Bowel perforation and anal ventriculoperitoneal shunt migration: A systematic review

Background

One of the most feared complications of hydrocephalus is shunt migration. Although rare, bowel migration is the most commonly encountered type of migration. The relatively high frequency of this occurrence allowed us to gather a substantial number of reports for study.

Objectives

The aim of this study was to better understand this complication and aid in decreasing its incidence.

Methods

The PubMed and Scopus databases were searched for cases of anal shunt migration. In total, 49 records describing 56 clinical cases were included in this review. Additionally, we present and include the clinical case of a patient managed by our team; therefore, 57 cases were included in this study. Relevant parameters were collected, organized, analyzed, and discussed. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement from 2009.

Results

Extrusion through the anus was observed in 82% of cases, 68% of which were in males. The age range varied from 1 month to 75 years. Congenital hydrocephalus was the etiology in 66% of cases. The time interval between shunt insertion and migration varied from 12 days to 19 years. In 70% of patients, the tube was pulled out through the anus, whereas a laparotomy or laparoscopy was used in 14% of cases. Infectious complications were noted in 35% of patients. The overall outcome was mostly favorable; two patients died as a complication of the migration.

Conclusions

Bowel and anal shunt migration is a relatively rare complication occurring predominantly within the initial weeks after the initial surgery. This condition leads to infectious complications, which can potentially be life-threatening. Urgent management is required, and in most cases, the removal of the shunt through the anus is sufficient. Early intervention generally results in favorable outcomes.

Constipation in transverse myelitis

Transverse myelitis is an extremely rare neuroinflammatory disorder. About half of the affected patients develop paraplegia associated with urinary and bowel dysfunction. The bowel dysfunction is thought to be benign and is usually managed with dietary management and laxatives. We report a case of a man in his 60s presenting with transverse myelitis and the acute disease course complicated with treatment refractory intestinal dysfunction resulting in intestinal perforation, eventually leading to his death. Thus, this case helps us weigh the fact that intestinal dysfunction in the case of transverse myelitis is not always benign but can lead to deadly outcomes as well.

Gut bless you: The microbiota-gut-brain axis in irritable bowel syndrome

Irritable bowel syndrome (IBS) is a common clinical label for medically unexplained gastrointestinal symptoms, recently described as a disturbance of the microbiota-gut-brain axis. Despite decades of research, the pathophysiology of this highly heterogeneous disorder remains elusive. However, a dramatic change in the understanding of the underlying pathophysiological mechanisms surfaced when the importance of gut microbiota protruded the scientific picture. Are we getting any closer to understanding IBS' etiology, or are we drowning in unspecific, conflicting data because we possess limited tools to unravel the cluster of secrets our gut microbiota is concealing? In this comprehensive review we are discussing some of the major important features of IBS and their interaction with gut microbiota, clinical microbiota-altering treatment such as the low FODMAP diet and fecal microbiota transplantation, neuroimaging and methods in microbiota analyses, and current and future challenges with big data analysis in IBS.

Meeting the Motility Educational Requirements of the Gastroenterology Trainee in the 21st Century

BACKGROUND

Gastrointestinal (GI) motility and functional disorders comprise over two-third of referrals to GI specialists yet training programs are disproportionately focused on endoscopy, inflammatory bowel disease and liver disease. Trainees at many centres receive minimal or no formal training in motility disorders and have little or no exposure to motility testing. Our purpose was to develop an educational intervention to address this learning need.

METHODS

We designed a formal training program comprised of didactic sessions, workshops and hands-on motility sessions with live demonstrations designed to be held over the course of a weekend. Faculty for the course were experienced GI motility experts from across Canada. Resident trainees from all Canadian GI fellowship programs were invited to attend. Pre- and post-tests were administered to measure the baseline learning needs and the impact of the program. Course evaluations were completed by attendees.

