RESUMO
INTRODUCTION: The 24-hours pH-monitoring is the "gold standard" to verify the presence of pathologic reflux and confirmation of GERD. But there is lack of data whether it is helpful to verify the link between extraesophageal manifestations with GERD. AIM: To evaluate the utility of proximal 24-hours pH monitoring for diagnosing ENR manifestations of GERD. METHODS: Ninety one GERD patients were enrolled to the study. The allergic, infectious and toxic etiology of comorbid diseases were exclusion criteria. Dual-probe 24-hours pH studies were performed to all of the patients. Distal probe was placed 5 cm above esophago-gastric junction, the proximal one--at the upper 1/3 of esophagus over upper esophageal sphincter. The presence of high gastroesophageal reflux (HGR) was diagnosed when at least one episode of drop of pH < 4 for 20 sec at proximal probe during the study occurred. The evaluation of sensitivity and specificity of the method was calculated by the standard protocol. RESULTS: Comorbid ENR pathology (GERD + CP) was found in 59 patients. Presence of HGR was found in 76.27% of patients of GERD + CP group and in 43.75% of controls (p = 0.0026). Number of HGR was higher in GERD + CP group: M +/- s: 12.51 +/- 18.56 compared to 2.84 +/- 7.11 accordingly, p = 0.0003. Mean pH values were lower in the main group: 6.32 +/- 0.52 compared to 6.58 +/- 0.42 in controls, p = 0.011. Acid exposure time was greater in the main group: 3.19 +/- 6.76 min, compared to 2.42 +/- 10.02 min in controls, p = 0.003. The correlation was found between each of the studied pH-metric parameters and presence of ENR pathology in GERD patients. The results of calculated diagnostic efficacy of the 24-hrs pH monitoring for evaluating the link between GERD and comorbid pathology were as follows: Diagnostic sensitivity--76.27% (95% Confidence Interval's limits (CI): 0.6403-0.8531); Diagnostic specificity: 56.25% (95% CI [0.3933-0.7183]); likelihood ratio for a positive test result 1.743 (95% CI [1.148-2.648]); likelihood ratio for a negative test result 0.422 (95% CI [0.243-0.731]). CONCLUSION: There is correlation between parameters of 24-hours pH-monitoring in the proximal esophagus and comorbid ENR pathology in GERD patients. High gastroesophageal reflux is more common in GERD patients with comorbid ENR pathology than in GERD patients without ENR diseases. Detection of high gastroesophageal reflux with placing the distal probe in the upper esophagus may be helpful for the diagnosing of extraesophageal manifestations of GERD.
