Sensitive pepsin immunoassay for detection of laryngopharyngeal reflux

OBJECTIVES/HYPOTHESIS: To determine whether measurement of pepsin in throat sputum by immunoassay could be used as a sensitive and reliable method for detecting laryngopharyngeal reflux (LPR) compared with 24-hour double-probe (esophageal and pharyngeal) pH monitoring. STUDY DESIGN: Patients with clinical LPR undergoing pH monitoring provided throat sputum samples during the reflux-testing period for pepsin measurement using enzyme-linked immunoadsorbent assay. RESULTS: Pepsin assay results from 63 throat sputum samples obtained from 23 study subjects were compared with their pH monitoring data. Twenty-two percent (14/63) of the sputum samples correlated the presence of pepsin with LPR (pH < or = 4 at the pharyngeal probe), of which the median concentration of pepsin was 0.18 microg/mL (range 0.003-22 microg/mL). Seventy-eight percent (49/63) of the samples unassociated with (pharyngeal) reflux contained no detectible pepsin. Mean pH values for pepsin-positive samples were significantly lower than negative samples at both esophageal probe (pH 2.2 vs. pH 5.0) (P < .01) and the pharyngeal probe (pH 4.4 vs. pH 5.8) (P < .01). When the pepsin assay results were compared with the pharyngeal pH data for detecting reflux (events pH < or = 4), the pepsin immunoassay was 100% sensitive and 89% specific for LPR. CONCLUSIONS: Detection of pepsin in throat sputum by immunoassay appears to provide a sensitive, noninvasive method to detect LPR.     

Effects of pepsin A on heat shock protein 70 response in laryngopharyngeal reflux patients with chronic rhinosinusitis

Objectives: We investigated the relationship between laryngopharyngeal reflux (LPR) and chronic rhinosinusitis (CRS), and explored the effects of pepsin A on the level of heat shock protein 70 (HSP70) in CRS.

Methods: We included 23 CRS patients with nasal polyps (CRSwNP), 26 CRS patients without nasal polyps (CRSsNP) and nine normal controls to measure pepsin A levels in nasal secretions, blood plasma and nasal tissues, to measure HSP70 levels in nasal tissues, and to detect pepsinogen A, HSPA5, cyclo-oxygenase-2 (COX-2), and carbonic anhydrase III (CAIII) mRNA expression levels in nasal tissues.

Results: Pepsin A levels in nasal secretions were significantly higher in CRSwNP/CRSsNP patients than in controls. HSP70 levels were significantly increased in pepsin A-positive turbinate mucosa compared to controls (p?p?=?.016). Furthermore, no association was found between the presence of pepsin A and HSPA5, COX-2, and CAIII mRNA expression levels.

Conclusions: These results suggest that LPR may play a role in the development of CRS through pepsin A reflux, and increased HSP70 expression may be associated with the pathogenic mechanism of mucosal injury in CRS.     

Clinical evaluation of pepsin for laryngopharyngeal reflux in children with otitis media with effusion

Objective

We sought to evaluate the clinical role of pepsin for laryngopharyngeal reflux (LPR) in children with otitis media with effusion (OME).

Methods

Pepsin/pepsinogen and fibrinogen were analyzed in fifty effusion and blood samples of children with OME using enzyme linked immunosorbent assay (ELISA). Ambulatory 24-h dual-probe pH monitoring was additionally performed in 31 children divided into two groups according to response of medical treatment.

Results

The effusion levels of pepsin/pepsinogen ranged from 8.5 to 1512 μg/dl and were up to 4–540 times higher than the concentrations found in plasma samples. The effusion levels of fibrinogen ranged from 0.05 to 4.1 g/dl. Some effusion samples showed fibrinogen concentrations did not exceed 10 times higher than the concentrations found in plasma samples and others showed lower concentrations. The pH of effusion samples was 7.13 to 8.72. Dual-probe pH monitoring showed that 22/31 (71%) of the studied children had significant acid reflux documented by either the esophageal probe or the pharyngeal probe and all of them had LPR. There is a significant positive correlation between the level of pepsin assayed in the effusions and the number of pharyngeal reflux episodes measured by pH monitoring.

