Breath 13CO2-evidence for a noninvasive biomarker to measure added refined sugar uptake.

Increased consumption of added sucrose and high-fructose corn syrup in the human diet has been associated with increasing incidence of obesity and metabolic disease. There are currently no reliable, objective biomarkers for added sugar intake that could be used in individuals or population settings. 13C is a stable isotope of carbon, and measurement of blood 13C content has been proposed as a marker of added sugar consumption. This study aimed to determine if breath 13CO2 could represent an alternative, noninvasive biomarker to monitor added sugar intake. We undertook retrospective analyses of eight preclinical and human 13C-breath studies to define baseline breath 13CO2 characteristics. All samples were analyzed using isotope ratio mass spectrometry, and breath 13CO2 was expressed as the delta value, δ expressed as parts per thousand (‰). All data are expressed as mean ± SEM, with statistical significance considered at P < 0.05. Breath δ13CO2 was significantly elevated in a cumulative manner in rats and mice that consumed a diet containing at least 15% sucrose. Mice fed an American rodent chow diet containing 50% sucrose and 15% corn starch had a significantly higher breath δ13CO2 compared with rodents consuming an Australian rodent chow diet. Furthermore, breath δ13CO2 was significantly increased in a dose-dependent manner in humans that ingested a bolus dose of sucrose. These findings suggest application for baseline breath δ13CO2 as a noninvasive biomarker for added sugar consumption, with broad application for longitudinal assessment of population sugar intake and obesity management strategies.NEW & NOTEWORTHY We have found that breath 13CO2 is increased in rats and mice consuming diets high in sucrose. We also found that human breath 13CO2 is increased in humans consuming increasing amounts of sucrose. Our collective findings suggest that breath 13CO2 represents a potential marker of added dietary sugar consumption.

Characterization of Upper Gastrointestinal Motility in Infants With Persistent Distress and Non-IgE-mediated Cow's Milk Protein Allergy.

BACKGROUND: Persistent crying in infancy is common and may be associated with gastroesophageal reflux disease (GERD) and/or non-IgE-mediated cow's milk protein allergy (CMPA). We aimed to document upper gastrointestinal motility events in infants with CMPA and compare these to findings in infants with functional GERD. METHODS: Infants aged 2 to 26 weeks with persistent crying, GERD symptoms and possible CMPA were included. Symptoms were recorded by 48-hour cry-fuss chart and validated reflux questionnaire (infant GERD questionnaire [IGERDQ]). Infants underwent a blinded milk elimination-challenge sequence to diagnose CMPA. GERD parameters and mucosal integrity were assessed by 24-hour pH-impedance monitoring before and after cow's milk protein (CMP) elimination. C-octanoate breath testing for gastric emptying dynamics, dual-sugar intestinal permeability, fecal calprotectin, and serum vitamin D were also measured. RESULTS: Fifty infants (mean age 13 ±â€Š7 weeks; 27 boys) were enrolled. On the basis of CMP elimination-challenge outcomes, 14 (28%) were categorized as non-IgE-mediated CMPA, and 17 (34%) were not allergic to milk; 12 infants with equivocal findings, and 7 with incomplete data were excluded. There were no baseline differences in GERD parameters between infants with and without CMPA. In the CMPA group, CMP elimination resulted in a significant reduction in reflux symptoms, esophageal acid exposure (reflux index), acid clearance time, and an increase in esophageal mucosal impedance. CONCLUSIONS: In infants with persistent crying, upper gastrointestinal motility parameters did not reliably differentiate between non-IgE-mediated CMPA and functional GERD. In the group with non-IgE-mediated CMPA, elimination of CMP significantly improved GERD symptoms, esophageal peristaltic function, and mucosal integrity.

Preliminary report of the (13)C-mixed triglyceride breath test to assess timing of pancreatic enzyme replacement therapy in children with cystic fibrosis.

