Upper-airway cough syndrome with latent eosinophilic bronchitis

How to diagnose GERC more effectively: reflections on post-reflux swallow-induced peristaltic wave index and mean nocturnal baseline impedance

INTRODUCTION

Post-reflux swallow-induced peristaltic wave index (PSPWI) and mean nocturnal baseline impedance (MNBI) are novel parameters reflect esophageal clearance capacity and mucosal integrity. They hold potential in aiding the recognition of gastroesophageal reflux-induced chronic cough (GERC). Our study aims to investigate their diagnostic value in GERC.

METHODS

This study included patients suspected GERC. General information and relevant laboratory examinations were collected, and final diagnosis were determined following guidelines for chronic cough. The parameters of multichannel intraluminal impedance-pH monitoring (MII-pH) in patients were analyzed and compared to explore their diagnostic value in GERC.

RESULTS

A total of 186 patients were enrolled in this study. The diagnostic value of PSPWI for GERC was significant, with the area under the working curve (AUC) of 0.757 and a cutoff value of 39.4%, which was not statistically different from that of acid exposure time (AET) (p > 0.05). The combined diagnostic value of AET > 4.4% and PSPWI < 39.4% was superior to using AET > 4.4% alone (p < 0.05). Additionally, MNBI and distal MNBI also contributed to the diagnosis of GERC, with AUC values of 0.639 and 0.624, respectively. AET > 4.4% or PSPWI < 39.4% is associated with a 44% reduction in missed diagnoses of non-acid GERC compared to AET > 6.0% or symptom association probability (SAP) ≥ 95%, and may be more favorable for identifying GERC.

CONCLUSION

The diagnostic value of PSPWI for GERC is comparable to that of AET. Combining PSPWI < 39.4% or AET > 4.4% can improve the diagnostic efficiency by reducing the risk of missed diagnoses in cases where non-acid reflux is predominant. Distal MNBI and MNBI can serve as secondary reference indices in the diagnosis of GERC.

Post-reflux swallow-induced peristaltic wave index: a new parameter for the identification of non-acid gastroesophageal reflux-related chronic cough

BACKGROUND

The current available diagnostic criteria for gastroesophageal reflux-related chronic cough (GERC) dominated by non-acid reflux is imperfect. The post-reflux swallow-induced peristaltic wave index (PSPWI) is a parameter reflecting esophageal clearance function.

OBJECTIVES

This study aims to investigate its diagnostic value for non-acid GERC.

DESIGN

This study sought to compare the diagnostic value of PSPWI in different types of GERC, particularly non-acid GERC, and explore the clinical significance of PSPWI in the diagnosis of non-acid GERC through diagnostic experiments.

METHODS

A retrospective analysis was performed based on 223 patients with suspected GERC who underwent multichannel intraluminal impedance-pH monitoring (MII-pH) in the outpatient clinic of our department from August 2016 to June 2021. Their clinical information, laboratory test results, and treatment responses were assessed and the underlying etiologies of chronic cough were categorized. The predictive value of the PSPWI in diagnosing different types of GERC, especially non-acid GERC, was analyzed and compared.

RESULTS

A total of 195 patients with chronic cough who met the inclusion criteria underwent MII-pH monitoring. 143 patients had a definitive diagnosis of GERC, including 98 with acid GERC and 45 with non-acid GERC. The diagnostic value of PSPWI alone was moderate for GERC with an area under the working curve (AUC) 0.760, but poor for non-acid GERC with an AUC of 0.569. However, PSPWI < 39.8% combining with acid exposure time (AET) ⩽ 6.2% demonstrated a moderate diagnostic value for non-acid GERC, with an AUC of 0.722. When PSPWI < 39.8% combined with a non-acid reflux ratio >68.75%, the diagnostic value for non-acid GERC was improved (AUCROC = 0.80 versus AUCROC = 0.722, p < 0.05), which was significantly superior to non-acid symptom index (AUCROC = 0.804 versus AUCROC = 0.550, p < 0.05) and non-acid symptom association probability (AUCROC = 0.804 versus AUCROC = 0.571, p < 0.05).