Conclusions

Analysis of pepsin/pepsinogen in effusion samples of children with OME, using ELISA, can be considered as a reliable biochemical marker for assessment of laryngopharyngeal reflux.     

Laryngeal pseudosulcus as a predictor of laryngopharyngeal reflux.

OBJECTIVES/HYPOTHESIS: Laryngeal pseudosulcus is an accurate prognostic indicator of laryngopharyngeal reflux (LPR) disease. STUDY DESIGN: Prospective study of 20 consecutive patients with laryngeal pseudosulcus. Pseudosulcus is infraglottic laryngeal edema that is thought to be secondary to LPR. All patients were evaluated with dual-channel pH probe 24-hour monitoring to evaluate for the presence of laryngopharyngeal reflux. METHODS: Twenty patients identified with laryngeal pseudosulcus on routine physical examination were included in the study. Each patient underwent a 24-hour dual-channel pH probe. The data were analyzed and compared with previously published normative data. The data included the total number of reflux episodes and the percentage of time the pH dropped below 4 at the proximal probe. RESULTS: Eighteen of the 20 patients with laryngeal pseudosulcus were found to have LPR. The mean number of reflux episodes at the proximal probe was 29.4 (range, 3-82). The mean percentage of time the pH dropped below 4 was 1.15%. In the upright position the mean value was 1.59% and in the supine position it was 0.19%. This gives pseudosulcus a positive predictive value for LPR of 90%. CONCLUSION: This study shows laryngeal pseudosulcus to be an accurate predictor of laryngopharyngeal reflux disease.     

慢性咽炎患者喉咽反流分析

目的 探讨慢性咽炎与喉咽反流(laryngopharyngeal reflux,LPR)发生的关系.方法 对112例慢性咽炎患者行24小时双探头(食管和咽部)pH值监测,将检查出的62例LPR患者随机分为两组,实验组:应用抑制胃酸药和清热解毒的咽炎药治疗;对照组:单用清热解毒的咽炎药,对两组咽部症状缓解及病变改善情况进行统计学比较.结果 慢性咽炎的体征多样化,实验组35例,有效率94.29%(33例),对照组27例,有效率77.78%(21例),P＜0.05.结论 LPR是导致慢性咽炎的重要病因,使用抑酸剂可明显改善喉咽反流,从而达到治疗慢性咽炎的目的.     

Association of nasopharyngeal and laryngopharyngeal reflux with postnasal drip symptomatology in patients with and without rhinosinusitis

BACKGROUND: Patients often report postnasal drip (PND), but objective rhinosinusitis and allergy findings are frequently absent. In this study, we evaluate the association between PND and pharyngeal reflux. METHODS: Sixty-eight participants underwent 24-hour pH testing, including chronic rhinosinusitis (CRS) patients persistently symptomatic after endoscopic sinus surgery, CRS patients successfully treated by endoscopic sinus surgery, and volunteers without a CRS history. The pH probes contained nasopharyngeal (NP), laryngopharyngeal (LP), and distal esophageal sensors. Participants completed the Sinonasal Outcome Test-20 (SNOT-20) and Modified Reflux Symptom Index (MRSI) questionnaires. Survey items addressing PND symptomatology were compared with NP reflux (NPR) below pH 4 and pH 5 (defined as > or = 1 event), and LP reflux (LPR; defined as > or = 7 events or reflux area index > 6.3). RESULTS: Pearson analyses revealed a positive correlation of r = 0.87 between SNOT-20 and MRSI PND items. For NPR < pH 4, no significant difference existed between participants with and without reflux on the SNOT-20 or MRSI (p > 0.05). However, for NPR < pH 5, reflux-positive participants exhibited significantly more PND symptoms on the SNOT-20 (p = 0.030) and the MRSI (p = 0.018) compared with participants without reflux. Finally, participants with LPR had significantly more PND symptomatology on the SNOT-20 (p = 0.010) versus those without LPR. A borderline significant difference existed on the MRSI PND item between participants positive and negative for LPR (p = 0.055). CONCLUSION: Objective evidence of NPR and LPR exists in patients reporting PND. Reflux treatment may reduce PND complaints.     

