Hydrogen breath tests in gastrointestinal diseases

Approach to a Child with Chronic Diarrhea

Chronic diarrhea in children is challenging both with regards to etiological diagnosis and for management. Etiology and pathophysiological mechanisms vary widely from neonates to adolescents. Congenital or genetic causes are more frequent in neonates, while infections, allergy and immune-mediated mechanisms are more frequent in childhood. A thorough history and proper physical examination are required to decide for further diagnostic evaluation. The approach to a child with chronic diarrhea should be age specific and based predominantly on the pathophysiological mechanism involved. The nature of the stool like watery, bloody or fatty (steatorrhea) can suggest the probable etiology and organ system involved. After routine tests, evaluation with specific serological tests, imaging, endoscopy (gastroscopy/colonoscopy), histopathology of intestinal mucosa, breath tests or radionuclide imaging may be required to make a definitive diagnosis. Genetic evaluation is important in congenital diarrheas, monogenic inflammatory bowel disease (IBD) and immunodeficiency disorders. Management is aimed at stabilization, nutritional support and etiology specific treatment. Specific therapy can be as simple as exclusion of specific nutrient or as complicated as small bowel transplant. Evaluation and management require expertise and thus patients need to be referred in a timely fashion. This will minimise morbidity including nutritional consequences and improve outcome.

Fructose malabsorption and fructan malabsorption are associated in patients with irritable bowel syndrome

BACKGROUND

Food malabsorption and intolerance is implicated in gastrointestinal symptoms among patients with irritable bowel syndrome (IBS). Key triggers include fructose and fructan. Prior studies examined fructose and fructan malabsorption separately in IBS patients. None have concurrently assessed both within the same patient group. We aimed to investigate the association between fructose and fructan malabsorption in the same patients with IBS using hydrogen breath testing (HBT).

METHODS

We retrospectively identified patients with IBS who underwent fructose and fructan HBTs and abstracted their results from the electronic medical record. Fructose and fructan HBTs were performed by administering a 25 g fructose solution or 10 g fructan solution, followed by breath hydrogen readings every 30 min for 3 h. Patients were positive for fructose or fructan malabsorption if breath hydrogen levels exceeded 20 ppm.

RESULTS

Of 186 IBS patients, 71 (38.2%) were positive for fructose malabsorption and 91 (48.9%) were positive for fructan malabsorption. Of these patients, 42 (22.6%) were positive for fructose malabsorption and fructan malabsorption. Positive fructose HBT readings were significantly associated with positive fructan HBT readings (p = 0.0283). Patients positive for fructose malabsorption or fructan malabsorption had 1.951 times higher odds of testing positive for the other carbohydrate.

CONCLUSIONS

Our results reveal a clinically significant association between fructose malabsorption and fructan malabsorption in patients with IBS. Fructan malabsorption should be assessed in patients with fructose malabsorption, and vice versa. Further studies are required to identify the mechanisms underlying our findings.

Approach to the diagnosis and management of dysbiosis

All microorganisms like bacteria, viruses and fungi that reside within a host environment are considered a microbiome. The number of bacteria almost equal that of human cells, however, the genome of these bacteria may be almost 100 times larger than the human genome. Every aspect of the physiology and health can be influenced by the microbiome living in various parts of our body. Any imbalance in the microbiome composition or function is seen as dysbiosis. Different types of dysbiosis are seen and the corresponding symptoms depend on the site of microbial imbalance. The contribution of the intestinal and extra-intestinal microbiota to influence systemic activities is through interplay between different axes. Whole body dysbiosis is a complex process involving gut microbiome and non-gut related microbiome. It is still at the stage of infancy and has not yet been fully understood. Dysbiosis can be influenced by genetic factors, lifestyle habits, diet including ultra-processed foods and food additives, as well as medications. Dysbiosis has been associated with many systemic diseases and cannot be diagnosed through standard blood tests or investigations. Microbiota derived metabolites can be analyzed and can be useful in the management of dysbiosis. Whole body dysbiosis can be addressed by altering lifestyle factors, proper diet and microbial modulation. The effect of these interventions in humans depends on the beneficial microbiome alteration mostly based on animal studies with evolving evidence from human studies. There is tremendous potential for the human microbiome in the diagnosis, treatment, and prognosis of diseases, as well as, for the monitoring of health and disease in humans. Whole body system-based approach to the diagnosis of dysbiosis is better than a pure taxonomic approach. Whole body dysbiosis could be a new therapeutic target in the management of various health conditions.

Mesenchymal Stem Cell Priming: Potential Benefits of Administration of Molecular Hydrogen

Stem cell therapy has emerged as a promising avenue for regenerative medicine, offering the potential to treat a wide range of debilitating diseases and injuries. Among the various types of stem cells, mesenchymal stem cells (MSCs) have garnered significant attention due to their unique properties and therapeutic potential. In recent years, researchers have been exploring novel approaches to enhance the effectiveness of MSC-based therapies. One such approach that has gained traction is the priming of MSCs with molecular hydrogen (H2). This article delves into the fascinating world of mesenchymal stem cell priming with molecular hydrogen and the potential benefits it holds for regenerative medicine.

Prebiotic Strategies to Manage Lactose Intolerance Symptoms

Lactose intolerance, which affects about 65-75% of the world's population, is caused by a genetic post-weaning deficiency of lactase, the enzyme required to digest the milk sugar lactose, called lactase non-persistence. Symptoms of lactose intolerance include abdominal pain, bloating and diarrhea. Genetic variations, namely lactase persistence, allow some individuals to metabolize lactose effectively post-weaning, a trait thought to be an evolutionary adaptation to dairy consumption. Although lactase non-persistence cannot be altered by diet, prebiotic strategies, including the consumption of galactooligosaccharides (GOSs) and possibly low levels of lactose itself, may shift the microbiome and mitigate symptoms of lactose consumption. This review discusses the etiology of lactose intolerance and the efficacy of prebiotic approaches like GOSs and low-dose lactose in symptom management.

MXene-Based Elastomer Mimetic Stretchable Sensors: Design, Properties, and Applications

Flexible sensors based on MXene-polymer composites are highly prospective for next-generation wearable electronics used in human-machine interfaces. One of the motivating factors behind the progress of flexible sensors is the steady arrival of new conductive materials. MXenes, a new family of 2D nanomaterials, have been drawing attention since the last decade due to their high electronic conductivity, processability, mechanical robustness and chemical tunability. In this review, we encompass the fabrication of MXene-based polymeric nanocomposites, their structure-property relationship, and applications in the flexible sensor domain. Moreover, our discussion is not only limited to sensor design, their mechanism, and various modes of sensing platform, but also their future perspective and market throughout the world. With our article, we intend to fortify the bond between flexible matrices and MXenes thus promoting the swift advancement of flexible MXene-sensors for wearable technologies.