CONCLUSION

PSPWI < 39.8% and AET ⩽ 6.2% have demonstrated good diagnostic value for non-acid GERC. The diagnostic value was further improved when combined with non-acid reflux ratio >68.75%.

Psychological morbidity and chronic cough: which is predominant? A comparison of clinical characteristics

Background

The clinical characteristics of chronic cough with pre-existing psychological co-morbidity (PCC) and chronic cough with secondary anxiety and depression (SCC) were compared to provide a basis for diagnosing and treating psychological co-morbidities in people with chronic cough.

Methods

A prospective study was conducted to analyze the general clinical data between the PCC, SCC, and the chronic cough without anxiety and depression (CC) groups. A total of 203 patients with chronic cough were enrolled in the study. The final diagnosis was made in all cases using a combination of psychosomatic and respiratory diagnoses. The three groups' general clinical data, capsaicin cough sensitivity, cough symptom score, Leicester cough questionnaire (LCQ), and psychosomatic scale scores were compared among the three groups. The diagnostic value of the patient health questionnaire (PHQ)-9 and general anxiety disorder (GAD)-7 in patients with PCC and the follow-up information were analyzed.

Results

Compared with the SCC group, the duration of cough in the PCC group was shorter (H = -3.54, p = 0.001), the night cough symptoms were milder (H = -4.60, p < 0.001), the total LCQ score was lower (H = -2.97, p = 0.009), and the PHQ-9 (H = 2.90, p = 0.011) and GAD-7 scores (H = 2.71, p = 0.002) were higher. When using PHQ-9 and GAD-7 scores for the combined prediction and diagnosis of PCC, the area under the curve (AUC) was 0.88, and the sensitivity and specificity were 90.0% and 73.85%, respectively. After 8 weeks of psychosomatic treatment, cough symptoms improved in the PCC group, but the psychological improvement was not significant. The psychological status of the SCC group improved after cough symptoms were ameliorated by etiologic or empirical treatment.

Conclusion

The clinical characteristics of patients with PCC and SCC are different. The evaluation of psychosomatic scales is of value to distinguish between the two groups. Chronic cough patients with psychological co-morbidity benefit from the combined diagnosis of psychosomatic medicine in a timely fashion. PCC requires more attention in psychological therapy, but for SCC, targeting etiological treatment of the cough is preferred.

Trial registration

The protocol was registered in the Chinese Clinical Trials Register (http://www.chictr.org.cn/) [ChiCTR2000037429].

Can acid exposure time replace the DeMeester score in the diagnosis of gastroesophageal reflux-induced cough?

Background:

The objective of this study was to compare the predictive accuracy of the acid exposure time (AET) with the DeMeester score (DMS) for gastroesophageal reflux–induced cough (GERC).

Methods:

A total of 277 patients who underwent multichannel intraluminal impedance pH monitoring (MII-pH) were enrolled, and their clinical information and laboratory results were retrospectively analyzed. The diagnostic value of AET for GERC was compared with that of the DMS, symptom association probability (SAP), and symptom index (SI).

Results:

A total of 236 patients met the inclusion criteria, 150 patients (63.65%) were definitely diagnosed with GERC, including 111(74%) acid GERC and 39 (26%) nonacid GERC. The optimal cutoff value of AET for diagnosing GERC was AET > 4.8%, and its diagnostic value was equal to that of DMS > 14.7 (AUC = 0.827 versus 0.818, p = 0.519) and was superior to that of SAP (AUC = 0.827 versus 0.689, p = 0.000) and SI (AUC = 0.827 versus 0.688, p = 0.000). When using both DMS > 14.7 and AET > 4.8% or either of the two for the diagnosis of GERC, the diagnosis rate was not improved over using DMS > 14.7 alone. The diagnostic value of AET and DMS for acid GERC were both high and equivalent (AUC = 0.925 versus 0.922, p = 0.95). The optimal cutoff value of AET for diagnosing acid GERC was AET > 6.2%.