Esophageal motor function in laryngopharyngeal reflux is superior to that in classic gastroesophageal reflux disease.

Laryngopharyngeal reflux (LPR) in otolaryngology patients appears to be different from classic gastroesophageal reflux disease (GERD). In particular, esophagitis and its principal symptom, heartburn, considered the diagnostic sine qua non of GERD, are often absent in LPR. It has therefore been postulated that LPR patients have superior esophageal function. Esophageal acid clearance (EAC) is a measure of the ability of the esophagus to restore neutral pH after reflux events have occurred. It is considered an excellent overall measure of esophageal function. The mean EAC can be calculated from 24-hour pH monitoring data. A comparison of EAC in patients with GERD and LPR has not been previously reported. To compare the EAC of 1) patients with LPR alone, 2) patients with GERD alone, 3) patients with both LPR and GERD, and 4) patients without either LPR or GERD, we studied 200 otolaryngological patients who had undergone 24-hour double-probe (simultaneous pharyngeal and distal esophageal) pH monitoring, 50 in each group. The subgrouping of each patient was determined by previously established pH monitoring criteria. We defined GERD as abnormal esophageal reflux and LPR as abnormal pharyngeal reflux. The patients with GERD had a mean (+/-SD) EAC of 1.44 +/- 1.2 minutes, and those with LPR had a mean EAC of 1.00 +/- 1.00 minutes (p < .05). The patients with both GERD and LPR had a mean EAC of 1.53 +/- 1.01 minutes. The patients without reflux had a mean EAC of 0.53 +/- 0.38 minutes. We conclude that patients with LPR have significantly better EAC than those with GERD. These data suggest that patients with LPR have superior esophageal function. This finding may clarify our understanding of the differences in mechanisms, symptoms, and incidence of esophagitis in patients with LPR and GERD.     

The role of laryngopharyngeal reflux as a risk factor in laryngeal cancer: a preliminary report

Objectives

To evaluate the significance of laryngopharyngeal reflux (LPR) as a risk factor in laryngeal cancer.

Methods

We performed a case-control study with 29 consecutive laryngeal cancer patients who had undergone 24-hour ambulatory double pH monitoring from 2003 to 2006. The control group included 300 patients who had undergone 24-hour ambulatory double pH monitoring due to LPR-related symptoms. We analyzed the prevalence of LPR and numerous parameters from the 24-hour ambulatory double pH monitoring in the laryngeal cancer patient and control groups. Pathologic LPR is defined when more than three episodes of LPR occur in 24 hours.

Results

The prevalence of pathologic LPR was significantly higher in the laryngeal cancer group than the control group (P=0.049). The reflux number of the upper probe was significantly higher in the laryngeal cancer group (P<0.001). However the effects of pathologic LPR on laryngeal cancer risk were diluted after adjusting for smoking and alcohol consumption in the multivariable logistic regression.

Conclusion

The pathologic LPR might be a possible risk factor in the development of laryngeal cancer. A further study should be necessary to verify the exact role of LPR in laryngeal cancer.     