The Prevalence of Small Intestinal Bacterial Overgrowth After Roux-en-Y Gastric Bypass (RYGB): a Systematic Review and Meta-analysis

We reviewed the literature on the prevalence of small intestinal bacterial overgrowth (SIBO) after Roux-en-Y gastric bypass (RYGB). Eight studies examining 893 patients were included. The mean age of the patients was 48.11 ± 4.89 years. The mean BMI before surgery and at the time of SIBO diagnosis was 44.57 ± 2.89 kg/m2 and 31.53 ± 2.29 kg/m2, respectively. Moreover, the results showed a 29% and 53% prevalence of SIBO at < 3-year and > 3-year follow-up after RYGB, respectively. Symptoms included abdominal pain, diarrhea, bloating, nausea, vomiting, constipation, soft stool, frequent defecation, flatulence, rumpling, dumping syndrome, and irritable bowel syndrome. SIBO is prevalent after RYGB; digestive symptoms should prompt the consideration of SIBO as a potential etiology. Antibiotic therapy has proven to be therapeutic.

High Prevalence of Small Intestinal Bacterial Overgrowth Syndrome in ICU Patients: An Observational Study

Background: Small intestinal bacterial overgrowth (SIBO), although associated with potentially serious complications, has not been adequately studied in critically ill patients. The primary objective of this study was to assess the prevalence of SIBO in critically ill patients. Secondary outcomes included the assessment of its effect on ventilator-associated pneumonia (VAP), intensive care unit (ICU) length of stay (LOS), and all-cause in-hospital mortality rate. Methods: This prospective observational study was conducted in a mixed medical-surgical ICU. In 52 consecutive ICU patients, a noninvasive modified hydrogen breath test (HBT) with lactulose was employed for SIBO diagnosis. The HBT was conducted at predetermined time intervals (first day of admission; third, fifth, and seventh day of ICU stay). Patients with an abnormal HBT suggesting SIBO on the day of ICU admission were excluded from the study. Participants were classified as either positive or negative based on their HBT on the third, fifth, and/or seventh day. A comparative assessment of demographic data, APACHE II score, incidence of VAP, duration of ICU stay, and all-cause in-hospital mortality was conducted. Multivariate logistic regression analysis was performed to identify the predictive factors for SIBO. Results: The groups were homogeneous in terms of their baseline characteristics. The prevalence of SIBO was 36.5%. The all-cause in-hospital mortality was 34.6%. The presence of SIBO was associated with an increased incidence of VAP (P < .001) and a prolonged ICU length of stay (P < .033). All-cause in-hospital mortality was similar between the groups. Regarding the results of the multivariate logistic regression model, only age was identified as a statistically significant independent predictor of SIBO (OR 1.08, P = .018). Conclusions: The prevalence of SIBO in ICU patients appears to be increased. Both early diagnosis and effective treatment are of utmost importance, especially for critically ill patients since it appears to be associated with VAP and prolonged hospitalization.

A Narrative Review of Human Clinical Trials to Improve Lactose Digestion and Tolerance by Feeding Bifidobacteria or Galacto-Oligosacharides

Supplementation with the probiotic Bifidobacterium and prebiotic galacto-oligosaccharides (GOS) could improve gut health and benefit lactose intolerant individuals. A narrative review was conducted to identify human clinical trials that evaluated lactose digestion and/or tolerance in response to consumption of Bifidobacterium, GOS, or both. A total of 152 studies on Bifidobacterium and GOS or both were published between 1983 and 2022. Out of the 152 studies, 20 were human clinical trials conducted in lactose intolerant subjects; 8 studies were conducted with Bifidobacterium supplementation and 3 studies involved GOS supplementation. Five studies reported favorable outcomes of Bifidobacterium supplementation in managing lactose intolerance (LI). Similarly, three studies reported favorable outcomes with GOS supplementation. The other three studies reported neutral outcomes. In conclusion, most studies reported a favorable effect of Bifidobacterium and GOS on managing the symptoms of LI. No study has examined the effects of combined supplementation with Bifidobacterium and GOS in lactose intolerant subjects. Future research could examine if co-supplementation with Bifidobacterium and GOS is a more effective strategy to reduce the dairy discomfort in LI individuals.

Impairment of Mesenteric Perfusion as a Marker of Major Bleeding in Trauma Patients

The majority of potentially preventable mortality in trauma patients is related to bleeding; therefore, early recognition and effective treatment of hemorrhagic shock impose a cardinal challenge for trauma teams worldwide. The reduction in mesenteric perfusion (MP) is among the first compensatory responses to blood loss; however, there is no adequate tool for splanchnic hemodynamic monitoring in emergency patient care. In this narrative review, (i) methods based on flowmetry, CT imaging, video microscopy (VM), measurement of laboratory markers, spectroscopy, and tissue capnometry were critically analyzed with respect to their accessibility, and applicability, sensitivity, and specificity. (ii) Then, we demonstrated that derangement of MP is a promising diagnostic indicator of blood loss. (iii) Finally, we discussed a new diagnostic method for the evaluation of hemorrhage based on exhaled methane (CH₄) measurement. Conclusions: Monitoring the MP is a feasible option for the evaluation of blood loss. There are a wide range of experimentally used methodologies; however, due to their practical limitations, only a fraction of them could be integrated into routine emergency trauma care. According to our comprehensive review, breath analysis, including exhaled CH₄ measurement, would provide the possibility for continuous, non-invasive monitoring of blood loss.

Long-term Gastrointestinal Sequelae Following COVID-19: A Prospective Follow-up Cohort Study

BACKGROUND & AIMS

Coronavirus disease 2019 (COVID-19) is associated with long-term gastrointestinal sequelae; however, prospective longitudinal data are sparse. We prospectively studied the frequency, spectrum, and risk factors of post infection functional gastrointestinal disorders/disorders of gut-brain interaction (PI-FGID/DGBI) after COVID-19.

METHODS

Three hundred twenty cases with COVID-19 and 2 control groups, group A, 320 healthy spouses/family controls, and group B, 280 healthy COVID serology-negative controls, were prospectively followed up at 1, 3, and 6 months by using validated Rome IV criteria to evaluate the frequency of PI-FGID/DGBI.

RESULTS

Of 320 cases, at 1 month 36 (11.3%) developed FGID symptoms. Persistent symptoms were noted in 27 (8.4%) at 3 months and in 21 (6.6%) at 6 months. At 3 months, 8 (2.5%) had irritable bowel syndrome, 7 (2.2%) had functional diarrhea, 6 (1.9%) had functional dyspepsia, 3 (0.9%) had functional constipation, 2 (0.6%) had functional dyspepsia-IBS overlap, and 1 (0.3%) had functional abdominal bloating/distention. Among symptomatic individuals at 3 months, 8 (29.6%) were positive for isolated carbohydrate malabsorption, 1 (3.7%) was positive for post infection malabsorption syndrome, and 1 (3.7%) was positive for intestinal methanogen overgrowth. None of the healthy controls developed FGID up to 6 months of follow-up (P < .01). Predictive factors at 3 and 6 months were severity of infection (P < .01) and presence of gastrointestinal symptoms at the time of infection (P < .01).