Conclusion:

AET and DMS are both equal in discriminating GERC. A GERC diagnosis should be considered when AET > 4.8%, whereas an acid GERC diagnosis should be considered when AET > 6.2%.

Reflux characteristics in patients with gastroesophageal reflux-related chronic cough complicated by laryngopharyngeal reflux

Background

This study aimed to investigate the reflux characteristics in patients with gastroesophageal reflux-related chronic cough (GERC) complicated by laryngopharyngeal reflux (LPR).

Methods

Patients with chronic cough were recruited. Reflux symptom index (RSI) scoring, cough symptom scoring, assessment of capsaicin cough sensitivity, and multichannel intraluminal impedance and pH monitoring (MII-pH) were performed.

Results

RSI score in GERC patients was significantly higher than that in patients with atopic cough (AC), cough variant asthma, eosinophilic bronchitis (EB), and upper airway cough syndrome (UACS) (P<0.05). The RSI score in non-acid GERC patients was significantly higher than that in acid GERC patients (P=0.003). The cut-off value of the RSI score was defined as 19 during diagnosis of non-acid GERC. In the RSI ≥19 group, there was more proximal reflux and more significant gas and non-acid reflux, and the efficacy of a combined use of baclofen or gabapentin was better than that of the RSI <19 group (P<0.05). The efficacy of proton pump inhibitor (PPI) at a routine dosage together with prokinetic agents in the RSI <19 group was better than that in the RSI ≥19 group (P=0.009).

Conclusions

LPR overlaps with GERC in part. GERC patients with higher RSI scores may present more proximal reflux, non-acid reflux, and gas reflux, and get better efficacy with neuromodulators (gabapentin or baclofen) used as an add-on therapy.

Changing etiological frequency of chronic cough in a tertiary hospital in Shanghai, China

Background

The frequency distributions of the etiologies of chronic cough have changed over time. This study aimed to investigate the changing etiological frequency of chronic cough in a tertiary hospital in Shanghai, China, and to explore the clinical significance.

Methods

Medical records of 1,311 patients with chronic cough who visit our hospital between January 2009 and December 2016 were retrospectively reviewed. The etiologies of chronic cough were identified according to a standardized step-by-step diagnostic protocol and the changes in the etiological frequency of chronic cough over the years were using the Chi-squared (χ²) test.

Results

Cough variant asthma (CVA) (449/1,311, 34.2%), gastroesophageal reflux-related chronic cough (GERC) (374/1,311, 28.5%), upper airway cough syndrome/postnasal drip syndrome (UACS/PNDs) (241/1,311, 18.4%), atopic cough (AC) (188/1,311, 14.3%), and non-asthmatic eosinophilic bronchitis (NAEB) (147/1,311, 11.2%) were the common causes of chronic cough in descending order. The post-infectious cough (PIC) (39/1,311, 3.0%) and angiotensin-converting enzyme inhibitor (ACEI)-induced cough (25/1,311, 1.9%) were less common. During the 8-year period, the proportion of CVA (χ²=72.86, P<0.0001) and UACS/PNDs (χ²=68.80, P<0.0001) decreased, while those of NAEB (χ²=51.38, P<0.0001), GERC (χ²=55.95, P<0.0001) and AC (χ²=39.09, P<0.0001) increased.

Conclusions

The etiological frequency of chronic cough varies over time, and it may encourage the adjustment of the current diagnostic and therapeutic strategies for chronic cough.

Efficacy of sequential three-step empirical therapy for chronic cough

Background:

Empirical three-step therapy has been proved in just one hospital. This study aimed to demonstrate applicability of the sequential empirical three-step therapy for chronic cough in different clinical settings.