RESULTS

Three annual courses were offered over the past 3 years. Both adult and paediatric gastroenterology trainees attended the programs. The majority of training programs from Canada were represented. Baseline testing of attendees revealed a fundamental lack of understanding of GI motility concepts and their clinical implications. Postcourse test scores demonstrated a significant improvement in motility knowledge. Course evaluations of the content and faculty presentations received uniformly positive reviews.

CONCLUSIONS

There is a pervasive lack of clinical knowledge of GI motility among Canadian GI subspecialty trainees. A focused weekend intensive course is one step in addressing this learning need.

Frequency and burden of gastrointestinal symptoms in familial dysautonomia

PURPOSE

Familial dysautonomia (FD) is a rare hereditary sensory and autonomic neuropathy (HSAN-3) that is clinically characterized by impaired pain and temperature perception and abnormal autonomic function. Patients with FD have gastrointestinal dysmotility and report a range of gastrointestinal symptoms that have yet to be systematically evaluated. The aim of this study was to establish the frequency and severity of gastrointestinal symptoms in patients with FD.

METHODS

The validated National Institutes of Health Patient-Reported Outcomes Measurement Information System (PROMIS) survey questionnaire, together with additional FD-specific questions, were distributed to 202 living patients with genetically confirmed FD who had been identified from the New York University FD Patient Registry or, when relevant, to their respective caretaker. As a comparison group, we used a general US adult population for whom PROMIS scores were available (N = 71,812).

RESULTS

Of the 202 questionnaires distributed, 77 (38%) were returned, of which 53% were completed by the patient. Median age of the respondents was 25 years, and 44% were male. Gastrostomy tube was the sole nutrition route for 25% of the patients, while 53% were reliant on the gastrostomy tube only for liquid intake. The prevalence of gastrointestinal symptoms was significantly higher in each of the eight domains of PROMIS in patients with FD than in the controls. Gastrointestinal symptoms as measured by raw scores on the PROMIS scale were significantly less severe in the FD patient group than in the control population in all domains with the exception of the abdominal pain domain. The surveys completed by caregivers reported the same burden of symptoms as those completed only by patients.

CONCLUSION

Gastrointestinal symptoms affect nearly all patients with FD. Gastrointestinal symptoms are more prevalent in adult patients with FD than in the average US adult population but are less severe in the former.

Clinicopathology and Diagnosis Delay in a 40-Year-Old with Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE)

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is an autosomal recessive and fatal multisystem metabolic disorder. It presents with wide-ranging gastrointestinal and neurologic symptoms. It is caused by a mutation in the TYMP gene which impairs thymidine phosphorylase (TP) activity, therefore leading to the accumulation of thymidine and deoxyuridine in plasma and tissues. Thus, MNGIE can be diagnosed by findings of high levels of thymidine and deoxyuridine. Herein, we present the case of a 40-year-old male who presented with diarrhea, vomiting, and abdominal pain, severe weight loss, neurologic deficits, and distal motor weakness progressing over a period of 13 years. The combination of this broad clinical picture along with results of magnetic resonance imaging, electromyography, colonic biopsies, genetic testing, and elevated plasma and tissue thymidine and deoxyuridine levels confirmed the diagnosis of MNGIE. TYMP gene mutation impairs TP function. TP mutations in the nuclear DNA lead to mitochondrial DNA deletions causing mitochondrial failure and ultimately cell death. Treatment modalities are targeting the restoration of TP activity or aiming to decrease the high levels of thymidine and pyrimide. However, diagnosing this disease is still a challenge and often overdue. This patient's 13-year delay in diagnosis shows the importance of a complete neurological exam and muscle strength testing in patients with gastrointestinal symptoms. The diagnosis of MNGIE requires interdepartmental collaborative work for diagnosis delay prevention and for optimal patient care.