CONCLUSIONS

COVID-19 led to significantly higher number of new onset PI-FGID/DGBI compared with healthy controls at 3 and 6 months of follow-up. If further investigated, some patients can be diagnosed with underlying malabsorption.

Clinical efficacy of Daikenchuto (DKT: TJ-100) for gastrointestinal symptoms in patients with a history of colon and rectosigmoid cancer surgery: a randomized crossover study

PURPOSE

This randomized crossover trial investigated the effects of Daikenchuto (DKT: TJ-100) on gastrointestinal symptoms of patients after colon and rectosigmoid cancer surgery.

METHODS

Among patients who had completed surgery for colon cancer, including rectosigmoid cancer, over 6 months ago, 20 who complained of gastrointestinal symptoms were enrolled. Subjects were randomly assigned to two sequences: sequences: A and B. In period 1, sequence A subjects were orally administered DKT, whereas sequence B subjects were untreated for 28 days. After a 5-day interval, in period 2, sequences A and B were reversed. Quality-of-life markers (GSRS and VAS), the Sitzmark transit study, the orocecal transit time (lactulose hydrogen breath test) and Gas volume score were evaluated before and after each period with findings compared between the presence of absence of DKT administration.

RESULTS

Between sequences, there were no significant differences in clinicopathological characters or any evaluations before randomization. There was no carryover effect in this crossover trial. The administration of DKT significantly ameliorated the GSRS in total, indigestion, and diarrhea, although the planned number of subjects for inclusion in this trial was not reached.

CONCLUSIONS

DKT may ameliorate subjective symptoms for postoperative patients who complain of gastrointestinal symptoms.

Effects of meditation on physiological and metabolic parameters in patients with type 2 diabetes mellitus "MindDM": study protocol for a randomized controlled trial

BACKGROUND

Sri Lanka is faced with the challenge of managing a large population with diabetes mellitus by 2030. Psychological stress plays a major role in disease outcome by exerting physiological, psychological and social effects on individuals with chronic disorders. Meditation-based interventions have positive effects on the management of stress and diabetes, which are mediated via modulation of neuro-humoral mechanisms and autonomic functions, among others. Mechanisms of bio-physiological effects of meditation are considered to be through reduction of stress hormones, improvement of insulin resistance and improvement of autonomic dysfunction.

METHODS

This study will be conducted as an open-label, randomized controlled clinical trial in the Faculty of Medicine, University of Colombo. The aim is to investigate the effects of meditation on glycaemic control and possible mechanisms of how meditation affects glycaemic control in patients with type 2 diabetes. The study was approved by the Ethics Review Committee of the Faculty of Medicine, University of Colombo (ERC/2019/094). Patients who are attending the professorial unit medical clinic with type 2 diabetes (172 in total) will be recruited based on inclusion-exclusion criteria. Patients who have never meditated or rarely meditated (less than once every three months) will be randomized using block randomization to meditation and waitlisted arms (1:1 allocation ratio). The meditation arm will undergo a mindfulness meditation program (selected after studying several meditation methods) conducted by a qualified instructor weekly for a period of 12 weeks in addition to usual care, while the waitlisted arm will only receive usual care. Daily meditation practices will be recorded in a diary. The primary outcome measure is HbA1c. Secondary outcome measures are fasting blood sugar, fructosamine, insulin resistance (calculated using fasting serum insulin), 24-h urinary cortisol, body mass index, cardiac autonomic reflex testing (Ewing's battery of tests) and orocecal transit time using hydrogen breath analysis. All these will be done prior to commencement of the intervention and after 3 months in both arms. Data will be analysed using SPSS V-23.

DISCUSSION

This study aims to identify the effect of mindfulness meditation on glycaemic control and the possible mechanisms (neuro humoral and autonomic functions) by which beneficial effects are mediated.

TRIAL REGISTRATION

Registered under Sri Lanka Clinical Trial Registry: SLCTR/2021/015 The Universal Trial Number (UTN) U1111-1266-8640.

Efficacy and Safety of a Novel Therapeutic of Natural Origin (NTN) in Adult Patients with Lactose Intolerance: A Multicenter, Randomized, Crossover, Double-Blind, Placebo-Controlled Study

Background: Film-forming substances, such as natural polysaccharides (NP) and pea proteins (PP), act as a protective barrier for treating various gastrointestinal conditions. We assessed the efficacy and safety of a novel therapeutic of natural origin (NTN) containing NP and PP for symptomatic treatment of lactose intolerance. Methods: In this multicenter, randomized, double-blind, parallel-group study, patients with lactose intolerance received NTN (n = 30) or placebo (n = 30) for 7 days, then the alternate treatment for 7 days. Patients rated their gastrointestinal symptoms using a 7-point Likert scale. The lactose hydrogen breath test was used to assess exhaled hydrogen. Results: NTN as primary or crossover treatment significantly improved patient-reported symptoms of bloating, distension, and abdominal pain. Abdominal pain also improved under primary treatment with placebo. Primary treatment with NTN, but not placebo, normalized mean exhaled hydrogen levels. In the group allocated initially to placebo, crossover to NTN attenuated the increase in hydrogen production. No treatment-related adverse effects were reported in either group. Conclusions: Subjective improvements in bloating, distension, and abdominal pain with NTN were supported by objective evidence of hydrogen production normalization. NTN appears to be a useful alternative to lactose avoidance or enzyme replacement in patients with lactose intolerance.

Validation of a modified cow's milk-related symptom score (CoMISS) for screening of lactose intolerance in adults

INTRODUCTION

Lactose intolerance (LI) is the failure to digest foods and beverages containing the lactose present in milk. LI can present by many digestive symptoms.

OBJECTIVE

To validate the modified CoMiSS score for prediction of LI, that was confirmed by a stool acidity test.

PATIENTS AND METHODS

A cross-sectional study, was conducted at Ain Shams University Hospitals/Gastrointestinal Clinics, and included one hundred adult participants during the period from December 2018 to December 2019. Enrolled patients had one or more gastrointestinal symptoms and were subjected to a stool acidity test (fecal PH test) as a reference test and modified CoMiSS as an index test.