Methods:

Sequential empirical three-step therapy was given to patients with chronic cough in one tertiary and three secondary care respiratory clinics. Recruiters were initially treated with methoxyphenamine compound as the first-step therapy, followed by corticosteroids as the second-step therapy and the combination of a proton-pump inhibitor and a prokinetic agent as the third-step therapy. The efficacy of the therapy was verified according to the changes in cough symptom score between pre- and post-treatment, and compared among the different clinics.

Results:

In total 155 patients in one tertiary clinic and 193 patients in secondary care clinics were recruited. The total dropout ratio is significantly higher in the secondary care clinics than that in the tertiary clinic (9.3% versus 3.2%, p = 0.023). The therapeutic success rate for cough was 38.7% at first-step therapy, 32.3% at second-step therapy and 20.0% at third-step therapy in the tertiary clinic, and comparable to corresponding 49.7%, 31.1% and 4.1% in secondary care clinics. Furthermore, the overall cough resolution rate was not significantly different (91.0% versus 85.0%, p = 0.091). However, the efficacy of the third-step therapy is much higher (20.0% versus 4.1%, p = 0.001) in the tertiary clinic than in the secondary care clinics.

Conclusions:

Sequential empirical three-step therapy is universally efficacious and useful for management of chronic cough in different clinical settings.

Comparison of clinical characteristics of chronic cough due to non-acid and acid gastroesophageal reflux

BACKGROUND AND OBJECTIVE

Little is known about non-acid gastroesophageal reflux-induced chronic cough (GERC). The purpose of the study is to explore the clinical characteristics of non-acid GERC.

METHODS

Clinical symptoms, cough symptom score, capsaicin cough sensitivity, gastroesophageal reflux diagnostic questionnaire (GerdQ) score, findings of multichannel intraluminal impedance-pH monitoring (MII-pH) and response to pharmacological anti-reflux therapy were retrospectively reviewed in 38 patients with non-acid GERC and compared with those of 49 patients with acid GERC.

RESULTS

Non-acid GERC had the similar cough character, cough symptom score, and capsaicin cough sensitivity to acid GERC. However, non-acid GERC had less frequent regurgitation (15.8% vs 57.1%, χ(2)  = 13.346, P = 0.000) and heartburn (7.9% vs 32.7%, χ(2)  = 7.686, P  = 0.006), and lower GerdQ score (7.4 ± 1.4 vs 10.6 ± 2.1, t = -6.700, P = 0.003) than acid GERC. Moreover, MII-pH revealed more weakly acidic reflux episodes, gas reflux episodes and a higher symptom association probability (SAP) for non-acid reflux but lower DeMeester score, acidic reflux episodes and SAP for acid reflux in non-acid GERC than in acid GERC. Non-acid GERC usually responded to the standard anti-reflux therapy but with delayed cough resolution or attenuation when compared with acid GERC. Fewer patients with non-acid GERC needed an augmented acid suppressive therapy or treatment with baclofen.

CONCLUSIONS

There are some differences in the clinical manifestations between non-acid and acid GERC, but MII-pH is essential to diagnose non-acid GERC.

Capsaicin-sensitive cough receptors in lower airway are responsible for cough hypersensitivity in patients with upper airway cough syndrome

Background

Cough hypersensitivity may be related to the pathogenesis of upper airway cough syndrome (UACS). The purpose of the study was to investigate the role of capsaicin-sensitive cough receptors on the laryngopharynx and lower airway in the cough hypersensitivity of patients with UACS.

Material/Methods

59 patients with UACS, 33 patients with rhinitis/sinusitis without cough, and 39 healthy volunteers were recruited for the study. Cough threshold C5, defined as the lowest concentration of capsaicin required for the induction of ≥5 coughs upon esposure to capsaicin, were determined at baseline and after laryngopharngeal anesthesia with lidocaine in all the subjects. After induced sputum cytology, the concentrations of histamine, prostaglandin E2 (PGE2), and calcitonin-gene-related peptide (CGPR) in the induced sputum were measured by ELISA. In 15 patients with UACS, sputum cytology and measurement of the above mediators were repeated after successful therapy.