Recommendations for the reopening and activity resumption of the neurogastroenterology units in the face of the COVID-19 pandemic. Position of the Sociedad Latinoamericana de Neurogastroenterología

The COVID-19 pandemic has forced the establishment of preventive measures against contagion during the performance of diagnostic and therapeutic tests in gastroenterology. Digestive tract motility tests involve an intermediate and elevated risk for the transmission of COVID-19 infection. Given their elective or non-urgent indication in the majority of cases, we recommend postponing those tests until significant control of the infection rate in each Latin American country has been achieved during the pandemic. When the health authorities allow the return to normality, and in the absence of an effective treatment for or preventive vaccine against COVID-19 infection, we recommend a strict protocol for classifying patients according to their infectious-contagious status through the appropriate use of tests for the detection of the virus and the immune response to it, and the following of protective measures by the healthcare personnel to prevent contagion during the performance of a gastrointestinal motility test.

Engineering a second brain in a dish

The utilization of human pluripotent stem cells holds great promise in elucidating principles of developmental biology and applications in personalized and regenerative medicine. Breakthroughs from the last decade have allowed the scientific community to better understand and successfully manipulate human pluripotent stem cells using distinct differentiation strategies into a variety of target tissues. This manipulation relies solely on our understanding of developmental processes occurring in model organisms. The in vitro translation of our developmental knowledge upon stem cells provides a new means to generate specific tissue to understand developmental and disease mechanisms, as well as physiological processes. The generation of an integrated human intestinal tissue is one such example. In this review, we highlight the biological motivation behind the generation of human intestinal organoids. We further describe the integration of an enteric nervous system within the organoid to generate a functional intestine. Forthcoming strategies to add additional complexities to the intestinal tissue so as to better understand how our "second brain" functions within the gut are also discussed. The organoid system offers a promising avenue to understand how the enteric nervous system works and patterns the human intestine during both physiology and disease.

Effect of transcutaneous vagus nerve stimulation on muscle activity in the gastrointestinal tract (transVaGa): a prospective clinical trial

PURPOSE

Postoperative ileus (POI) is a common complication after abdominal surgery. Invasive stimulation of the cervical vagus nerve is known to reduce inflammatory response and ameliorated POI after surgery in a mouse model. However, the transcutaneous vagus nerve stimulation (tVNS) is a possible non-invasive approach. In this clinical study, we aimed to investigate the effect of tVNS on the activation of the stomach muscle in humans.

METHODS

Patients requiring open laparotomy were screened for this prospective proof of concept clinical study. After open laparotomy, muscle activity of the stomach was measured by a free running electromyography (EMG) before and during tVNS on the ear. Frequency and amplitude of compound gastric action potentials were the electrophysiological parameters we assessed to reveal the changes in electro motor gastric activity. Gastrin levels as a surrogate marker for vagus nerve activation was analyzed before, 1 and 3 h after tVNS.

RESULTS

Fourteen patients were included, no severe adverse events and no medical device related adverse events occurred. tVNS led to significant reduction of action potential frequency and significant elevation of action potential amplitude in the stomach compared to control. Gastrin levels were significantly elevated 3 h after tVNS compared to levels before tVNS.

CONCLUSION

Application of tVNS is a safe and feasible procedure during surgical intervention. Our results provide evidence that tVNS activates efferent visceral vagal fibers. Therefore, this low risk and easy to perform method could be useful to prevent postoperative ileus.

CLINICAL TRIAL REGISTER NUMBER

DRKS00013340.

Computational motility models of neurogastroenterology and neuromodulation

The success of neuromodulation therapies, particularly in the brain, spinal cord, and peripheral nerves, has been greatly aided by computational, biophysical models. However, treating gastrointestinal disorders with electrical stimulation has been much less explored, partly because the mode of action of such treatments is unclear, and selection of stimulation parameters is often empirical. Progress in gut neuromodulation is limited by the comparative lack of biophysical models capable of simulating neuromodulation of gastrointestinal function. Here, we review the recently developed biophysical models of electrically-active cells in the gastrointestinal system that contribute to motility. Biophysical models are replacing phenomenologically-defined models due to advancements in electrophysiological characterization of key players in the gut: enteric neurons, smooth muscle fibers, and interstitial cells of Cajal. In this review, we explore existing biophysically-defined cellular and network models that contribute to gastrointestinal motility. We focus on recent models that are laying the groundwork for modeling electrical stimulation of the gastrointestinal system. Developing models of gut neuromodulation will improve our mechanistic understanding of these treatments, leading to better parameterization, selectivity, and efficacy of neuromodulation to treat gastrointestinal disorders. Such models may have direct clinical translation to current neuromodulation therapies, such as sacral nerve stimulation.