BACKGROUND: Despite guidelines suggesting pancreatic enzyme replacement therapy (PERT) should be taken before or during a meal, it is currently unknown whether this has benefits over administration after a meal in individuals with cystic fibrosis (CF). METHODS: 18 children with pancreatic insufficient CF were randomised to two (13)C-mixed triglyceride ((13)C-MTG) breath tests to assess lipase activity with PERT administered 10min before and 10min after a meal. Results were expressed as percentage cumulative dose recovered (PCDR) of (13)CO2 and were compared with established values in healthy subjects. Gastric half emptying time (T½) was also assessed by a (13)C-octanoate breath test. RESULTS: There was no difference in mean PCDR of (13)CO2 between taking PERT before versus after the meal (p=0.68). Eleven subjects had a greater PCDR when PERT was taken before and 7 when PERT was taken after the meal. 6/8 subjects (75%) with a lower than normal PCDR at one time point normalised PCDR when PERT timing was changed. When PERT was taken after the meal, PCDR was higher in normal vs. fast T½ (p=0.04). CONCLUSIONS: Changing PERT timing can result in normalised lipase activity. Gastric emptying rate may influence optimal timing of PERT. Clinical Trial Registration Number - This study was undertaken prior to the registration process being a commonly required practice.

Pharmacokinetics and Acid-suppressive Effects of Esomeprazole in Infants 1-24 Months Old With Symptoms of Gastroesophageal Reflux Disease.

OBJECTIVES: To evaluate the pharmacokinetics and acid-suppressive effects of esomeprazole in infants with gastroesophageal reflux disease (GERD). PATIENTS AND METHODS: In this single-blind, randomized, parallel-group study, 50 infants 1 to 24 months old with symptoms of GERD, and ≥ 5% of time with intraesophageal pH <4 during 24-hour dual pH monitoring, received oral esomeprazole 0.25 mg/kg (n = 26) or 1 mg/kg (n = 24) once daily for 1 week. Intraesophageal and intragastric pH were recorded at 1 week, and blood samples were taken for pharmacokinetic analysis. RESULTS: At baseline, mean percentages of time with intragastric pH >4 and intraesophageal pH <4 were 30.5% and 11.6%, respectively, in the esomeprazole 0.25 mg/kg group and 28.6% and 12.5% in the esomeprazole 1 mg/kg group. After 1 week of treatment, times with intragastric pH >4 were 47.9% and 69.3% in the esomeprazole 0.25 mg/kg and 1 mg/kg groups, respectively (P < 0.001 vs baseline), and times with intraesophageal pH <4 were 8.4% (P < 0.05 vs baseline) and 5.5% (P < 0.001 vs. baseline), respectively. The mean number of acid reflux episodes of >5 minutes duration decreased from 6 at baseline to 3 and 2 with esomeprazole 0.25 mg/kg and 1 mg/kg, respectively. The geometric mean AUC0-t of esomeprazole were 0.24 and 1.79 µmol · h/L for the 0.25 mg/kg and 1 mg/kg dosages of esomeprazole, respectively. Both esomeprazole dosages were well tolerated. CONCLUSIONS: Oral treatment with esomeprazole 0.25 mg/kg and 1 mg/kg was well tolerated and provided dose-related acid suppression, dose-related exposure to esomeprazole, and decreased esophageal acid exposure in infants 1-24 months old with GERD.

Pharmacokinetics and Acid-suppressive Effects of Esomeprazole in Infants 1-24 Months Old With Symptoms of Gastroesophageal Reflux Disease.

