Adding a liquid test meal to a standardized lactulose hydrogen breath test significantly influences abdominal symptom generation and hydrogen values

OBJECTIVE

While single sugar tests are controversially discussed, combination tests with meals are gaining more attention. The aim of this study was to analyze the impact of adding a test meal to lactulose hydrogen breath tests (LHBT) on hydrogen values and abdominal symptoms in patients with functional gastrointestinal disorders (FGIDs).

METHODS

Data of 81 FGID patients between 2014-2018 were analyzed. Patients underwent LHBT with 30 g lactulose + 300 mL water and a nutrient challenge test (NCT) including 400 mL liquid test meal + 30 g lactulose. To statistically assess the effect of a test meal on abdominal symptoms and H2, mixed-effect models were used.

RESULTS

Adding a test meal to LHBT showed a significant increase in nausea [odds ratio (OR) 1.4; 95% confidence interval (CI), 1.1-1.7], decrease in abdominal pain (OR 0.7; 95% CI, 0.6-0.9), borborygmi (OR 0.5; 95% CI, 0.4-0.6), diarrhea (OR 0.4; 95% CI, 0.3-0.6), and H2 production (estimate -5.3, SE 0.7, P < 0.001). The effect on bloating was only significant in functional dyspepsia, irritable bowel syndrome-functional dyspepsia mixed type and functional abdominal pain/bloating (OR 0.1; 95% CI, 0.0-0.2; OR 1.7; 95% CI, 1.2-2.3 resp OR 4.4; 95% CI, 1.8-10.6).

CONCLUSIONS

Significant effects on abdominal symptoms and H2 production by adding a test meal to LHBT in FGID patients are shown. Increased occurrence of nausea may be caused by gastric/duodenal hypersensitivity; decreased H2, diarrhea and borborygmi by slower and more physiologic gastric emptying resulting in later arrival of the test substance in the bowel. We recommend NCTs instead of LHBT to more physiologically represent FGID patients' meal-induced burden.

Pyloric dilation with the esophageal functional lumen imaging probe in gastroparesis improves gastric emptying, pyloric distensibility, and symptoms

BACKGROUND AND AIMS

The role of decreased pyloric distensibility in gastroparesis as measured by the endolumenal functional luminal imaging probe (EndoFLIP) has been receiving increasing attention. In this study, we present clinical outcomes to pyloric dilation with the esophageal FLIP (EsoFLIP) in regard to gastric emptying, symptom evolution, and FLIP metrics.

METHODS

Patients evaluated for gastroparesis (gastric emptying studies of t_1/2 ≥180 minutes during ¹³C-octanoic acid breath test and/or gastric remnants during gastroscopy after a sufficient fasting period) were scheduled for EsoFLIP controlled pyloric dilation. Pre- and postprocedural gastric emptying studies, questionnaires (Patient Assessment of Upper GI Symptoms Severity Index [PAGI-SYM; including the Gastroparesis Cardinal Symptom Index] and Patient Assessment of Quality of Life Index [PAGI-QOL]), and FLIP metrics were documented. Dilation was conducted according to a self-developed algorithm.

RESULTS

Forty-six patients were analyzed (72% women; median age, 39 years [range, 18-88]). Etiologies of gastroparesis were diabetic in 10 patients (22%), idiopathic in 33 (72%), and postoperative in 3 (6%). Postprocedural gastric emptying time decreased from a median of 211 minutes to 179 minutes (P = .001). In accordance, pyloric distensibility, PAGI-SYM, PAGI-QOL, and Gastroparesis Cardinal Symptom Index values improved significantly. After a median follow-up of 3.9 months, 57% of all treated patients with returned questionnaires reported improved symptoms.

CONCLUSIONS

Pyloric EsoFLIP controlled dilation shows value in the treatment of gastroparesis, both subjectively and objectively. Long-term follow-up to assess efficacy and comparative trials are warranted.