Recurrent episodes of esophageal candidiasis without dysphagia post-Guillain-Barré syndrome: an unusual presentation of achalasia

Here, we present a case of a 50-year-old male with a history of a Guillain-Barré-syndrome, who was referred to our clinic with recurrent esophageal candidiasis and long-standing intermittent retrosternal cramps for further evaluation. Other symptoms such as dysphagia, regurgitations and weight loss were denied, and prior repeated endoscopy was otherwise unremarkable. Using high resolution impedance manometry, we could demonstrate a panesophageal pressure increase on water swallows and complete aperistalsis of the tubular esophagus, indicating achalasia type II. However, due to the patient's extraordinary body height and resulting length of the esophagus, endoluminal functional lumen imaging probe analysis supplementary to high resolution impedance manometry needed to be used to assess distensibility of the esophagogastral junction and to secure the diagnosis of achalasia before appropriately treating the patient with pneumatic dilation.

Autoimmune gastrointestinal dysmotility due to small cell lung cancer

The diagnosis of autoimmune gastrointestinal dysmotility requires a high level of clinical suspicion when standard work-up is unrevealing. We report the case of a 56-year-old male patient with history of tobacco use and a subacute presentation of weight loss, vomiting and cerebellar ataxia. The discovery of paraneoplastic type 1 antineuronal nuclear antibodies and neuronal acetylcholine receptor antibodies led to further directed imaging and diagnostic studies in spite of prior negative chest imaging. Bronchoscopy with endobronchial ultrasound was used to confirm a diagnosis of small cell lung cancer and paraneoplastic syndrome as the cause of the presenting upper gastrointestinal symptoms.

Unremitting watery diarrhoea in early childhood period

Chronic watery diarrhoea can be a presentation of gastrointestinal disease itself or a less-evident systemic disease. A 17-month-old boy presented with intractable diarrhoea, failure to gain weight, refractory tachycardia and severe hypertension. The ability to recognise and make a quick diagnosis of secretory type of diarrhoea dictated the outcome of patients with this ailment. Catecholamine hypersecretion was considered with the additional clues of refractory tachycardia and hypertension, a well-recognised phenomenon of neuroblastic tumours. A neuroblastic tumour can lead to vasoactive intestinal peptide (VIP) overexpression, which may result in secretory diarrhoea. In this situation, measurements of plasma VIP enabled crucial diagnosis. Imaging studies were used to identify and localise a neuroblastic tumour. Subsequent removal of the tumour was curative and led to the resolution of the symptoms.

Functional Gastrointestinal Disorders: History, Pathophysiology, Clinical Features and Rome IV

Functional gastrointestinal disorders (FGIDs), the most common diagnoses in gastroenterology are recognized by morphological and physiological abnormalities that often occur in combination including motility disturbance, visceral hypersensitivity, altered mucosal and immune function, altered gut microbiota and altered central nervous system processing. Research on these gut-brain interaction disorders is based on using specific diagnostic criteria. The Rome Foundation has played a pivotal role in creating diagnostic criteria thus operationalizing the dissemination of new knowledge in the field of FGIDs. Rome IV is a compendium of the knowledge accumulated since Rome III was published 10 years ago. It improves upon Rome III by: 1) updating the basic and clinical literature, 2) offering new information on gut microenvironment, gut-brain interactions, pharmacogenomics, biopsychosocial, gender and cross cultural understandings of FGIDs, 3) reduces the use of imprecise and occassionally stigmatizing terms when possible, 4) uses updated diagnostic algorithms, 5) incorporates information on the patient illness experience, and physiological subgroups or biomarkers that might lead to more targeted treatment. This introductory article sets the stage for the remaining 17 articles that follow and offers an historical overview of the FGIDs field, differentiates FGIDs from motility and structural disorders, discusses the changes from Rome III, reviews the Rome committee process, provides a biopsychosocial pathophysiological conceptualization of FGIDs, and offers an approach to patient care.