OBJECTIVES: To evaluate the pharmacokinetics and acid-suppressive effects of esomeprazole in infants with gastroesophageal reflux disease (GERD). PATIENTS AND METHODS: In this single-blind, randomized, parallel-group study, 50 infants 1 to 24 months old with symptoms of GERD, and ≥ 5% of time with intraesophageal pH <4 during 24-hour dual pH monitoring, received oral esomeprazole 0.25 mg/kg (n = 26) or 1 mg/kg (n = 24) once daily for 1 week. Intraesophageal and intragastric pH were recorded at 1 week, and blood samples were taken for pharmacokinetic analysis. RESULTS: At baseline, mean percentages of time with intragastric pH > 4 and intraesophageal pH < 4 were 30.5% and 11.6%, respectively, in the esomeprazole 0.25 mg/kg group and 28.6% and 12.5% in the esomeprazole 1 mg/kg group. After 1 week of treatment, times with intragastric pH >4 were 47.9% and 69.3% in the esomeprazole 0.25 mg/kg and 1 mg/kg groups, respectively (P < 0.001 vs baseline), and times with intraesophageal pH < 4 were 8.4% (P < 0.05 vs baseline) and 5.5% (P < 0.001 vs. baseline), respectively. The mean number of acid reflux episodes of > 5 minutes duration decreased from 6 at baseline to 3 and 2 with esomeprazole 0.25 mg/kg and 1 mg/kg, respectively. The geometric mean AUC0-t of esomeprazole were 0.24 and 1.79 µmol · h/L for the 0.25 mg/kg and 1 mg/kg dosages of esomeprazole, respectively. Both esomeprazole dosages were well tolerated. CONCLUSIONS: Oral treatment with esomeprazole 0.25 mg/kg and 1 mg/kg was well tolerated and provided dose-related acid suppression, dose-related exposure to esomeprazole, and decreased esophageal acid exposure in infants 1-24 months old with GERD.

Zinc-fortified oral rehydration solution improved intestinal permeability and small intestinal mucosal recovery.

A randomized double-blind placebo-controlled study was conducted in children admitted to hospital with gastroenteritis (≥3 loose stools per day). All were treated for 5 days following admission with either zinc (Zn, 3 mg) or without Zn-fortified rice-based oral rehydration solution (ORS). (13)C-sucrose breath test (SBT) and intestinal permeability (lactulose/rhamnose or L/R ratio) were performed concurrently prior to commencement of ORS with or without Zn and at day 5 post-admission. There was a significant improvement in the SBT results in both the Zn-fortified group, median (5th-95th percentile) 2.1% (0.4% to 8.3%) versus 4.4% (0.4% to 10.4%), P < .05, and control group, 1.4% (0.1% to 5.4%) versus 4.3% (0.4% to 11.4%), P < .05, between the day of admission and day 5 post-admission. In the Zn-fortified group, there was also a significant improvement in L/R ratio between the day of admission and day 5 post-admission, 53.0 (19.5-90.6) versus 17.7 (13.4-83.2), P < .05. Low levels of Zn improved intestinal permeability but did not enhance short-term recovery following diarrheal illness.

Body positioning and medical therapy for infantile gastroesophageal reflux symptoms.

OBJECTIVE: Proton-pump inhibitors (PPIs) reduce acid gastroesophageal reflux (GER) and esophageal acid exposure in infants; however, they do not reduce total GER or symptoms attributed to GER. Reflux is reduced in the left lateral position (LLP). We hypothesize that the effect of LLP in combination with acid suppression is most effective in reducing GER symptoms in infants. METHODS: In this prospective sham-controlled trial, infants (0-6 months) with symptoms suggestive of gastroesophageal reflux disease were studied using 8-hour pH-impedance, cardiorespiratory and video monitoring, direct nurse observation, and a validated questionnaire. Infants demonstrating a positive GER symptom association were randomized to 1 of 4 groups; PPI + LLP, PPI + head of cot elevation (HE), antacid (AA) + LLP, or AA + HE. HE and AA were considered "sham" therapies. After 2 weeks the 8-hour studies were repeated on-therapy. RESULTS: Fifty-one patients were included (aged 13.6 [2-26] weeks). PPI + LLP was most effective in reducing GER episodes (69 [13] to 46 [10], P < 0.001) and esophageal acid exposure (median [interquartile range] 8.9% [3.1%-18.1%] to 1.1% [0%-4.4%], P = 0.02). No treatment group showed improvement in crying/irritability, although vomiting was reduced in AA + LLP (from 7 [2] to 2 [0] episodes P = 0.042). LLP compared with HE produced greater reduction in total GER (-21 [4] vs -10 [4], P = 0.056), regardless of acid-suppressive therapy. Acid exposure was reduced on PPI compared with AA (-6.8 [2.1] vs -0.9 [1.4]%, pH < 4, P = 0.043) regardless of positional intervention. A post-hoc analysis using automated analysis software revealed a significant reduction in crying symptoms in the PPI + LLP group (99 [65-103] to 62 [32-96] episodes, P = 0.018). CONCLUSIONS: "Symptomatic gastroesophageal reflux disease" implies disease causation for distressing infant symptoms. In infants with symptoms attributed to GER, LLP produced a significant reduction in total GER, but did not result in a significant improvement in symptoms other than vomiting; however, automated analysis appeared to identify infants with GER-associated crying symptoms who responded to positioning therapy. This is an important new insight for future research.