RESULTS

The mean age of participants was 35.30 ± 10.714 years old; 55% were females, and their mean body mass index (BMI) was 23.08 ± 2.080 kg/m², with no significant relation between LI and patients` gender or BMI. Out of the studied participants 24% had positive stool PH, LI diagnosed according to modified CoMISS was present among 19% of them. The mean value of modified CoMISS Score was significantly higher in positive cases (12.37) compared to negative LI participants (2.33) as p < .001. Area under ROC Curve was 0.998, at the selected cut-off value 8, the sensitivity was 89.5% and specificity was 100% thus, levels of questionnaire scoring of 8 or higher would indicate presence of lactose intolerance.

CONCLUSION

Modified CoMiSS is a simple, fast, and easy-to-use tool that can predict LI, with a cut-off value of >8, the Area under the ROC Curve was 0.998, sensitivity 89.5%, and specificity was 100%.

Can Lactose Intolerance Be a Cause of Constipation? A Narrative Review

Lactose intolerance and constipation are common in children and impact everyday life, not only for patients but also their families. Both conditions can be comorbid with other diseases or form a part of their clinical presentation, but constipation is not usually associated with lactose intolerance. The typical symptoms of lactose intolerance include abdominal pain, bloating, flatus, diarrhoea, borborygmi, and less frequently nausea and vomiting. In approximately 30% of cases, constipation can be a symptom of lactose intolerance. Constipation is characterized by infrequent bowel movements, hard and/or large stools, painful defecation, and faecal incontinence, and is often accompanied by abdominal pain. This paper provides a narrative review on lactose intolerance, its epidemiology, pathogenesis, the correlation between lactose intolerance and constipation in children, and potential mechanisms of such association.

Highly Sensitive and Selective Detection of Hydrogen Using Pd-Coated SnO2 Nanorod Arrays for Breath-Analyzer Applications

We report a breath hydrogen analyzer based on Pd-coated SnO₂ nanorods (Pd-SnO₂ NRs) sensor integrated into a miniaturized gas chromatography (GC) column. The device can measure a wide range of hydrogen (1–100 ppm), within 100 s, using a small volume of human breath (1 mL) without pre-concentration. Especially, the mini-GC integrated with Pd-SnO₂ NRs can detect 1 ppm of H₂, as a lower detection limit, at a low operating temperature of 152 °C. Furthermore, when the breath hydrogen analyzer was exposed to a mixture of interfering gases, such as carbon dioxide, nitrogen, methane, and acetone, it was found to be capable of selectively detecting only H₂. We found that the Pd-SnO₂ NRs were superior to other semiconducting metal oxides that lack selectivity in H₂ detection. Our study reveals that the Pd-SnO₂ NRs integrated into the mini-GC device can be utilized in breath hydrogen analyzers to rapidly and accurately detect hydrogen due to its high selectivity and sensitivity.

Efficacy of Pro-Kinetic Agents in Type 2 Diabetes Mellitus Patients With Gastroparesis Using Lactulose Hydrogen Breath Testing: A Randomized Trial

Aim

The aim of the study was to determine the efficacy of prokinetic agents in diabetic gastroparesis patients.

Method

This was a randomized open-label trial conducted on 50 patients with type 2 diabetes experiencing diabetic gastroparesis, which was diagnosed with the lactulose hydrogen breath test. After randomization, all 50 patients were divided into four arms (cinitapride, metoclopramide, levosulpiride, and domperidone) of different prokinetics and followed up for four weeks; after which, repeat gastroparesis cardinal symptom index score and orocecal transit time were recorded in order to assess the response to the treatment.

Result

There was no statistically significant difference among the four groups in terms of all the baseline characteristics except for gender (p=0.032). The follow-up gastroparesis cardinal symptom index was collected for 50 patients but repeat orocecal transit time could be performed only in 37 patients. In all four groups, there was a statistically significant (p<0.05) improvement in terms of orocecal transit time and gastroparesis cardinal symptom index scores. But there was no statistically significant difference in relative efficacy amongst these study groups.

Conclusion

Our study showed statistically significant improvement with four prokinetics drugs in terms of gastroparesis cardinal symptom index score and orocecal transit time, but there was no statistically significant benefit of one prokinetic drug over the other. Our study showed promising results with regard to prokinetic use in diabetic gastroparesis.

The Short-Term Effects and Tolerability of Low-Viscosity Soluble Fibre on Gastroparesis Patients: A Pilot Clinical Intervention Study

Gastroparesis is a motility disorder that causes severe gastric symptoms and delayed gastric emptying, where the majority of sufferers are females (80%), with 29% of sufferers also diagnosed with Type-1 or Type-2 diabetes. Current clinical recommendations involve stringent dietary restriction and includes the avoidance and minimization of dietary fibre. Dietary fibre lowers the glycaemic index of food, reduces inflammation and provides laxation. Lack of dietary fibre in the diet can affect long-term gastrointestinal health. Our previously published rheological study demonstrated that "low-viscosity" soluble fibres could be a potentially tolerable source of fibre for the gastroparetic population. A randomised controlled crossover pilot clinical study was designed to compare Partially-hydrolysed guar gum or PHGG (test fibre 1), gum Arabic (test fibre 2), psyllium husk (positive control) and water (negative control) in mild-to-moderate symptomatic gastroparesis patients (requiring no enteral tube feeding). The principal aim of the study was to determine the short-term physiological effects and tolerability of the test fibres. In n = 10 female participants, post-prandial blood glucose, gastroparesis symptoms, and breath test measurements were recorded. Normalized clinical data revealed that test fibres PHGG and gum Arabic were able to regulate blood glucose comparable to psyllium husk, while causing far fewer symptoms, equivalent to negative control. The test fibres did not greatly delay mouth-to-caecum transit, though more data is needed. The study data looks promising, and a longer-term study investigating these test fibres is being planned.

The breath print represents a novel biomarker of malnutrition in pulmonary arterial hypertension: A proof of concept study

BACKGROUND

The breath print is a quantitative measurement of molecules in exhaled breath and represents a new frontier for biomarker identification. It is unknown whether this state-of-the-art, noninvasive method can detect malnutrition. We hypothesize that individuals with malnutrition will present with a distinguishable breath print.

METHODS

We conducted a retrospective chart review on patients with previously analyzed breath samples to identify malnutrition. Breath was analyzed by selected-ion flow-tube mass spectrometry. Registered dietitians conducted a retrospective chart review to collect malnutrition diagnoses and nutrition status indicators. Patients were categorized into one of four groups: pulmonary arterial hypertension (PAH), PAH with malnutrition (PAH-Mal), control, and control with malnutrition (Control-Mal), based on the malnutrition diagnosis present in the patient's chart. Principle component analysis was conducted to characterize the breath print. A logistic regression model with forward selection was used to detect the best breath predictor combination of malnutrition.