Dx-pH监测与胃蛋白酶反流试纸条在咽喉反流诊断中的一致性分析

目的分析胃蛋白酶试纸条、Dx-pH监测及RSI（reflux symptom index）与RFS（reflux finding score）量表在咽喉反流性疾病(LPRD)中的一致性。方法回顾性分析2017年8月—2019年2月就诊于解放军总医院第六医学中心耳鼻咽喉科的110例喉科疾病住院患者的临床资料,记录患者的RSI和RSF两类量表的评分数值、Dx pH监测后的Ryan指数, 胃蛋白酶试纸盒的检测结果,用Kappa分析三者间的相关性。结果110例患者中胃蛋白酶反流检测阳性75例,阴性35例,阳性率68.18%;Dx pH检测阳性率22.73%（25/110）,两者间诊断一致率为41.82%;RSI、RFS量表诊断LPRD阳性率90%（99/110）, 与胃蛋白酶反流检测一致率74.55%;且两者间一致性较高（k=0.324）。以Dx-pH监测为参考标准,胃蛋白酶检测的敏感度为72.00% (18/25)、特异度为32.94% (28/85);以RSI、RFS量表诊断为参考标准,敏感度73.73%,特异度为81.82%, 阳性预测值为97.33%。结论RSI、RSF评分与胃蛋白酶反流试纸条结果间的一致性相较于其他检查更高,胃蛋白酶反流试纸虽然不能成为诊断咽喉反流性疾病的金标准,但是作为一项新的无创诊断技术之一, 可以联合Dx pH监测及RSI、RFS量表广泛应用于临床。     

Is laryngopharyngeal reflux related to functional dysphonia?

OBJECTIVES: Laryngopharyngeal reflux (LPR) may be a contributing factor in chronic hoarseness. The association of LPR with functional dysphonia (FD), the most common voice clinic diagnosis, is unknown. We attempted to determine whether patients with FD have a higher rate of laryngeal exposure to acidic stomach contents than do healthy volunteers. METHODS: We recruited through the voice clinic 23 patients who had had persistent dysphonia for 3 months. Pregnancy, major structural laryngeal abnormality, and vocal fold paralysis were exclusion criteria. Eight healthy volunteers were recruited. The subjects gave informed consent to enter the study, which had the approval of our hospital ethics committee. The patients and control subjects underwent 24-hour dual-probe pH-metry. RESULTS: Twenty-two patients and 6 control subjects completed the study. Overall, there seemed to be no statistical differences between patients and controls on all but 2 channel 1 pH-metry parameters. These were the longest reflux episode (seconds) in a supine position, and the fraction of time the pH was less than 4 in a supine position. Both of these time periods were longer in patients than in the controls (p < .05). CONCLUSIONS: Our study demonstrated an association between LPR and FD for 2 pH parameters. Larger studies are required to assess the potential relationship between nonorganic dysphonias and reflux. Furthermore, the presence of a multifactorial causation of FD, including "medical" and psychological causes, should be addressed in future studies.     

Therapiekontrolle bei laryngopharyngealem Reflux durch wiederholte 2-Kanal-pH-Metrie

Objectives

The most effective current treatment option for patients suffering from laryngopharyngeal reflux (LPR) is the use of proton pump inhibitors (PPIs). Compared to other PPIs, esomeprazole seems to provide best 24-h control of intragastric acid. However, some patients remain resistant to medical acid suppression with PPIs. The aim of this investigation was to identify the number of non-responders among patients suffering from LPR being treated by esomeprazole 40 mg once daily (officially approved maximum dosage).

Patients and methods

Between June 2004 and January 2006, 27 patients suffering from LPR diagnosed by dual-probe pH monitoring were treated with esomeprazole 40 mg once daily. After 13–54 days (mean 28 days) while still under PPI-treatment, the 24-h pH-study was repeated in order to control the effectiveness of therapy. Patients with at least a reduction of the reflux area index (RAI) compared to the result before treatment were categorized as responders. Furthermore, the number of patients with a measurable reduction of proximal reflux episodes under PPI-treatment was quantified.

Results

Repeated pH monitoring during PPI therapy revealed a reduction of the RAI in 22 of 27 patients. Five patients, however, showed a higher RAI despite medical treatment (19%). In 13 patients (48%), treatment with 40 mg esomeprazole once daily reduced the RAI to a normal value (<6.3). In 18 of 27 patients, the number of proximal reflux episodes has decreased (67%).

