Accuracy of Anorectal Manometry to Detect the Rectoanal Inhibitory Reflex in Children: Awake Versus Under General Anesthesia.

OBJECTIVES: Our objective was to investigate if there is a difference in the detection of the rectoanal inhibitory reflex (RAIR) when an anorectal manometry (ARM) is performed awake or under general anesthesia. METHODS: A retrospective review of ARM studies was performed to identify children who had undergone ARMs both while awake and under general anesthesia. We compared ARM outcomes including the detection of the RAIR and anal canal resting pressure. RESULTS: Thirty-four children had received ARMs both while awake and under general anesthesia (53% female, median age at first ARM 7.5 years [range 3-18 years]). In 9 of 34 (26%) children the RAIR was solely identified during ARM under general anesthesia and not during ARM while awake. In 6 of 9 (66%) this was unrelated to the balloon volumes used during balloon inflations. In 4 of 34 (12%) children, assessment of the RAIR was inconclusive during ARM under general anesthesia due to too low, or loss of anal canal pressure. In 2 of those children, ARMs while awake showed presence of a RAIR. Anal canal resting pressures were higher during ARM while awake versus ARM under general anesthesia (median 70 [interquartile range, IQR 59-85] vs 46 mmHg [IQR 36-65] respectively, P < 0.001). CONCLUSIONS: General anesthesia may affect the detection of a RAIR in 2 ways. On the one hand, it may facilitate better visualization in children in whom a RAIR could not be visualized while awake. On the other hand, it may cause a loss of anal canal pressure resulting in an inconclusive test result.

A Retrospective Review of Baclofen Treatment for Children with Rumination Syndrome at a Single Center.

BACKGROUND: Baclofen can decrease rumination frequency in adults with rumination syndrome. Outcomes of baclofen treatment in children with rumination syndrome have not been described. The aim of this study was to examine the safety and efficacy of baclofen in children with rumination syndrome in combination with behavioral therapy at a single center. METHODS: We performed a retrospective review of children aged 0-18 years with rumination syndrome based on Rome criteria and prescribed baclofen by a pediatric gastroenterologist at the Nationwide Children's Hospital, Columbus, Ohio, USA, between 2012 and 2019. Children without follow-up data or who were prescribed baclofen for other symptoms were excluded. RESULTS: We identified 44 children with rumination syndrome who were prescribed baclofen by a pediatric gastroenterologist. Seventeen either did not have follow-up data or never started the medication. We included 27 patients in the study: 22 (81.5%) female, median age 14.5 years (range 10-18 years) and 100% Caucasian. Twenty patients (74%) received baclofen 5 mg and seven patients (26%) received baclofen 10 mg three times daily. Most patients received behavioral therapy and baclofen simultaneously. Thirteen patients (48%) reported improvement in symptoms, primarily a decrease in rumination frequency, at their first follow-up visit. Regurgitation frequency per week decreased after starting baclofen (p < 0.05). One patient experienced dizziness. No other side effects were reported. CONCLUSION: Nearly half of our patients with rumination syndrome improved after baclofen. It was well tolerated with minimal side effects. This suggests that baclofen in addition to behavioral therapy can improve symptoms of rumination syndrome. Prospective, controlled studies in a larger cohort of children with rumination syndrome are needed to confirm these findings.

Anal Botulinum Toxin in Children with Hirschsprung Disease and Functional Constipation: A Prospective Cohort study.

INTRODUCTION: Anal sphincter botulinum toxin injections (BTIs) are used in the treatment of children with severe defecation disorders, including Hirschsprung disease (HD) and functional constipation (FC). Our objective was to evaluate the outcomes of BTI in these children. MATERIALS AND METHODS: We performed a prospective cohort study of children undergoing BTI from July 2018 to December 2018. We recorded perceived effect of the BTI, including effectiveness ranging from 0 (not at all effective) to 4 (extremely effective). In addition, we recorded symptoms and the Cleveland Clinic Constipation Score (CCCS). Data were collected at baseline and at 2 weeks, 2 months, and 4 months post-injection. RESULTS: Forty-two children (HD = 25, FC = 17) were included in the study (median age 4.3 years, IQR 2.4-7.2, 52% male). Twenty-two (88%) children with HD and eight (47%) children with FC had previously undergone a BTI. BTIs were perceived effective in 16 (76%) and 12 (71%) children with HD and eight (47%) and seven (47%) children with FC at 2-week and 2-month follow-up, respectively. Effectiveness was not rated differently between groups except at the 2-month follow-up, when patients with HD rated the BTI more effective compared to those with FC (median 2 [HD] vs. median 1 [FC], p = 0.022). Over the course of the study, 17/39 (44%) children reported self-limiting adverse effects such as fecal incontinence and pain at the injection site. CONCLUSION: Anal sphincter BTIs can be effective in the treatment of constipation in both HD and FC patients.