RESULTS

A total of 74 patients met inclusion criteria (PAH: 52; PAH-Mal: 10; control: 10; Control-Mal: 2). Levels of 1-octene (PAH-Mal, 5.1 ± 1.2; PAH, 12.5 ± 11.2; P = 0.005) and ammonia (PAH-Mal, 14.6 ± 15.8; PAH, 56.2 ± 64.2; P = 0.013) were reduced in PAH-Mal compared with PAH. The combination of 1-octene (P = 0.010) and 3-methylhexane (P = 0.045) distinguished malnutrition in PAH (receiver operating characteristic area under the curve: 0.8549).

CONCLUSIONS

This proof of concept study provides the first evidence that the breath print is altered in malnutrition. Larger prospective studies are needed to validate these results and establish whether breath analysis may be a useful tool to screen for malnutrition in the clinical setting.

Classification of gastric emptying and orocaecal transit through artificial neural networks

Classical quantification of gastric emptying (GE) and orocaecal transit (OCT) based on half-life time T$ _{50} $, mean gastric emptying time (MGET), orocaecal transit time (OCTT) or mean caecum arrival time (MCAT) can lead to misconceptions when analyzing irregularly or noisy data. We show that this is the case for gastrointestinal transit of control and of diabetic rats. Addressing this limitation, we present an artificial neural network (ANN) as an alternative tool capable of discriminating between control and diabetic rats through GE and OCT analysis. Our data were obtained via biological experiments using the alternate current biosusceptometry (ACB) method. The GE results are quantified by T$ _{50} $ and MGET, while the OCT is quantified by OCTT and MCAT. Other than these classical metrics, we employ a supervised training to classify between control and diabetes groups, accessing sensitivity, specificity, $ f_1 $ score, and AUROC from the ANN. For GE, the ANN sensitivity is 88%, its specificity is 83%, and its $ f_1 $ score is 88%. For OCT, the ANN sensitivity is 100%, its specificity is 75%, and its $ f_1 $ score is 85%. The area under the receiver operator curve (AUROC) from both GE and OCT data is about 0.9 in both training and validation, while the AUCs for classical metrics are 0.8 or less. These results show that the supervised training and the binary classification of the ANN was successful. Classical metrics based on statistical moments and ROC curve analyses led to contradictions, but our ANN performs as a reliable tool to evaluate the complete profile of the curves, leading to a classification of similar curves that are barely distinguished using statistical moments or ROC curves. The reported ANN provides an alert that the use of classical metrics can lead to physiological misunderstandings in gastrointestinal transit processes. This ANN capability of discriminating diseases in GE and OCT processes can be further explored and tested in other applications.

Gallbladder motility in children with celiac disease before and after gluten-free diet

Background

Gallbladder (GB) hypomotility has been reported in adults with celiac disease (CD), but there is no literature on GB dysfunction in children with CD. We aimed to study GB motility in children with CD, before and after a gluten-free diet (GFD), using ultrasonography (USG) and technetium-99 labeled mebrofenin hepatobiliary scintigraphy (HBS).

Methods

Children with newly diagnosed CD were enrolled and evaluated for GB ejection fraction (GBEF) using HBS and USG. Those with reduced GBEF on initial HBS were again evaluated after 6 months of strict GFD and the results were compared.

Results

Of the 50 children with CD (mean age 9±2.1 years, 54% boys), 16% (n=8) had a low GBEF at baseline (19±13%). These children had a significantly greater delay in diagnosis compared to those with normal GBEF (6.5±2.0 vs. 2.3±1.2 years, P<0.001). A significant improvement in GBEF was noted on HBS post GFD (74±12%1 vs. 9±13%, P<0.001). GBEF also improved significantly as assessed by USG parameters after GFD (P<0.001). The fasting GB volume decreased (5.7±1.4 vs. 10.2±2.6, P=0.002), with a significant improvement in percentage postprandial GB volume change (52±10.5% vs. 24±16.5%, P=0.007) compared to baseline pre-GFD values. Orocecal transit time was also increased in children with reduced GBEF.

Conclusions

GB function is impaired in at least 16% of children with CD at diagnosis and is reversible with GFD. GB dysfunction is significantly associated with a delayed diagnosis and may be a part of general gastrointestinal dysmotility.

Breath methane to hydrogen ratio as a surrogate marker of intestinal dysbiosis in head and neck cancer

Exhaled breath compounds can non-invasively detect head and neck squamous cell carcinoma (HNSCC). Here we investigated exhaled compounds related to intestinal bacterial carbohydrate fermentation. Fasting breath samples were collected into 3 litre FlexFoil PLUS bags from patients awaiting a biopsy procedure for suspected HNSCC. Samples were analysed using a Syft selected ion flow-tube mass spectrometer and a Quintron BreathTracker. Two tailed non-parametric significance testing was conducted with corrections for multiple imputations. 74 patients were diagnosed (histological) with HNSCC and 61 patients were benign (controls). The methane to hydrogen ratio was significantly different between cancer and non-cancer controls (p = 0.0440). This ratio increased with tumour stage with a significant difference between T1 and T4 tumours (p = 0.0259). Hydrogen levels were significantly higher in controls who were smokers (p = 0.0129), with no smoking dependent methane changes. There were no differences in short chain fatty acids between groups. Exhaled compounds of intestinal carbohydrate fermentation can detect HNSCC patients. These findings suggest a modified carbohydrate fermentation profile in HNSCC patients that is tumour stage and smoking status dependent.

Lactose Intolerance: What Your Breath Can Tell You

Lactose intolerance has seen recognized as a clinical syndrome characterized by pain, abdominal distention, flatulence, and diarrhea after the consumption of lactose. Lactose is a common disaccharide found in dairy that requires lactase-phlorizin hydrolase (LPH) to break down into glucose and galactose. A deficiency in this enzyme results in flora bacteria further along in the gastrointestinal tract (GI) tract to metabolize the excess lactose to numerous gases, including H₂. Recent studies show that the risk of symptoms after lactose ingestion depends on the dose of lactose, LPH expression, intestinal flora, and sensitivity of the gastrointestinal tract. Currently, there are several diagnostic tests that investigate the biological mechanism of lactose intolerance such as blood, biopsy, genetic, and breath tests. Due to its relatively low cost, availability, and non-invasiveness, the hydrogen breath test (HBT) has become a popular technology to aid in the diagnosis of many gastroenterological diseases, specifically lactose intolerance. Additionally, while administering the HBT there seems to be a lack of uniform criteria amongst the various studies, with many using their own guidelines, which may in turn cause inconsistency with the analysis of the results. With ever improving nanotechnology, novel approaches to expedite and lower the costs of the HBT has become an area of research with significant advancements.

Diagnostic Utility of Carbohydrate Breath Tests for SIBO, Fructose, and Lactose Intolerance

BACKGROUND

Unexplained bloating, gas, and pain are common symptoms. If routine tests are negative, such patients are often labeled as irritable bowel syndrome.

AIMS

To determine the diagnostic utility of breath tests that assess for small intestinal bacterial overgrowth (SIBO), fructose or lactose intolerance, and the predictive value of symptoms.