Conclusion

In a number of patients suffering from LPR, treatment with esomeprazole 40 mg once daily did not provide any measurable proximal acid reduction. Repeated pH monitoring during treatment is an adequate diagnostic tool to control the therapeutic effect of PPIs objectively and to identify non-responders at an early point.     

Dual-probe 24-hour ambulatory pH monitoring for diagnosis of laryngopharyngeal reflux

BACKGROUND: Patients with gastroesophageal reflux disease may suffer from a variety of symptoms from the upper aerodigestive tract. The objective of this study was to determine the impact of dual-probe 24-hr pH monitoring in the diagnosis of reflux-related otolaryngological disorders. METHODS: Twenty-two patients with symptoms such as chronic cough, globus pharyngeus, heartburn, dysphonia and burning sensation of the tongue underwent a complete ear, nose and throat examination, 24-hr dual-probe pH monitoring, and oesophago-gastro-duodenoscopy. RESULTS: pH monitoring revealed gastroesophageal (distal) reflux in all patients and pharyngeal (proximal) reflux in 21 patients. Treatment consisted of a proton pump inhibitor (esomeprazole). Within 4 weeks 68 per cent of patients had no laryngopharyngeal symptoms; within 8 weeks 95 per cent of patients were symptom-free. CONCLUSIONS: Patients with atypical reflux symptoms such as hoarseness, globus sensation or throat-clearing responded well to anti-reflux treatment.     

Is laryngopharyngeal reflux an important risk factor in the development of laryngeal carcinoma?

Laryngopharyngeal reflux (LPR) as a causative irritating factor in the development of laryngeal carcinoma has been suggested. However, the association between LPR and laryngeal carcinoma remains unclear. The aim of this study was to compare the prevalence and severity of reflux between patients with laryngeal carcinoma and clinical LPR. The intention was to find out if a correlation exists between the laryngeal findings and the level of acid reflux. The study population consisted of 29 patients with laryngeal cancer (group I), 33 LPR patients with normal laryngeal findings (group II) and 70 LPR patients with related laryngeal pathology (group III). The results of 24-h, double-channel ambulatory esophageal pH monitoring were analyzed comparing the three groups. The occurrence and severity of abnormal acid reflux at the upper and lower esophageal segments were evaluated. The incidence of LPR or gastroesophageal reflux (GER) did not vary in any of the three groups (LPR was present in 62, 42 and 56% of the patients, while GER was present in 45, 24 and 37% of the patients, respectively). Patients with LPR or GER from the three groups did not differ significantly in terms of the number of acid reflux episodes and percentage of times when the pH was <4. Our data do not support the hypothesis that LPR can be an independent risk factor in the development of larynx cancers. However, the data also do not thoroughly exclude the possibility. The reason why LPR leads to variable pathologies in the larynx may be uncovered by studies probing the differences between patients via detailed examinations of the local anti-reflux barriers such as epithelial morphology and functions.     