Objective assessment of swallow function in children with suspected aspiration using pharyngeal automated impedance manometry.

OBJECTIVES: The purpose of the present study was to apply a new method, pharyngeal automated impedance manometry (AIM), as an objective assessment tool of swallow function relevant to aspiration, in a cohort of paediatric patients with dysphagia. METHODS: We studied 20 children (mean age 6 years [5 months to 13.4 years]) referred for videofluoroscopy to assess aspiration risk with simultaneous manometry-impedance. Fluoroscopic evidence of aspiration was scored using a validated aspiration-penetration score. Pressure-flow profiles were analysed using AIM analysis measuring peak pressure, pressure at nadir impedance, time from nadir impedance to peak pressure, and flow interval. These variables were combined into a swallow risk index (SRI). RESULTS: Six of 20 children presented with deglutitive aspiration during videofluoroscopic assessment of swallowing. Of 58 liquid swallows analysed, in 9 aspiration was observed. Multiple logistic regression identified longer flow interval (P < 0.05), higher SRI (P < 0.05) and increased pressure in the upper oesophageal sphincter during maximal bolus flow (P < 0.05) to be the dominant risk variables predictive of aspiration in children. Each of these nonradiologically derived pressure-flow variables correlated with higher aspiration scores on videofluoroscopy (P < 0.01). CONCLUSIONS: We present novel, preliminary findings in children with deglutitive aspiration, suggesting that pharyngeal AIM can detect alterations in pressure-flow characteristics of swallowing that predispose to aspiration risk.

Efficacy and safety of once-daily esomeprazole for the treatment of gastroesophageal reflux disease in neonatal patients.

OBJECTIVE: To evaluate the efficacy and safety of proton pump inhibitors in infants aged <1 year with gastroesophageal reflux disease (GERD). STUDY DESIGN: In this randomized, double-blind, placebo-controlled multicenter study, neonates (premature to 1 month corrected age; n = 52) with signs and symptoms of GERD received esomeprazole 0.5 mg/kg or placebo once daily for up to 14 days. Change from baseline in the total number of GERD symptoms (from video monitoring) and GERD-related signs (from cardiorespiratory monitoring) was assessed with simultaneous esophageal pH, impedance, cardiorespiratory, and 8-hour video monitoring. RESULTS: There were no significant differences between the esomeprazole and placebo groups in the percentage change from baseline in the total number of GERD-related signs and symptoms (-14.7% vs -14.1%, respectively). Mean change from baseline in total number of reflux episodes was not significantly different between esomeprazole and placebo (-7.43 vs -0.2, respectively); however, the percentage of time pH was <4.0 and the number of acidic reflux episodes >5 minutes in duration was significantly decreased with esomeprazole vs placebo (-10.7 vs 2.2 and -5.5 vs 1.0, respectively; P ≤ .0017). The number of patients with adverse events was similar between treatment groups. CONCLUSIONS: Signs and symptoms of GERD traditionally attributed to acidic reflux in neonates were not significantly altered by esomeprazole treatment. Esomeprazole was well tolerated and reduced esophageal acid exposure and the number of acidic reflux events in neonates.

Phase I, multicenter, randomized, open-label study evaluating the pharmacokinetics and safety profile of repeated once-daily doses of intravenous esomeprazole in children 0 to 17 years of age.

