngeal reflux events. The epithelium may possess intrinsic defenses to reflux. The first objective of the current study was to examine whether vocal fold epithelial ion transport is one potential mechanism of defense to gastric contents. The second objective was to determine whether ion transport in response to gastric contents is associated with the secretion of bicarbonate.

STUDY DESIGN

Prospective design in excised porcine larynges.

SETTING

Laboratory.

SUBJECTS AND METHODS

Porcine vocal folds (N = 56) were exposed on the luminal surface to acid, pepsin, or sham challenges. Ion transport at baseline and following challenge exposure was measured using electrophysiological techniques. To examine specific ion transport mechanisms, vocal folds were pretreated with either a sodium channel blocker or bicarbonate channel blocker.

RESULTS

Within 60 seconds of acid but not pepsin exposure, there was a significant increase in ion transport. This rapid increase in ion transport was transient and related to bicarbonate secretion.

CONCLUSION

The current data suggest that porcine vocal folds immediately increase bicarbonate secretion following exposure to acid. Bicarbonate secretion may act to neutralize acid. These findings contribute to the identification of the mechanisms underlying vocal fold defense to reflux and offer implications for the development of treatments for reflux-induced vocal fold injury.

Reflux revisited: advancing the role of pepsin. Int J Otolaryngol. 2012;2012:646901. [PMID: 22242022 PMCID: PMC3216344 DOI: 10.1155/2012/646901]

Gastroesophageal reflux disease is mediated principally by acid. Today, we recognise reflux reaches beyond the esophagus, where pepsin, not acid, causes damage. Extraesophageal reflux occurs both as liquid and probably aerosol, the latter with a further reach. Pepsin is stable up to pH 7 and regains activity after reacidification. The enzyme adheres to laryngeal cells, depletes its defences, and causes further damage internally after its endocytosis. Extraesophageal reflux can today be detected by recognising pharyngeal acidification using a miniaturised pH probe and by the identification of pepsin in saliva and in exhaled breath condensate by a rapid, sensitive, and specific immunoassay. Proton pump inhibitors do not help the majority with extraesophageal reflux but specifically formulated alginates, which sieve pepsin, give benefit. These new insights may lead to the development of novel drugs that dramatically reduce pepsinogen secretion, block the effects of adherent pepsin, and give corresponding clinical benefit."For now we see through a glass, darkly."-First epistle, Chapter 13, Corinthians.

Diagnosing GORD in Respiratory Medicine

Gastroesophageal reflux disease (GORD) is increasing in prevalence and is highly associated with several lung diseases such as asthma and COPD. Current diagnostic methods are imperfect, being insensitive, non-specific, expensive, or invasive. An accurate diagnosis of GORD can aid effective treatment and have significant clinical impact. Novel methods such as exhaled breath condensate analysis and electronic nose technology have the potential to improve the accuracy of diagnosing GORD.