全天咽喉pH检测在诊断反流性咽喉部疾病中的作用

目的探讨24h咽喉pH检测在咽喉反流性疾病诊断中的价值。方法选取2006年8月至10月于北京同仁医院就诊由同一医师诊断可疑有反流性咽喉炎患者50例，征得患者同意后以就诊时间为配伍因素，按区组随机排列方法采用半随机分组。第一组25例患者均行24h咽喉pH检测，筛选出阳性患者作为试验组接受奥美拉唑抗酸治疗；第二组25例患者直接给予相同药物及剂量的试验性抗酸治疗作为对照组。服药3个月后进行随访，根据反流症状评分对比治疗前后效果，以主观症状评估总分下降≤4分为治疗无效，〉4分为有效。结果行24h咽喉pH检测的25例患者中有病理性咽喉部反流者17例，阳性率为68.0％（17／25）。24h平均总反流次数（35．71±41．70）次（x±s，以下同），总反流时间（35．71±33．19）min，总反流指数即每小时反流次数（1．53±1．73）次／h，每次反流平均时间（1．12±0．91）min。抗酸治疗前试验组症状评估总分平均（14．88±4．11）分，对照组总分平均（13．00±4．17）分，组间差异采用t检验，无统计学意义（P〉0．05）。在抗酸治疗3个月后随访，试验组有效率为82．4％（14／17），对照组失访2例，其余患者治疗有效率为52．2％（12／23）。试验组症状评估总分平均下降（7．47±3．18）分，对照组症状评估总分下降（3．96±4．25）分，总分差值比较，差异有统计学意义（P〈0．01）。结论24h咽喉pH检测作为诊断咽喉反流性疾病的金标准，可以作为临床中可疑咽喉反流患者的确诊检查手段，并可大大提高抗酸治疗的有效性，值得在临床普遍开展和推广。     

The key timing of pharyngeal reflux in patients with laryngopharyngeal reflux

ObjectiveTo analyze the incidence of pharyngeal reflux in laryngopharyngeal reflux patients over a 24-hour period and find out the key timing of pharyngeal reflux.MethodsWe reviewed 69 patients who visited our clinic with LPR-related symptoms and were proven to have pharyngeal reflux via 24‐hour multichannel intraluminal impedance‐pH (24hr MII‐pH) monitoring. Quantitative analysis was conducted for the LPR profiles, such as the acidity of reflux, nighttime reflux, and positional reflux. The time series of pharyngeal reflux episodes and mealtimes were analyzed over a 24-hour period. Also, we recruited 26 normal controls. We compared the timing of pharyngeal reflux between LPR patients and asymptomatic controls.ResultsThe quantitative analysis revealed that pharyngeal reflux occurred 4.88 ± 4.59 times over 24 hours. Weakly acidic pharyngeal reflux was more abundant than acidic or weakly alkaline reflux. Pharyngeal reflux occurred mainly during daytime in the upright position. The most frequent timing of pharyngeal reflux episodes was within 2 hours after meals. Additionally, there was no significant difference of the timing of post-prandial reflux between LPR patients and asymptomatic controls.ConclusionThe key timing of pharyngeal reflux in patients with LPR was post-prandial 2 hours.     

Review of management of laryngopharyngeal reflux disease

This review was conducted according to the Patient/problem Intervention Comparison Outcome (PICO) Statements. Some studies reported that 10–30% of patients consulting in ENT come with presenting symptoms of laryngopharyngeal reflux (LPR), but the exact prevalence of LPR is still unknown. Management has not changed in 20 years despite a significant increase in the number of publications on epidemiology, clinical presentation, diagnosis and treatment. The development of hypopharyngeal-esophageal multichannel intraluminal impedance pH monitoring (HEMII-pH) and saliva pepsin detection now allow a new multidimensional diagnostic approach associating clinical scores to HEMII-pH and saliva pepsin detection. This new approach may enable personalized treatment according to LPR profile on HEMII-pH (acid, non-acid, mixed; upright, recumbent reflux episodes). Updated treatment of LPR could consist in a 3-month association of dietary measures, proton pump inhibitors, alginate and magaldrate, followed by treatment adaptation.     

The comparison of an empiric proton pump inhibitor trial vs 24-hour double-probe Ph monitoring in laryngopharyngeal reflux