BACKGROUND: Several oral proton pump inhibitors (PPIs) are currently approved for use in pediatric patients in North America and Europe. However, when use of oral therapy is not possible or appropriate, intravenous formulations of PPIs may be helpful. Intravenous esomeprazole is approved in the United States for the short-term treatment of gastroesophageal reflux disease (GERD) with erosive esophagitis in adults and in pediatric patients 1 month to 17 years of age (inclusive) as an alternative to oral therapy. Four open-label, randomized, 2-way crossover studies in adults with GERD found no clinically relevant differences in acid suppression between repeated doses of oral and intravenous esomeprazole. However, the pharmacokinetics of intravenous esomeprazole has not been studied extensively in children. OBJECTIVE: The aim of this study was to evaluate steady-state pharmacokinetics and tolerability of repeated doses of intravenous esomeprazole in children. METHODS: In this multicenter, open-label study, hospitalized patients (0-17 years of age) considered for acid suppression therapy received once-daily intravenous esomeprazole sodium for injection at 0.5 mg/kg (0-1 month of age), 1.0 mg/kg (1-11 months of age), 10 mg (1-5 years of age), 10 or 20 mg (6-11 years of age), or 20 or 40 mg (12-17 years of age) for 4 days. Children 6 to 11 years of age (inclusive) were randomized in a 1:1 ratio to receive esomeprazole 10 or 20 mg, and adolescents 12 to 17 years of age (inclusive) were randomized in a 1:1 ratio to receive esomeprazole 20 or 40 mg. Blood samples were drawn pre- and post-dose. Plasma esomeprazole was measured using reversed-phase liquid chromatography and mass spectrometry. Pharmacokinetic variables were derived using mixed-effects modeling. Adverse events (AEs) were assessed. RESULTS: Fifty-nine patients were randomized and 57 received the study drug. A majority of patients were white (44 white, 5 black/African American, 3 Asian, 5 other) and male (35/57). Fifty patients were eligible for pharmacokinetic analysis, including 6 to 8 patients in each age group. Esomeprazole pharmacokinetics was dose proportional and related to weight and age. Clearance increased with increasing weight and age. The mean AUC(τ) ranged from 6.9 µmol · h/L (10 mg, 6-11 years) to 17.6 µmol · h/L (40 mg, 12-17 years). The mean C(ss,max) ranged from 3.7 µmol/L (0.5 mg/kg, 0-1 month) to 10.5 µmol/L (40 mg, 12-17 years). Thirty-one patients experienced 1 or more AEs; 6 patients experienced 1 or more treatment-unrelated serious AEs. CONCLUSIONS: Intravenous esomeprazole at doses resulting in targeted AUC(τ) and C(ss,max) similar to therapeutic exposure in adults appeared to be reasonably well tolerated in this small, select pediatric population. ClinicalTrials.gov identifier: NCT00474019.

Whey- vs casein-based enteral formula and gastrointestinal function in children with cerebral palsy.

OBJECTIVES: Children with severe cerebral palsy (CP) commonly have gastrointestinal (GI) dysfunction. Whey-based enteral formulas have been postulated to reduce gastroesophageal reflux (GOR) and accelerate gastric emptying (GE). The authors investigated whether whey-based (vs casein-based) enteral formulas reduce GOR and accelerate GE in children who have severe CP with a gastrostomy and fundoplication. METHODS: Thirteen children received a casein-based formula for 1 week and either a 50% whey whole protein (50% WWP) or a 100% whey partially hydrolyzed protein (100% WPHP) formula for 1 week. Reflux episodes, gastric half-emptying time (GE t(1/2)), and reported pain and GI symptoms were measured. RESULTS: Whey formulas emptied significantly faster than casein (median [interquartile range (IQR)] GE t(1/2), 33.9 [25.3-166.2] min vs 56.6 [46-191] min; P = .033). Reflux parameters were unchanged. GI symptoms were lower in children who received 50% WWP (visual analog symptom score, median [IQR], 0 [0-11.8]) vs 100% WPHP (13.0 [2.5-24.8]) (P = .035). CONCLUSION: This pilot study shows that in children who have severe CP with a gastrostomy and fundoplication, GE of the whey-based enteral formula is significantly faster than casein. The acceleration in GE does not alter GOR frequency, and there appears to be no effect of whey vs casein in reducing acid, nonacid, and total reflux episodes. The results indicate that enteral formula selection may be particularly important for children with severe CP and delayed GE.

Distension of the esophagogastric junction augments triggering of transient lower esophageal sphincter relaxation.