Solid Swallow Examination During High Resolution Manometry and EGJ-Distensibility Help Identify Esophageal Outflow Obstruction in Non-obstructive Dysphagia

Single water swallow (SWS) high-resolution manometry (HRM) may miss relevant esophageal motility disorders. Solid test meal (STM) during HRM and lately the functional lumen imaging probe (FLIP) have been shown to be of diagnostic value in the assessment of motility disorders. We aimed to assess the diagnostic yield of STM and FLIP in non-obstructive dysphagia (NOD). Patients assessed for dysphagia with both HRM and FLIP between April 2016 and August 2019 were analyzed for signs of non-obstructive EGJ outflow obstruction (EGJOO) according to Chicago Classification 3.0 (CCv3) and CC adapted for the use with solid swallows (CC-S), followed by an individual group-specific analysis. Five subjects without dysphagia served as control group. Standard HRM- and FLIP-values as well as esophagograms and Eckardt Scores were analyzed. Forty-two patients were identified (male/female, 14/36, median age 62). Twenty-five (59.5%) were diagnosed with EGJOO during STM only (= SWS-negative patients; CC-S). The EGJ distensibility index (EGJ-DI) of symptomatic patients was significantly lower compared to the control group (p = 0.006). EGJ-DI was < 3mm²/mmHg in 67% and 88% of patients diagnosed according to CC-S and CCv3, respectively. The IRP during STM showed a significant association to the corresponding EGJ-DI values (p < 0.001). Seventy-six percent of patients received treatment because of additional STM evaluation with a favorable clinical response rate of 89%. STM and FLIP identify EGJOO in symptomatic patients with normal SWS during HRM. STM resembles an inexpensive and clinically meaningful option to diagnose motility disorders and helps to select patients for interventional treatment.

Nutrient Challenge Testing Is Not Equivalent to Scintigraphy-Lactulose Hydrogen Breath Testing in Diagnosing Small Intestinal Bacterial Overgrowth

Background/Aims

Small intestinal bacterial overgrowth (SIBO) is a common condition in disorders of gut-brain interaction (DGBI). Recently, a combined scintigraphy–lactulose hydrogen breath test (ScLHBT) was described as an accurate tool diagnosing SIBO. We aim to analyze whether a lactulose nutrient challenge test (NCT), previously shown to separate DGBI from healthy volunteers, is equivalent to ScLHBT in diagnosing SIBO.

Methods

We studied data of 81 DGBI patients undergoing ScLHBT with 30 g lactulose and 300 mL water as well as NCT with 30 g lactulose and a 400 mL liquid test meal. Differences in proportion of positive SIBO diagnoses according to specified cecal load and time criteria for NCT and ScLHBT, respectively, were tested in an equivalence trial. An odds ratio (OR) range of 0.80-1.25 was considered equivalent.

Results

Diagnosis of SIBO during NCT was not equivalent to SIBO diagnosis in ScLHBT, considering a hydrogen increase before cecal load of 5.0%, 7.5%, or 10.0%, respectively ([OR, 3.76; 90% CI, 1.99-7.09], [OR, 1.87; 90% CI, 1.06-3.27], and [OR, 1.11; 90% CI, 0.65-1.89]). Considering only time to hydrogen increase as criterion, the odds of a positive SIBO diagnosis in the NCT (0.65) was lower than in ScLHBT (1.70) (OR, 0.38; 90% CI, 0.23-0.65).

Conclusions

This study could not show an equivalence of NCT and ScLHBT in diagnosing SIBO. A possible explanation might be the different transit times owing to unequal testing substances. The effect of this deviation in relation to consecutive therapy regimens should be tested in further prospective studies.

Short-term outcome after singular hydraulic EsoFLIP dilation in patients with achalasia: A feasibility study

BACKGROUND

Achalasia is a chronic esophageal motility disorder characterized by impaired relaxation of the lower esophageal sphincter, determined by an elevated integrated relaxation pressure (IRP > 15 mm Hg) and absent peristalsis. Goal of treatment is facilitation of flow across the EGJ but minimizing postinterventional reflux. A new advanced hydraulic dilation technology, the esophageal functional luminal imaging probe (EsoFLIP), allows dynamic monitoring of hollow organ dimensions while performing hydraulic dilation. The aim of our study was to evaluate the treatment response after single EsoFLIP dilation in achalasia patients.

METHODS

Dilation was performed under endoscopic control with the EsoFLIP device using a self-developed dilation algorithm. Symptom scores were assessed by the Eckardt score (ES) before and 1-4 weeks after intervention. Esophageal emptying before and after intervention was recorded with timed barium esophagogram.