Laryngopharyngeal reflux (LPR), which is defined as the backflow of gastric contents into the upper aerodigestive tract, is a relatively common disorder. However, its diagnosis still poses many problems. Twenty-four-hour double-probe pH monitoring is currently the diagnostic test of choice, but it has many disadvantages. Thus, an empiric trial of antireflux therapy has been suggested as an alternative method for diagnosis. The purpose of this article is to evaluate the validity of this alternative method in the management of LPR. The study group consisted of 36 patients with symptoms and physical findings suggesting LPR. The control subjects were 23 healthy adults. Twenty-four-hour double-probe pH monitoring was performed both in the study group and the control group, and the results were compared. In addition, the symptoms and physical findings in the study group was scored by the modified reflux symptom index (MRSI) and reflux finding score (RFS) at four intervals: before the start of therapy and at the second, fourth and sixth months of the therapy. The results of the 24-hour double-probe pH monitoring showed no significant difference between the study and the control groups (p>0.05). In the study group, the MRSI before the therapy was 13.6+/-4.4. This index improved significantly to 4.3+/-1.9 at the second month; to 1.5+/-0.6 at the fourth month, and to 0.5+/-0.2 at the sixth month of the therapy (p<0.05). The RFS before the start of the therapy was 14.8+/-3.8; and it improved significantly to 7.7+/-3.8 at the second month; to 4.5+/-2.3 at the fourth month, and to 1.4+/-0.9 at the sixth month of the therapy (p<0.05). The significant improvement in the MRSI and the RFS during the course of proton pump inhibitor therapy relates the patients' symptoms and physical findings to LPR. This implies the validity of the method, not only in the treatment of LPR, but in the diagnosis of this disorder, as well. Unfortunately, 24-hour double-probe pH monitoring has failed to differentiate LPR patients from healthy individuals.     

Prevalence of pH-documented laryngopharyngeal reflux in Chinese patients with clinically suspected reflux laryngitis

PURPOSE: Laryngopharyngeal reflux (LPR) is one of the main factors behind different laryngeal pathology according to the Western literature. Literature reported that the prevalence of gastroesophageal reflux disease (GERD) in Chinese population was considerably lower than that in Western countries. To date, however, there is no study to evaluate the prevalence of pH-documented LPR in the Chinese ethnicity. MATERIALS AND METHODS: We thus recruited 28 consecutive Chinese patients with reflux symptoms including globus, throat discomfort, throat clearing, chronic cough, or burping lasting more than 1 month in the preceding 1 year, together with stroboscopic evidence suggestive of reflux laryngitis according to the reflux finding score in our study. All patients underwent thorough head and neck examination and transnasal endoscopic assessment. The prevalence of pH-documented LPR and GERD was then documented using ambulatory 24-hour pH biprobe study. RESULTS: Six (21%) of the 28 patients had pH-documented LPR. Four (14%) of the 28 patients had GERD with 3 of them having concomitant LPR. Only burping was associated with pH-documented LPR (P < .05). No relationship was observed between pH-documented LPR and other factors, including age, sex, other reflux symptoms except burping, and the reflux finding score. CONCLUSION: Chinese patients do have and present with symptoms of extraesophageal reflux, and we observed a lower prevalence of pH-documented LPR in Chinese patients with clinically suspected reflux laryngitis compared with white patients.     

Meta-analysis of upper probe measurements in normal subjects and patients with laryngopharyngeal reflux

We report a meta-analysis of a series of studies in which 24-hour ambulatory pH monitoring was performed in 1) normal subjects, 2) the normal control subjects in studies of laryngopharyngeal reflux (LPR), and 3) the patients with LPR in these controlled studies. The statistical analysis utilized the fixed-effects model by Mantel-Haenszel and the random-effects mixed model. There were 16 studies from the past 12 years that fulfilled the inclusion criteria. They involved 793 subjects (264 normal and 529 with LPR). The numbers of positive pharyngeal reflux events for normal subjects and for patients with LPR differed with a p value of <.0001. There was also a significant difference in the mean percentage of acid exposure times between normal subjects and patients with LPR (p = .003). We conclude that the upper probe gives accurate and consistent information in normal subjects and patients with LPR. The numbers of reflux events and acid exposure times are most important in distinguishing normal subjects from patients with LPR. The technology and methodology of probe testing is quite reliable and is consistent on a worldwide basis.