Patients with gastroesophageal reflux disease show an increase in esophagogastric junction (EGJ) distensibility and in frequency of transient lower esophageal sphincter relaxations (TLESR) induced by gastric distension. The objective was to study the effect of localized EGJ distension on triggering of TLESR in healthy volunteers. An esophageal manometric catheter incorporating an 8-cm internal balloon adjacent to a sleeve sensor was developed to enable continuous recording of EGJ pressure during distension of the EGJ. Inflation of the balloon doubled the cross-section of the trans-sphincteric portion of the catheter from 5 mm OD (round) to 5 × 11 mm (oval). Ten healthy subjects were included. After catheter placement and a 30-min adaptation period, the EGJ was randomly distended or not, followed by a 45-min baseline recording. Subjects consumed a refluxogenic meal, and recordings were made for 3 h postprandially. A repeat study was performed on another day with EGJ distension status reversed. Additionally, in one subject MRI was performed to establish the exact position of the balloon in the inflated state. The number of TLESR increased during periods of EGJ distension with the effect being greater after a meal [baseline: 2.0(0.0-4.0) vs. 4.0(1.0-11.0), P=0.04; postprandial: 15.5(10.0-33.0) vs. 22.0(17.0-58.0), P=0.007 for undistended and distended, respectively]. EGJ distension augments meal-induced triggering of TLESR in healthy volunteers. Our data suggest the existence of a population of vagal afferents located at sites in/around the EGJ that may influence triggering of TLESR.

Non-invasive detection of a palifermin-mediated adaptive response following chemotherapy-induced damage to the distal small intestine of rats.

INTRODUCTION: Pre-clinical studies have indicated that palifermin may be an effective treatment modality for intestinal mucositis, a debilitating complication of cancer chemotherapy. We determined whether palifermin was protective in rats with experimentally induced intestinal mucositis and the applicability of the sucrose breath test (SBT) to monitor palifermin for its efficacy as an anti-mucositis agent. RESULTS: SBT values and sucrase activity were reduced in all 5-FU-treated groups compared with untreated controls (p < 0.05). At 72 h post 5-FU, sucrase activity was higher in rats treated with palifermin compared with 5-FU controls (p < 0.05). Jejunal and ileal villus heights were lower in all 5-FU groups compared with saline controls. METHODS: Dark agouti rats (n = 10) were subcutaneously injected with palifermin or vehicle for 3 d after which they were injected with 5-fluorouracil (5-FU) and sacrificed after 72 h. The in vivo SBT and in vitro sucrase assay were used to evaluate small intestinal function and damage. Intestinal disease severity was determined by histological assessment of villus height and crypt depth. CONCLUSION: The SBT can monitor the ability of palifermin to modify the functional capacity of the small intestine in rats with intestinal mucositis. Further studies are indicated to investigate the prophylactic potential of palifermin against intestinal mucositis.

A novel method for the nonradiological assessment of ineffective swallowing.

OBJECTIVES: This validation study evaluates a new manometry impedance-based approach for the objective assessment of pharyngeal function relevant to postswallow bolus residue. METHODS: We studied 23 adult and pediatric dysphagic patients who were all referred for a videofluoroscopy, and compared these patients with 10 adult controls. The pharyngeal phase of swallowing of semisolid boluses was recorded with manometry and impedance. Fluoroscopic evidence of postswallow bolus residue was scored. Pharyngeal pressure impedance profiles were analyzed. Computational algorithms measured peak pressure (Peak P), pressure at nadir impedance (PNadImp), time from nadir impedance to PeakP (PNadImp-PeakP), the duration of impedance drop in the distal pharynx (flow interval), upper esophaghageal sphincter (UES) relaxation interval (UES-RI), nadir UES pressure (NadUESP), UES intrabolus pressure (UES-IBP), and UES resistance. A swallow risk index (SRI) was derived by the formula: SRI=(FI × PNadImp)/(PeakP × (TNadImp-PeakP+1)) × 100. RESULTS: In all, 76 patient swallows (35 with residue) and 39 control swallows (12 with residue) were analyzed. Different functional variables were found to be altered in relation to residue. In both controls and patients, flow interval was longer in relation to residue. In controls, but not patients, residue was associated with an increased PNadImp (suggestive of increased pharyngeal IBP). Controls with residue had increased UES-IBP, NadUESP, and UES resistance compared with patients with residue. Residue in patients was related to a prolonged UES-RI. The SRI was elevated in relation to residue in both controls and patients and an average SRI of 9 was optimally predictive of residue (sensitivity 75% and specificity 80%). CONCLUSIONS: We present novel findings in control subjects and dysphagic patients showing that combined manometry and impedance recordings can be objectively analyzed to derive pressure-flow variables that are altered in relation to the bolus residual and can be combined to predict ineffective pharyngeal swallowing.

