This study aimed to evaluate gastric accommodation in pediatric patients with functional constipation using the water load test.

This was a cross-sectional case-control study. Herein, the water load test results of children aged >4 years with functional constipation referred to a Pediatric Gastroenterology Outpatient Clinic (functional constipation group) were compared with those of a control group (without functional constipation or chronic abdominal pain) recruited from two public schools. Clinical manifestations outlined in the Rome IV criteria were used to diagnose functional constipation. Water load tests were performed after 3 h of fasting. For the test, the participants were asked to drink as much water as possible in 3 min.

A total of 36 patients and 77 students were included in the functional constipation and control groups, respectively. There was no significant difference in age between the groups (8.6 ± 2.3 years and 8.8 ± 1.8 years in the functional constipation and control groups, respectively). The water load test showed intake volumes of 390 ± 245 mL and 528 ± 219 mL in the functional constipation and control groups, respectively (p = 0.001). The maximum volume in the water load test correlated with the 24 h daily intake of energy (rS = +0.42, p = 0.012), protein (rS = +0.48, p = 0.004), and water (rS = +0.39, p = 0.020) only in the group with functional constipation.

According to the water load test, gastric accommodation was impaired in children with severe functional constipation. The impairment of gastric accommodation in children with severe functional constipation is related to food intake.

We hypothesize that patients with functional gastrointestinal disorders (FGID) drink less water volume than healthy subjects during water load test. We evaluated and compared the water load test in students with and without FGID using the Rome III questionnaire.

We performed the water load test in 142 students from two schools in Colombia. Students were diagnosed using the Spanish version of the Rome III questionnaire. Students drank water ad libitum for 3 min or until pain, satiety, or vomiting occurred. We correlated anthropometric variables with water volumes drunk. We recorded symptoms like pain and nausea, before and after the water load test.

We evaluated 142 students, with a mean age of 12.1 ± 0.2 years and 59.9% girls. Mean water volume drunk was 459 ± 22 mL. There was no significant difference between water volume drunk by students with and without FGID (466 ± 36 vs. 453 ± 27 mL, p = 0.108). We found a significant correlation between water volume drunk and gender, age, weight, height, and body mass index.

Students with and without FGID ingest similar volumes of water. Test adverse effects are minimal, and the test is safe to perform and well tolerated.

Paediatric functional abdominal pain disorders, currently referred to as disorders of gut-brain interaction, comprise irritable bowel syndrome, functional dyspepsia, abdominal migraine and functional abdominal pain not otherwise specified, as defined by the Rome IV diagnostic criteria. Functional abdominal pain disorders are common disorders with a prevalence of 3-16% depending on country, age and sex. A greater understanding of aetiopathogenesis and pathophysiology is emerging and includes intestinal components (inflammation, motility and the microbiota), central factors (psychological aspects, sensitization and/or differences in connectivity or activity of certain brain regions) as well as extrinsic factors (infections). In particular, the timing of disruption of the microbiota-gut-brain axis seems to be important. Diagnosis is challenging but is primarily based on clinical symptoms and exclusion of other organic causes, with an emphasis on avoiding unnecessary invasive diagnostic procedures. The available pharmacological interventions are limited in children and, therefore, management has focused on combined approaches, including mind-targeted interventions (hypnotherapy and cognitive behavioural therapy), diet (probiotics) and percutaneous electrical nerve field stimulation. The evidence for their clinical efficacy, although limited, is favourable, with positive impacts on symptoms and overall quality of life. The coming decades hold promise for improved understanding and management of these enigmatic disorders.

In order to develop effective weight management strategies, it is important to identify factors that influence energy intake. Portion size has been discussed as one such factor. To date, most studies focusing on the relationship between portion size, energy intake, and weight have analyzed questionnaire data and 24-h records. In this study, we assessed the onset of satiety using the water-load test in normal-weight and obese children and adolescents.

60 obese and 27 normal-weight children and adolescents aged between 9 and 17 years participated in the water load test which involved drinking water for 3 min or until feeling full. The amount of water consumed was recorded.