METHODS

Patients with gas, bloating, diarrhea, abdominal pain (≥ 6 months), and negative endoscopy and radiology tests were assessed with symptom questionnaires, glucose (75 g), fructose (25 g), or lactose (25 g) breath tests. Breath tests were categorized as positive when H₂ (≥ 20 ppm) or CH₄ (≥ 15 ppm) increased above baseline values or as hypersensitive when symptoms changed significantly without rise in H₂/CH₄ or as negative.

RESULTS

1230 patients (females = 878) underwent 2236 breath tests. The prevalence of SIBO was 33% (294/883), fructose intolerance was 34% (262/763), and lactose intolerance was 44% (260/590). Hypersensitivity was found in 16% and 9%, respectively, during fructose and lactose breath tests. Although gas (89%), abdominal pain (82%), and bloating (82%) were highly prevalent, pretest symptoms or their severity did not predict an abnormal breath test, but symptoms during the breath test facilitated diagnosis of SIBO, fructose, and lactose intolerance and hypersensitivity.

CONCLUSIONS

Approximately 45% of patients with unexplained gas and bloating had SIBO, fructose, or lactose intolerance; another 9-16% had visceral hypersensitivity. Pretest symptoms were poor predictors, but symptoms during the breath tests were useful. Breath tests are safe, provide significant diagnostic yield, and could be useful in routine gastroenterology practice.

Year 2020: A Snapshot of the Last Progress in Flexible Printed Gas Sensors

A review of recent advances in flexible printed gas sensors is presented. During the last years, flexible electronics has started to offer new opportunities in terms of sensors features and their possible application fields. The advent of this technology has made sensors low-cost, thin, with a large sensing area, lightweight, wearable, flexible, and transparent. Such new characteristics have led to the development of new gas sensor devices. The paper makes some statistical remarks about the research and market of the sensors and makes a shot of the printing technologies, the flexible organic substrates, the functional materials, and the target gases related to the specific application areas. The conclusion is a short notice on perspectives in the field.

Usefulness of the hydrogen breath test in patients with functional dyspepsia

Introduction

The pathogenesis of functional dyspepsia is complex and not well understood. Therefore, in this disease there should be considered involvement of different pathogenic factors, including intestinal bacteria.

Aim

To evaluate the results of the hydrogen breath test in relation to the clinical picture of functional dyspepsia.

Material and methods

The study included 40 healthy subjects (group I), 72 patients with postprandial distress syndrome (PDS, group II), and 84 patients with epigastric pain syndrome (EPS, group III). The diagnosis of functional dyspepsia was based on Rome Criteria IV. The urea breath test (13C-UBT) and lactulose hydrogen breath test (LHBT) were performed in all subjects. Patients with a positive urea breath test were excluded from the study. Patients with a positive LHBT test were assigned to antibiotic therapy (1200 mg daily for 14 days). Before treatment and 6 weeks after the end of antibiotic therapy the LHBT was performed, and severity of dyspeptic symptoms was assessed using a 10-points visual analogue scale.

Results

A positive LHBT test was found in 35 (48.6%) patients in the group with PDS, and in 40 (47.6%) patients with EPS (p > 0.05). A positive correlation between the results of the LHBT test and severity of dyspeptic symptoms was found in both group (p < 0.001). After treatment with rifaximin the mean LHBT result and the index of severity of dyspeptic complaints were significantly decreased (p < 0.001).

Conclusions

Quantitative and/or qualitative changes in the gut microbiota may be the cause of functional dyspepsia.

Rationally Designed PdAuCu Ternary Alloy Nanoparticles for Intrinsically Deactivation-Resistant Ultrafast Plasmonic Hydrogen Sensing

Hydrogen sensors are a prerequisite for the implementation of a hydrogen economy due to the high flammability of hydrogen-air mixtures. They are to comply with the increasingly stringent requirements set by stakeholders, such as the automotive industry and manufacturers of hydrogen safety systems, where sensor deactivation is a severe but widely unaddressed problem. In response, we report intrinsically deactivation-resistant nanoplasmonic hydrogen sensors enabled by a rationally designed ternary PdAuCu alloy nanomaterial, which combines the identified best intrinsic attributes of the constituent binary Pd alloys. This way, we achieve extraordinary hydrogen sensing metrics in synthetic air and poisoning gas background, simulating real application conditions. Specifically, we find a detection limit in the low ppm range, hysteresis-free response over 5 orders of magnitude hydrogen pressure, subsecond response time at room temperature, long-term stability, and, as the key, excellent resistance to deactivating species like carbon monoxide, notably without application of any protective coatings. This constitutes an important step forward for optical hydrogen sensor technology, as it enables application under demanding conditions and provides a blueprint for further material and performance optimization by combining and concerting intrinsic material assets in multicomponent nanoparticles. In a wider context, our findings highlight the potential of rational materials design through alloying of multiple elements for gas sensor development, as well as the potential of engineered metal alloy nanoparticles in nanoplasmonics and catalysis.

Decrease in exhaled hydrogen as marker of congestive heart failure

Objective

Hydrogen excretion is thought to be related to systemic antioxidation activity. H₂ selectively reduces the hydroxyl radical of free hydrogen (·OH), a highly cytotoxic form of reactive oxygen species, in cultured cells.

Methods

We investigated whether exhaled H₂ decreased during night sleep, reflected ·OH production and was associated with heart failure severity. We enrolled 108 patients with chronic heart failure (CHF) and 15 control participants without CHF. H₂ concentration was measured by gas chromatography in exhaled breath collected before sleep and in the morning after overnight fasting. Overnight change in H₂ concentration (ΔH₂) was calculated. Mitochondrial morphology evaluated by transmission electron microscopy in endomyocardial biopsies collected from 18 patients with dilated cardiomyopathy.

Results

ΔH₂ was significantly lower in patients with CHF compared with controls (−4.3±1.0 vs 2.0±2.1 ppm, p=0.030) and was positively correlated with cardiac index (CI; r = −0.285, p=0.003). Patients with a ΔH₂<0 ppm had a significantly lower CI compared with those who had a ΔH₂>0 ppm (2.85±0.61 vs 3.24±0.65 L/min/m², p=0.005). ΔH₂ was negatively correlated with both the percentage of vacuole-containing mitochondria and indices of cristae remodelling (r = −0.61, p=0.007).

Conclusions

Decrease in exhaled H₂ during night sleep was associated with CHF severity. ΔH₂ warrants investigation as marker of CHF severity.

Risk of small intestinal bacterial overgrowth in patients receiving proton pump inhibitors versus proton pump inhibitors plus prokinetics

Background and Aim

Intestinal dysmotility is considered a risk factor for small intestinal bacterial overgrowth (SIBO). Prokinetics improve intestinal motility and are often prescribed with proton pump inhibitors (PPIs) in patients with gastroesophageal reflux disease (GERD) and/or functional dyspepsia. The present study aimed to evaluate the prevalence of SIBO and the orocecal transit time (OCTT) in patients taking PPI compared with those taking PPI plus prokinetics.