4-aminobutyrate aminotransferase (ABAT): genetic and pharmacological evidence for an involvement in gastro esophageal reflux disease.

Gastro-esophageal reflux disease (GERD) is partly caused by genetic factors. The underlying susceptibility genes are currently unknown, with the exception of COL3A1. We used three independent GERD patient cohorts to identify GERD susceptibility genes. Thirty-six families, demonstrating dominant transmission of GERD were subjected to whole genome microsatellite genotyping and linkage analysis. Five linked regions were identified. Two families shared a linked region (LOD 3.9 and 2.0) on chromosome 16. We used two additional independent GERD patient cohorts, one consisting of 219 trios (affected child with parents) and the other an adult GERD case control cohort consisting of 256 cases and 485 controls, to validate individual genes in the linked region through association analysis. Sixty six single nucleotide polymorphism (SNP) markers distributed over the nine genes present in the linked region were genotyped in the independent GERD trio cohort. Transmission disequilibrium test analysis followed by multiple testing adjustments revealed a significant genetic association for one SNP located in an intron of the gene 4-aminobutyrate aminotransferase (ABAT) (P(adj) = 0.027). This association did not replicate in the adult case-control cohort, possibly due to the differences in ethnicity between the cohorts. Finally, using the selective ABAT inhibitor vigabatrin (γ-vinyl GABA) in a dog study, we were able to show a reduction of transient lower esophageal sphincter relaxations (TLESRs) by 57.3 ± 11.4 % (p = 0.007) and the reflux events from 3.1 ± 0.4 to 0.8 ± 0.4 (p = 0.007). Our results demonstrate the direct involvement of ABAT in pathways affecting lower esophageal sphincter (LES) control and identifies ABAT as a genetic risk factor for GERD.

Direct and indirect impact on rotavirus positive and all-cause gastroenteritis hospitalisations in South Australian children following the introduction of rotavirus vaccination.

Rotavirus vaccine for infants was introduced into the National Immunisation Program in Australia in July 2007. To determine the impact of rotavirus vaccination on gastroenteritis hospitalisations amongst children less than six years of age in South Australia, we conducted a retrospective analysis of hospital admissions over two time periods: 1 May 2005-30 April 2007 (prior to rotavirus vaccination introduction) and 1 May 2008-30 April 2010 (post rotavirus vaccination introduction). The introduction of rotavirus vaccination has been associated with a marked reduction in hospital admissions for serious rotavirus gastroenteritis (RVGE) and all-cause gastroenteritis (ACGE). Following the introduction of rotavirus vaccination in South Australia, there was an 83% reduction in RVGE coded admissions (955 vs 165) and a 48% reduction in ACGE coded admissions (4153 vs 2142) for children aged less than six years. Children less than two years demonstrated the greatest reduction (90%) in RVGE admissions and ACGE admissions (57%). Age-specific RVGE hospitalisation rates decreased from 933/100,000 prior to rotavirus vaccine introduction to 88/100,000 for children less than two years of age. In addition, for gastroenteritis hospitalisations for children aged five years at time of admission (unvaccinated cohort) there was a reduction in the number of RVGE cases (24 vs 4), a reduction in age-specific RVGE hospitalisation rates (65/100,000 vs 11/100,000) and a significant reduction in the proportion of overall gastroenteritis cases which were rotavirus positive (11.5% vs 3.5%), suggesting a positive impact on both unvaccinated and vaccinated children less than six years of age in South Australia.

Is small-bowel bacterial overgrowth an underdiagnosed disorder in children with gastrointestinal symptoms?