Obese children and adolescents drank 20% more water until the onset of satiety when compared with normal-weight participants (478 ± 222 ml vs. 385 ± 115 ml, P < 0.05).

Obese children and adolescents need to ingest greater volumes to feel full which may predispose toward the consumption of larger portion sizes. This may easily lead to overeating if predominantly energy-dense foods are consumed. A reduction in energy-dense foods in the diet of obese children and adolescents appears to be a necessary strategy for managing body weight.

Use of experimental pain is vital for addressing research questions that would otherwise be impossible to examine in the real world. Experimental induction of pain in children is highly scrutinized given the potential for harm and lack of direct benefit to a vulnerable population. However, its use has critically advanced our understanding of the mechanisms, assessment and treatment of pain in both healthy and chronically ill children. This article introduces various experimental pain modalities, including the cold pressor task, the water load symptom provocation test, thermal pain, pressure pain and conditioned pain modulation, and discusses their application for use with children and adolescents. It addresses practical implementation and ethical issues, as well as the advantages and disadvantages offered by each task. The incredible potential for future research is discussed given the array of experimental pain modalities now available to pediatric researchers.

Functional abdominal pain (FAP) and irritable bowel syndrome (IBS) are both associated with recurrent abdominal pain and are among the most commonly diagnosed medical problems in pediatrics. The majority of patients with mild complaints improve with reassurance and time. For a distinct subset of patients with more severe and disabling illness, finding effective treatment for these disorders remains a challenge. Based on the biopsychosocial model of functional disease, the Rome III criteria have helped frame FAP and IBS in terms of being a positive diagnosis and not a diagnosis of exclusion. However, the lack of a single, proven intervention highlights the complex interplay of pathologic mechanisms likely involved in the development of childhood FAP and IBS and the need for a multidisciplinary, integrated approach. This article discusses the epidemiology, proposed mechanisms, clinical approach and therapeutic options for the management of FAP and IBS in children and adolescents.

Alteration in autonomic function has been implicated as a possible pathophysiologic mechanism in functional dyspepsia (FD) in adults.

This was a two-part study. For the first part of the study, nine children with FD and 28 controls underwent heart rate variability (HRV) analysis for 30 min baseline and for 60 min following a test meal. For the second part of the study, eight children with FD and 26 controls underwent HRV analysis for 30 min baseline and for 60 min following rapid water loading. HRV analysis yielded measures for power in the high frequency (HF) band (vagal activity), power in the low frequency (LF) band (mainly sympathetic activity), and LF/HF (sympathovagal balance).

HRV parameters did not differ between FD patients and controls in either baseline period or following water loading. Following the meal, HF was higher and LF and LF/HF were lower in FD patients as compared to controls. Baseline LF/HF was positively correlated with the water load volume in controls and negatively correlated with the water load volume in FD patients.

FD in children is associated with an abnormal autonomic response best demonstrated following a meal. The relationship between baseline sympathovagal balance and water load volume in FD patients is distinctly different from the relationship in control children.

The aim of this study was to investigate the correlation of gastric myoelectrical and autonomic activities in healthy children. Simultaneous recordings of electrogastrography (EGG) and electrocardiogram (ECG) were performed in healthy children before and after a solid meal and water loading respectively. The autonomic activity was assessed by spectral analysis of the heart rate variability (HRV). The solid meal resulted in an increase in EGG-dominant frequency (2.92 cpm vs 3.16 cpm, P < 0.05), dominant power (46.9 dB vs 53.7 dB, P < 0.05) and percentage normal slow waves (81.9%vs 89.0%, P < 0.05), while only dominant power increased following water loading. Power in the low-frequency band of HRV (LF) was significantly increased and power in the high-frequency band of HRV (HF) significantly decreased following the solid meal. Postprandial LF was positively and HF negatively correlated with the postprandial increase in EGG-dominant power. Water loading was not associated with any significant changes in HRV parameters. These results suggest that both vagal and sympathetic pathways are involved in modulation of gastric myoelectrical activity.