Results

C5 response to capsaicin was significantly lower in the UACS group than in the rhinitis/sinusitis group and healthy control groups [3.9 (0.98, 7.8) μmol/L vs. 7.8 (3.9, 93.75) μmol/L vs. 31.2 (15.6, 62.5) μmol/L, H=40.12, P=0.000]. Laryngopharngeal anesthesia with lidocaine dramatically increased C5 to capsaicin in the subjects of all 3 groups by a similar degree, but the increase in the UACS group was still the lowest, with an increased level of histamine, PGE2, and CGRP in the induced sputum. When cough resolved with the treatment of cetirizine alone or in combination with erythromycin, the levels of CGRP and histamine in the induced sputum decreased significantly in 15 patients with UACS, with no obvious change in cell differential or concentration of PGE2 in the induced sputum.

Conclusions

Laryngeal TRPV1 plays an important role in cough sensitivity, but sensitization of capsaicin-sensitive cough receptors in the lower airway may be more responsible for the cough hypersensitivity in patients with UACS.

Therapeutic efficacy of baclofen in refractory gastroesophageal reflux-induced chronic cough

AIM: To evaluate the efficacy and safety of baclofen for treatment of refractory gastroesophageal reflux-induced chronic cough (GERC) unresponsive to standard anti-reflux therapy.

METHODS: Sixteen patients with refractory GERC were given an 8-wk course of baclofen 20 mg three times a day as an add-on therapy to omeprazole. Changes in the cough symptom score, cough threshold to capsaicin, reflux symptom score and possible adverse effects were determined after treatment. The variables of multi-channel intraluminal impedance combined with pH monitoring were compared between responders and non-responders to baclofen.

RESULTS: Twelve of 16 patients completed treatment. Cough disappeared or improved in 56.3% (9/16) of patients, including 6 patients with acid reflux-induced cough (66.7%) and 3 patients with non-acid reflux-induced cough (33.3%). With baclofen treatment, the cough symptom score began to decrease at week 2, was clearly decreased at week 6 and reached a minimum at week 8. At the end of therapy, the lowest concentration of capsaicin required for induction of ≥ 2 and ≥ 5 coughs increased from 0.98 (1.46) to 1.95 (6.82) μmol/L (Z = -2.281, P = 0.024) and from 1.95 (7.31) to 7.8 (13.65) μmol/L (Z = -2.433, P = 0.014), respectively, and the reflux symptom score decreased from 8.0 ± 1.6 to 6.8 ± 0.8 (t = 2.454, P = 0.023). The number of acid reflux episodes was significantly lower in responders than in non-responders. The main adverse effects were somnolence, dizziness and fatigue.

CONCLUSION: Baclofen is a useful, but suboptimal treatment option for refractory GERC.

Occupational asthma: review of assessment, treatment, and compensation

Occupational asthma refers to asthma induced by exposure in the working environment to airborne dusts, vapors, or fumes, with or without preexisting asthma. Potential triggers of occupational asthma are diverse and involve a variety of postulated mechanisms. After confirming the presence of asthma, diagnosis hinges on obtaining a detailed and accurate occupational and environmental history and documenting a temporal association of symptoms or signs with workplace exposure. Management of occupational asthma centers on prescribing standard asthma therapies in conjunction with instituting preventive strategies, such as appropriate avoidance of environmental triggers, providing work restrictions, and using environmental controls and/or personal respiratory protection. If a worker is determined to be ill or injured, there are a variety of compensation systems that are designed to protect workers financially from disability related to respiratory impairments; however, the administrative process is frequently difficult to navigate for patients and their providers. Focusing on obtaining a detailed occupational and environmental history, establishing clear objective data to substantiate illness, and estimating or apportioning workplace contribution to the condition is important for the diagnosis and treatment of this relatively common form of asthma.