Do we need an extra dimension? A pilot study on the use of three-dimensional anorectal manometry in children with functional constipation.

BACKGROUND: Recently, a new high-definition (or three-dimensional "3D") high-resolution anorectal manometry (3D-ARM) catheter has been introduced. This catheter allows for a more detailed visualization of the anal canal. However, its clinical utility and tolerability in children with constipation are unknown. Our primary objective was to evaluate the agreement between findings from solid-state high-resolution anorectal manometry (HR-ARM) and 3D-ARM. Secondary objectives were to investigate if 3D-ARM has additional value over HR-ARM and to evaluate patient and provider experience. METHODS: Prospective pilot study including children (8-18 years of age) with functional constipation scheduled for anorectal manometry. Children underwent HR-ARM and 3D-ARM consecutively. We compared manometry results of both procedures and collected data on patient and provider experience via self-developed questionnaires. KEY RESULTS: Data of ten patients were analyzed (60% female, median age 14.9 years). In the majority of patients, ARMs were performed awake (n = 8, 80%). In two patients, the recto-anal inhibitory reflex (RAIR) was visualized during HR-ARM but not during 3D-ARM. Anal canal resting pressures were significantly higher during 3D-ARM compared to HR-ARM (median 77 mmHg [IQR 59-94] vs. 69 mmHg [IQR 51-91], respectively, p = 0.037). No significant anatomical or muscular abnormalities were visualized during the 3D-ARM. The majority of children identified the 3D-ARM as the more unpleasant (5/7 [71%]) and more painful procedure (6/7 [86%]) and therefore preferred the HR-ARM (4/7 [57%]). CONCLUSIONS & INFERENCES: In our patient sample, 3D-ARM was associated with more discomfort without providing more useful information and even resulted in an inconsistent visualization of the RAIR.

The Use of Linaclotide in Children with Functional Constipation or Irritable Bowel Syndrome: A Retrospective Chart Review.

BACKGROUND: Linaclotide is a well-tolerated and effective agent for adults with functional constipation (FC) or irritable bowel syndrome with constipation (IBS-C). However, data in children are lacking. The aim of this study is to examine the efficacy and safety of linaclotide in children. METHODS: We performed a retrospective review of children < 18 years old who started linaclotide at our institution (Nationwide Children's Hospital, Columbus, Ohio). We excluded children already using linaclotide or whom had an organic cause of constipation or abdominal pain. We recorded information on patient characteristics, medical and surgical history, symptoms, clinical response, course of treatment, and adverse events at baseline, first follow-up, and after 1 year of linaclotide use. A positive clinical response was based on the physician's global assessment of symptoms at the time of the visit as documented. RESULTS: We included 93 children treated with linaclotide for FC (n = 60) or IBS-C (n = 33); 60% were female; median age was 14.7 years (IQR 13.2-16.6). Forty-five percent of patients with FC and 42% with IBS-C had a positive clinical response at first follow-up a median of 2.5 and 2.4 months after starting linaclotide, respectively. Approximately a third of patients experienced adverse events and eventually 27% stopped using linaclotide due to adverse events. The most common adverse events were diarrhea, abdominal pain, nausea, and bloating. CONCLUSION: Nearly half of children with FC or IBS-C benefited from linaclotide, but adverse events were relatively common. Further prospective, controlled studies are needed to confirm these findings and to identify which patients are most likely to benefit from linaclotide.

The not-so-rare absent RAIR: Internal anal sphincter achalasia in a review of 1072 children with constipation undergoing high-resolution anorectal manometry.

BACKGROUND: Our objective is to describe the prevalence of patients with internal anal sphincter achalasia (IASA) without Hirschsprung disease (HD) among children undergoing anorectal manometry (ARM) and their clinical characteristics. METHODS: We performed a retrospective review of high-resolution ARM studies performed at our institution and identified patients with an absent rectoanal inhibitory reflex (RAIR). Clinical presentation, medical history, treatment outcomes, and results of ARM and other diagnostic tests were collected. We compared data between IASA patients, HD patients, and a matched control group of patients with functional constipation (FC). KEY RESULTS: We reviewed 1,072 ARMs and identified 109 patients with an absent RAIR, of whom 28 were diagnosed with IASA. Compared to patients with FC, patients with IASA had an earlier onset of symptoms and were more likely to have abnormal contrast enema studies. Compared to patients with HD, patients with IASA were more likely to have had a normal timing of meconium passage, a later onset of symptoms, and were diagnosed at an older age. At the latest follow-up, the majority of patients diagnosed with IASA (54%) were only using oral laxatives. Over half of patients with IASA had been treated with anal sphincter botulinum toxin injection, and 55% reported a positive response. CONCLUSIONS AND INFERENCES: Patients diagnosed with IASA may represent a more severe patient population compared to patients with FC, but have a later onset of symptoms compared to patients with HD. They may require different treatments for their constipation and deserve further study.