KEY RESULTS

We studied 28 consecutive untreated achalasia patients (8 female) with a median age of 43 years (range 19-82 years) undergoing their first dilation performed with the EsoFLIP, aiming at a maximum dilation diameter of 25 mm. Total ES was significantly reduced from 7 at baseline to 2 postintervention (P < .001). The median height of the barium column after 5 minutes was significantly reduced from 4.5 cm at baseline to 1.7 cm (P = .0087). No major complications occurred.

CONCLUSIONS & INFERENCES

We found good efficacy in both subjective and objective short-term treatment outcome after singular EsoFLIP dilation in treatment-naive achalasia patients. Our findings suggest that EsoFLIP is a promising dilation technology that should be further studied in a larger, controlled setting with longer follow-up.

Endoscope presence during endoluminal functional lumen imaging probe (FLIP) influences FLIP metrics in the evaluation of esophageal dysmotility

BACKGROUND

The functional lumen imaging probe (FLIP) system is an FDA-approved tool for dynamic evaluation of the esophagogastric junction (EGJ). Even though commercially available since 2009, FLIP utilization remains low, partly due to lack of consensus in methodology and interpretation. Therefore, we aimed to analyze the influence of concurrent endoscopy on FLIP measurements.

METHODS

In this single-center study, we reviewed data from 93 patients undergoing FLIP for symptomatic esophageal motility disorders between 2016 and 2018. During sedated endoscopy, we measured luminal values (distensibility, cross-sectional area (CSA), and balloon pressure) at the EGJ and distal esophagus using 30, 40, and 50 mL distension volumes, with and without concurrent endoscope presence. All recorded values were compared at the various distension volumes between the two measurements using a Wilcoxon rank sum test.

KEY RESULTS

There was a significant difference in distensibility and CSA with index distension volume (40 mL) at the EGJ comparing the two measurements: Lower median distensibility was 2.1 mm²  mm Hg^-1 in the group with concurrent inserted endoscope, respectively, 3.4 mm²  mm Hg^-1 without endoscope (P < .001), and median CSA was 86.0 resp. 110.0 mm² (P < .001). No significant difference could be found in the measurements of the distal esophagus.

CONCLUSIONS & INFERENCES

Our results show a significant difference in FLIP measurements with and without endoscope presence. This underlines the importance of establishing a consensus of a standardized FLIP protocol to define normal luminal values and guiding future FLIP diagnostic studies.

Differentiation of functional gastrointestinal disorders from healthy volunteers by lactulose hydrogen breath test and test meal

BACKGROUND AND AIM

Functional dyspepsia (FD) is a common disorder of gut-brain interaction with incompletely understood pathophysiology. Consequently, heterogeneous expert opinions on diagnostic tests and assessment of treatment efficacies exist. So far, no consensus about the most relevant diagnostic and outcome tool has been reached. In this study, we aimed to analyze the significance of a combined lactulose hydrogen breath test (LHBT) and liquid meal, yet representing a standardized test in irritable bowel syndrome (IBS), in FD.

METHODS

We analyzed data of 146 FD, 204 IBS patients, and 50 healthy volunteers (HV). All patients underwent LHBT with a meal-drink consisting of 30-g Lactulose and 400-mL Ensure®. Effect of abdominal symptom generation in FD/IBS compared with HV was assessed on a patient-reported Likert-scale.

RESULTS

There was a significant difference between FD/IBS patients and HV in LHBT-induced abdominal pain (odds ratio [OR] 246.9, 95% confidence interval [CI] 26.6-2290.7; OR 161.2, 95% CI 16.9-1534.8), abdominal bloating (OR 384.8, 95% CI 92.9-2135.4; OR 524.1, 95% CI 114.7-3432.3), borborygmi (OR 9.9, 95% CI 2.2-46.9; OR 17.7, 95% CI 4.7-67.4), nausea only in FD (OR 174.4, 95% CI 15.5-5375.5), and diarrhea in IBS only (OR 25.8, 95% CI 2.0-7012.6). Hydrogen production was not significantly different in FD/IBS and HV.

CONCLUSIONS

In this study, we demonstrated significant differences in postprandial symptom generation in FD and IBS compared with HV after LHBT. This does not only allow us to discriminate FD/IBS from HV but may also represent a diagnostic and monitoring tool for FD/IBS in the future, including monitoring of treatment effects.