Mean nocturnal baseline impedance in gastro-esophageal reflux disease diagnosis:Should we strictly follow the Lyon 2 Consensus?

Clinical practice guidelines drive clinical practice and clinicians rely to them when trying to answer their most common questions.One of the most important position papers in the field of gastro-esophageal reflux disease(GERD)is the one produced by the Lyon Consensus.Recently an updated second version has been released.Mean nocturnal baseline impedance(MNBI)was proposed by the first Consensus to act as supportive evidence for GERD diagnosis.Originally a cut-off of 2292 Ohms was proposed,a value revised in the second edition.The updated Consensus recommended that an MNBI<1500 Ohms strongly suggests GERD while a value>2500 Ohms can be used to refute GERD.The proposed cut-offs move in the correct direction by diminishing the original cut-off,nevertheless they arise from a study of normal subjects where cut-offs were provided by measuring the mean value±2SD and not in symptomatic patients.However,data exist that even symptomatic patients with inconclusive disease or reflux hypersensitivity(RH)show lower MNBI values in comparison to normal subjects or patients with functional heartburn(FH).Moreover,according to the data,MNBI,even among symptomatic patients,is affected by age and body mass index.Also,various studies have proposed different cut-offs by using receiver operating characteristic curve analysis even lower than the one proposed.Finally,no information is given for patients submitted to on-proton pump inhibitors pH-impedance studies even if new and extremely important data now exist.Therefore,even if MNBI is an extremely important tool when trying to approach patients with reflux symptoms and could distinguish conclusive GERD from RH or FH,its values should be interpreted with caution.

Prevalence of gastroesophageal reflux disease in children with extraesophageal manifestations using combined-video,multichannel intraluminal impedance-pH study

BACKGROUND Gastroesophageal reflux disease(GERD)might be either a cause or comorbidity in children with extraesophageal problems especially as refractory respiratory symptoms,without any best methods or criterion for diagnosing it in children.AIM To evaluate the prevalence of extraesophageal GERD using conventional and combined-video,multichannel intraluminal impedance-pH(MII-pH),and to propose novel diagnostic parameters.METHODS The study was conducted among children suspected of extraesophageal GERD at King Chulalongkorn Memorial Hospital between 2019 and 2022.The children underwent conventional and/or combined-video MII-pH.The potential parameters were assessed and receiver operating characteristic was used for the significant parameters.RESULTS Of 51 patients(52.9%males),aged 2.24 years were recruited.The common problems were cough,recurrent pneumonia,and hypersecretion.Using MII-pH,35.3%of the children were diagnosed with GERD by reflux index(31.4%),total reflux events(3.9%),and symptom indices(9.8%)with higher symptom recorded in the GERD group(94 vs 171,P=0.033).In the video monitoring group(n=17),there were more symptoms recorded(120 vs 220,P=0.062)and more GERD(11.8%vs 29.4%,P=0.398)by symptom indices.Longest reflux time and mean nocturnal baseline impedance were significant parameters for diagnosis with receiver operating characteristic areas of 0.907(P=0.001)and 0.726(P=0.014).CONCLUSION The prevalence of extraesophageal GERD in children was not high as expected.The diagnostic yield of symptom indices increased using video monitoring.Long reflux time and mean nocturnal baseline impedance are novel parameters that should be integrated into the GERD diagnostic criteria in children.

Gastroesophageal reflux disease in pediatric esophageal atresia:Assessment of clinical symptoms and pH-impedance data

BACKGROUND Esophageal atresia(EA)is the most common congenital anomaly of the gastrointestinal tract.Gastroesophageal reflux disease(GERD)is a frequent and lifelong problem in these patients.GERD can be asymptomatic and the incidence of esophageal gastric and intestinal metaplasia(Barrett’s esophagus)is increased in adults with EA compared with the general population.Timely and accurate diagnosis of GERD is important to reduce long-term problems and this may be achieved by pH-impedance testing.AIM To assess symptoms and pH-impedance data in children after EA,in order to identify their specific features of GERD.METHODS This study was conducted from November 2017 to February 2020 and involved 37 children who had undergone EA via open surgical repair(51.35%boys,48.65%girls;age range:1-14 years,median:4.99 years).GERD diagnosis was made based on multichannel intraluminal impedance/pH study and two groups were established:EA without GERD,n=17;EA with GERD,n=20.A control group was established with 66 children with proven GERD(68.18%boys,31.82%girls;median age:7.21 years),composed of a nonerosive reflux disease(referred to as NERD)group(n=41)and a reflux esophagitis group(n=25).Upper gastrointestinal endoscopy with a mucosal esophageal biopsy was performed on all patients.RESULTS The most frequently observed symptom in EA patients with GERD and without GERD was cough(70%and 76.5%respectively).The number of patients with positive symptom association probability in the EA groups was significantly larger in the EA without GERD group(P=0.03).In the control reflux esophagitis group,prevalence of gastrointestinal symptoms was significantly higher than in the NERD group(P=0.017).For both EA groups,there was strong correlation with index of proximal events(IPE)and total proximal events(EA with GERD:0.96,P<0.001;EA without GERD:0.97,P<0.001)but level of IPE was significantly lower than in GERD patients without any surgical treatment(P<0.001).Data on distal mean nocturnal baseline impedance were significantly different between the EA with GERD group(P<0.001)and the two control groups but not between EA without GERD and the two control groups.CONCLUSION Mean nocturnal baseline impedance may have diagnostic value for GERD in EA children after open surgical repair.IPE might be an additional parameter of pHimpedance monitoring.