Small-bowel bacterial overgrowth (SBBO) has been implicated in chronic abdominal pain and irritable bowel syndrome in children. This was a retrospective study that aimed to assess the occurrence of SBBO by the lactulose breath hydrogen test in children referred primarily for investigation of carbohydrate malabsorption (n = 287). There were profiles indicative of SBBO in 16% (39/250) of hydrogen-producing children. This indicated that SBBO may be more common in children with gastrointestinal symptoms and apparent carbohydrate malabsorption than previously recognised.

A method to objectively assess swallow function in adults with suspected aspiration.

BACKGROUND & AIMS: Pharyngeal manometry and impedance provide information on swallow function. We developed a new analysis approach for assessment of aspiration risk. METHODS: We studied 20 patients (30-95 years old) with suspected aspiration who were referred for videofluoroscopy, along with controls (ages 24-47 years). The pharyngeal phase of liquid bolus swallowing was recorded with manometry and impedance. Data from the first swallow of a bolus and subsequent clearing swallows were analyzed. We scored fluoroscopic evidence of aspiration and investigated a range of computationally derived functional variables. Of these, 4 stood out as having high diagnostic value: peak pressure (PeakP), pressure at nadir impedance (PNadImp), time from nadir impedance to peak pressure (TNadImp-PeakP), and the interval of impedance drop in the distal pharynx (flow interval). RESULTS: During 54 liquid, first swallows and 40 clearing swallows, aspiration was observed in 35 (13 patients). Compared to those of controls, patient swallows were characterized by a lower PeakP, higher PNadImp, longer flow interval, and shorter TNadImp-PeakP. A Swallow Risk Index (SRI), designed to identify dysfunctions associated with aspiration, was developed from iterative evaluations of variables. The average first swallow SRI correlated with the average aspiration score (r = 0.846, P < .00001 for Spearman Rank Correlation). An average SRI of 15, when used as a cutoff, predicted aspiration during fluoroscopy for this cohort (κ = 1.0). CONCLUSIONS: Pressure-flow variables derived from automated analysis of combined manometric/impedance measurements provide valuable diagnostic information. When combined into an SRI, these measurements are a robust predictor of aspiration.

Optimisation of the reflux-symptom association statistics for use in infants being investigated by 24-hour pH impedance.

BACKGROUND AND AIM: pH-impedance monitoring is used to diagnose symptomatic gastroesophageal reflux (GER) based on symptom association probability (SAP). Current criteria for calculation of SAP are optimised for heartburn in adults. Infants, however, demonstrate a different symptom profile. The aim of the present study was to optimise criteria for calculation of SAP in infants with GER disease. PATIENTS AND METHODS: Ten infants referred for investigation of symptomatic reflux were enrolled. GER episodes were recorded using a pH-impedance probe, which remained in place for 48 hours. During the test, cough, crying, and regurgitation were marked. Impedance recordings were analysed for the occurrence of bolus reflux episodes. SAP for behaviors following reflux episodes was separately calculated for day 1 and day 2 using automated reporting software, which enabled the time window used for SAP calculations to be modified from 15 to 600 seconds. Day-to-day agreement of SAP was assessed by calculating the 95% limits of agreement (mean difference ± 1.96 standard deviations of differences) and their confidence intervals. RESULTS: The number of bolus GER episodes and symptom episodes reported did not differ from day to day. The best agreement in SAP between the 2 days was found using time intervals of 2 minutes for cough, 5 minutes for crying, and 15 seconds and/or 2 to 5 minutes for regurgitation. CONCLUSIONS: We conclude that the standard 2-minute time interval is appropriate for the investigation of cough and regurgitation symptoms. The day-to-day agreement of SAP for crying was poor using standard criteria, and our results suggest increasing the reflux-symptom association time interval to 5 minutes.

Intra-thoracic pancreatic pseudocyst: a rare complication of traumatic pancreatitis.

The commonest complication of traumatic pancreatitis is the development of pancreatic pseudocyst. We report a patient with traumatic pancreatitis following blunt abdominal trauma who developed an intrathoracic pancreatic pseudocyst late in the course of non-operative management, and discuss the management of this very rare complication of traumatic pancreatitis.