Methods

The study is a single‐center, cross‐sectional study. Enrolled patients (with age > 12 years) were divided into two groups: patients taking PPIs for more than 3 months (Group A) and those taking PPIs with prokinetics for more than 3 months (Group B) for various indications. Lactulose breath test (LBT) for OCTT and glucose breath test (GBT) for SIBO were conducted for all patients.

Results

Of the 147 enrolled patients, SIBO was documented in 13.2% patients in Group A versus 1.8% in Group B, P = 0.018. Median OCTT in Group A was 130 (105–160) min compared with 120 (92.5–147.5) min in Group B (P = 0.010). Median OCTT among SIBO‐positive patients was 160 (140–172.5) min compared with SIBO‐negative patients, where it was 120 (103.75–150) min (P = 0.002). The duration and type of PPI used were not associated with the occurrence of SIBO in our study.

Conclusion

The use of prokinetics in patients on PPI may reduce the risk of SIBO by enhancing intestinal motility and may reduce SIBO risk associated with long‐term PPI use.

Hydrogen excretion in pediatric lactose malabsorbers: relation to symptoms and the dose of lactose

INTRODUCTION

Lactose malabsorption arises from lactase deficiency and may lead to lactose intolerance - gastrointestinal symptoms after lactose ingestion. Occurrence and severity of the symptoms are influenced by many factors, including the dose of lactose and the intensity of its colonic fermentation to short chain fatty acids and gases.

MATERIAL AND METHODS

The hydrogen breath test (HBT) after 30 g or 50 g of lactose was performed in 387 children. Further analysis included children who had a positive HBT result. The HBT parameters were net hydrogen concentration in each breath and total net hydrogen concentration during the HBT. The time of the first hydrogen rise was also calculated. HBT parameters were analyzed according to symptoms occurrence (lack or present), symptoms severity (lack, moderate or severe) and the dose of lactose (30 g or 50 g).

RESULTS

One hundred and six children (12.1 years, 46 boys) had a positive HBT result. Symptoms occurrence was positively related to net hydrogen concentration at 30 min, 60 min and 90 min (p < 0.001 at each time point), as well as to the total net hydrogen concentration (p < 0.001). There were no differences in hydrogen excretion between subjects with moderate and severe symptoms after lactose ingestion. Symptoms were more frequent in subjects given 50 g of lactose than in those given 30 g of lactose (79% vs. 47%, p = 0.003). In both dose groups symptoms occurrence was related to hydrogen excretion.

CONCLUSIONS

Symptoms occurrence is closely related to hydrogen excretion and to the dose of ingested lactose.

The effect of omeprazole treatment on the gut microflora and neutrophil function

BACKGROUND AND AIM

Proton pump inhibitors (PPIs) may increase the risk of Clostridium difficile infections. There are interactions between gut microbiota and innate immune cells including neutrophils. We evaluated the effect of treatment with omeprazole on the gut microflora and neutrophil function.

METHODS

In 50 patients, we evaluated the effect of 4-week omeprazole treatment (n=25 with 20mg per day and n=25 with 20mg twice daily) on intragastric pH, results of stool culture and lactulose hydrogen breath test (LHBT) and neutrophil function.

RESULTS

The treatment caused significant increase of the mean intragastric pH, especially in the group with 20mg omeprazole twice daily (from 2.05±0.59 to 5.06±1.6, P<0.001). In LHBT, the increase of hydrogen concentration was observed in higher percentage of patients with 20mg of omeprazole twice daily, compared to patients with the lower dose (42.1% vs 29.4%; ns). Four weeks of omeprazole treatment have caused considerable changes in stool culture results. Patients treated with higher dose of omeprazole have had some tendency to decrease diversity of colonic microflora in comparison with patients treated with the lower dose of omeprazole. Treatment with omeprazole did not result in C. difficile positive stool culture and had no significant effect on neutrophil function.

CONCLUSIONS

Omeprazole treatment have caused considerable changes in stool culture results. Patients treated with the higher dose had some tendency to decreased diversity of colonic microflora and towards changes in fermenting bacteria of the gut. The potential effect of omeprazole on gut microflora does not depend on neutrophil function deterioration.

Established and emerging methods for assessment of small and large intestinal motility

BACKGROUND

Gastrointestinal symptoms are common in the general population and may originate from disturbances in gut motility. However, fundamental mechanistic understanding of motility remains inadequate, especially of the less accessible regions of the small bowel and colon. Hence, refinement and validation of objective methods to evaluate motility of the whole gut is important. Such techniques may be applied in clinical settings as diagnostic tools, in research to elucidate underlying mechanisms of diseases, and to evaluate how the gut responds to various drugs. A wide array of such methods exists; however, a limited number are used universally due to drawbacks like radiation exposure, lack of standardization, and difficulties interpreting data. In recent years, several new methods such as the 3D-Transit system and magnetic resonance imaging assessments on small bowel and colonic motility have emerged, with the advantages that they are less invasive, use no radiation, and provide much more detailed information.

PURPOSE

This review outlines well-established and emerging methods to evaluate small bowel and colonic motility in clinical settings and in research. The latter include the 3D-Transit system, magnetic resonance imaging assessments, and high-resolution manometry. Procedures, indications, and the relative strengths and weaknesses of each method are summarized.

Is Hydrogen Breath Test with Lactulose Feasible for Measuring Gastrocecal Transit in Critically Ill Children? Pilot Study about Modification of the Technique

Introduction. Gastrocecal transit time (GCTT) can be measured by exhaled hydrogen after lactulose intake (lactulose-eH₂ test). The objectives were to assess whether it is possible to carry out this test in critically ill children with and without mechanical ventilation (MV) and to analyze whether the results are consistent with clinical findings. Methods. Patients admitted to the Pediatric Intensive Care Unit (PICU) for more than 3 days were included. Those with gastrointestinal disease prior to admission were excluded. A modified technique to obtain eH₂ from the ventilator tubes was performed. Results. Sixteen patients (37.5% boys) with a median age of 19 (5-86.5) months were included. Five patients (31.2%) were breathing spontaneously but lactulose-eH₂ test could not be performed while it could be performed successfully in the 11 patients with MV. Seven patients (63.3%) did not show an eH₂ peak. The other 4 showed a median time of 130 min (78.7-278.7 min) from lactulose intake to a 10 ppm eH₂ peak. Children with an eH₂ peak had intestinal movements earlier [6.5 (1.5-38.5) versus 44 (24-72) hours p = 0.545]. Conclusion. Although the designed adaption is useful for collecting breath samples, lactulose-eH₂ test may not be useful for measuring GCTT in critically ill children.

Outcome of breath tests in adult patients with suspected small intestinal bacterial overgrowth

AIM

The aim was to investigate breath test outcomes in patients with suspected SIBO and indicative symptoms of SIBO, diagnosed by breath testing.

BACKGROUND

Breath testing is used to detect small intestinal bacterial overgrowth (SIBO) by measuring hydrogen and methane produced by intestinal bacteria.

METHODS

This retrospective cross sectional study included 311 patients with gastrointestinal symptoms who underwent the breath test for evaluation of SIBO at Celiac Disease Center at Columbia University, New York, in 2014-2015. The patients were divided into two groups based on the physician's choice: lactulose breath test group (72%) and glucose breath test group (28%). Among them, 38% had a history of celiac disease or non-celiac gluten sensitivity.

RESULTS

In total, 46% had a positive breath test: 18% were positive for methane, 24 % positive for hydrogen and 4% positive for both gases (p=0.014). Also, 50% had a positive lactulose breath result and 37% had a positive glucose breath result (p=0.036). The most common symptom for performing the breath test was bloating and the only clinical symptom that significantly showed a positive glucose breath test was increased gas (p=0.028).

CONCLUSION

Lactulose breath test was more often positive than glucose breath test. Positivity for hydrogen was more common than methane. Bloating was the most frequently perceived symptom of the patients undergoing the breath test but the only statistically significant clinical symptom for a positive glucose breath test was increased gas. Furthermore, the results showed that there was no significant association between positive breath test result and gender, age, non-celiac gluten sensitivity or celiac disease.

Higher visceral to subcutaneous fat ratio is associated with small intestinal bacterial overgrowth

BACKGROUND AND AIMS

There is a lack of studies evaluating the association between small intestinal bacterial overgrowth (SIBO) and abdominal fat. The aim of this study was to evaluate whether visceral fat area (VFA), subcutaneous fat area (SFA) or visceral to subcutaneous fat ratio (VFA/SFA ratio) were associated with SIBO.

METHODS AND RESULTS

In this case-control study, 152 eligible patients submitted to glucose hydrogen/methane breath test who also had computed tomography (CT) of the abdomen performed were included. Clinical and demographic information was obtained. VFA and SFA were measured using Image J software at lumbar 3 level on CT cross-sectional image of the 152 patients included in this study, 68 patients (44.7%) tested positive for SIBO. In the univariate analysis, the presence of SIBO was associated with older age (65.2 ± 1.5 vs. 59.3 ± 1.5, p = 0.007); type 2 diabetes mellitus (33.8% vs. 17.9%; p = 0.019); hypertension (63.2% vs. 39.3%; p = 0.003); metabolic syndrome (85.3% vs. 64.3%; p = 0.003); and higher VFA/SFA ratio (1.0 ± 0.1 vs. 0.7 ± 0.1; p < 0.001). In multivariate analysis, metabolic syndrome (odds ratio [OR]: 2.5; 95% confidence interval [CI]: 1.1-5.7; p = 0.035) and higher VFA/SFA ratio (OR: 3.3; 95% CI: 1.6-7.2; p = 0.002) remained independently associated with SIBO.

CONCLUSION

The presence of SIBO was found to be associated with high VFA/SFA ratio measured from cross-sectional CT image.

The effects of the DDS-1 strain of lactobacillus on symptomatic relief for lactose intolerance - a randomized, double-blind, placebo-controlled, crossover clinical trial

BACKGROUND

Lactose intolerance is a form of lactose maldigestion where individuals experience symptoms such as diarrhea, abdominal cramping, flatulence, vomiting and bowel sounds following lactose consumption. Lactobacillus acidophilus is a species of bacteria known for its sugar fermenting properties. Preclinical studies have found that Lactobacillus acidophilus supplementation may assist in breaking down lactose; however, no human clinical trials exist evaluating its efficacy in alleviating symptoms related to lactose intolerance.

OBJECTIVE

The aim of this randomized, double-blind, placebo-controlled, crossover study was to evaluate the effect of a proprietary strain of Lactobacillus acidophilus on relieving discomfort related to lactose intolerance.

METHODS

The study enrolled healthy volunteers between 18 and 75 years of age who complained of lactose intolerance. Screening visits included a lactose challenge visit to confirm eligibility based on a score of 10 or higher on subjective assessment of the following symptoms after lactose challenge: diarrhea, abdominal cramping, vomiting, audible bowel sounds, flatulence, and overall symptoms. Qualified subjects participated in a 2-arm crossover design, with each arm consisting of 4 weeks of intervention of either active or placebo product, with a 2-week washout period during crossover. The study product consisted of the DDS-1 strain of Lactobacillus acidophilus (Nebraska Cultures, Walnut Creek, California). The placebo was formulated from maltodextrin. Study participants were instructed to take the product once daily for 4 weeks. Data collected included subjective symptom scores related to lactose intolerance.

RESULTS

Longitudinal comparison between the DDS-1 group and placebo group demonstrated statistically significant reductions in abdominal symptom scores during the 6-h Lactose Challenge at week 4 for diarrhea (p = 0.033), abdominal cramping (p = 0.012), vomiting (p = 0.0002), and overall symptom score (p = 0.037). No adverse events were reported.

CONCLUSIONS

The present study has found that this unique DDS-1 strain of Lactobacillus acidophilus, manufactured by Nebraska Cultures, is safe to consume and improves abdominal symptom scores compared to placebo with respect to diarrhea, cramping, and vomiting during an acute lactose challenge.

Small bowel bacterial overgrowth in patients with irritable bowel syndrome: the first study in iran

BACKGROUND Small intestinal bacterial overgrowth (SIBO) may have a role in the pathophysiology of irritable bowel syndrome (IBS). So, the aim of this study was to assess the association between SIBO and IBS by using glucose breath test (GBT) in Kerman city as the first study in Iranian population. METHODS 107 patients with IBS and 107 healthy individuals were enrolled in our study. All the participants underwent GBT. A peak of H2 values >20 p.p.m above the basal value after glucose ingestion was considered suggestive of SIBO. SPSS software version 17 was used for data analysis. P value < 0.05 was considered as statistically significant. RESULTS Of the 107 patients with IBS, 40 had positive GBT (37.4%) compared with 14 (12.1%) out of the 107 control participants(p< 0.001). Dominant symptoms in patients with IBS were diarrhea in 36(33.6%), constipation in 12(11.2%), abdominal pain in 22(20.6%), bloating in 28(26.2%), and change in bowel habit in 9(8.4%) patients. There was not statistically significant difference among any of this IBS subgroups and positive GBT (p=0.44). CONCLUSION There is a positive association between IBS and SIBO. We suggest a Placebo-controlled bacterial eradication study for identifying the role of SIBO in IBS.