Comparing the Areas of Interest in the Field of Functional Gastrointestinal Disorder and Neurogastroenterology and Motility Between the East and the West

There is a paucity of studies that compare the differences in published articles submitted from the East and the West in the area of neurogastroenterology and motility (NM). To compare the article topics from the East and the West which have been published, 5 Western (Gastroenterology, Gut, American Journal of Gastroenterology, American Journal of Physiology-Gastrointestinal and Liver Physiology, and Neurogastroenterology and Motility) and 3 Eastern gastrointestinal journals (Journal of Gastroenterology, Journal of Gastroenterology and Hepatology, and Journal of Neurogastroenterology and Motility) were selected based on the impact factor. Published papers were classified into 12 categories and 60 subcategories. The titles and abstracts of review articles, original articles, and meta-analyses from these journals were reviewed for the last 2 years (2013–2014). In case of Journal of Neurogastroenterology and Motility which is published quarterly, this search was performed for 5 years (2010–2014). Of the total 2656 reviewed articles, 842 (260 from the East and 582 from the West) were classified into the category of NM. The most frequently published papers from the Western researchers were categorized as brain-gut interaction, visceral hypersensitivity, and irritable bowel syndrome, whereas those from the Eastern researchers were categorized as gastroesophageal reflux disease, functional dyspepsia, and irritable bowel syndrome. This difference between the East and the West is not just due to the journal itself, but it also depends on the author’s affiliation and their ability to perform high quality research in the area of the NM. These data provide evidence for the research trend and give valuable information to the researchers for determining subjects for the study and for selecting proper journals for publishing their studies.

Pharmacological reduction of mucosal but not neuronal serotonin opposes inflammation in mouse intestine

OBJECTIVE

Enterochromaffin cell-derived serotonin (5-HT) promotes intestinal inflammation. We tested hypotheses that peripheral tryptophan hydroxylase (TPH) inhibitors, administered orally, block 5-HT biosynthesis and deplete 5-HT from enterochromaffin cells sufficiently to ameliorate intestinal inflammation; moreover, peripheral TPH inhibitors fail to enter the murine enteric nervous system (ENS) or central nervous systems and thus do not affect constitutive gastrointestinal motility.

DESIGN

Two peripheral TPH inhibitors, LP-920540 and telotristat etiprate (LX1032; LX1606) were given orally to mice. Effects were measured on 5-HT levels in the gut, blood and brain, 5-HT immunoreactivity in the ENS, gastrointestinal motility and severity of trinitrobenzene sulfonic acid (TNBS)-induced colitis. Quantitation of clinical scores, histological damage and intestinal expression of inflammation-associated cytokines and chemokines with focused microarrays and real-time reverse transcriptase PCR were employed to evaluate the severity of intestinal inflammation.

RESULTS

LP-920540 and LX1032 reduced 5-HT significantly in the gut and blood but not in the brain. Neither LP-920540 nor LX1032 decreased 5-HT immunoreactive neurons or fibres in the myenteric plexus and neither altered total gastrointestinal transit time, colonic motility or gastric emptying in mice. In contrast, oral LP-920540 and LX1032 reduced the severity of TNBS-induced colitis; the expression of 24% of 84 genes encoding inflammation-related cytokines and chemokines was lowered at least fourfold and the reduced expression of 17% was statistically significant.

CONCLUSIONS

Observations suggest that that peripheral TPH inhibitors uncouple the positive linkage of enterochromaffin cell-derived 5-HT to intestinal inflammation. Because peripheral TPH inhibitors evidently do not enter the murine ENS, they lack deleterious effects on constitutive intestinal motility in mice.

Cellular and molecular basis of chronic constipation: Taking the functional/idiopathic label out

In recent years, the improvement of technology and the increase in knowledge have shifted several strongly held paradigms. This is particularly true in gastroenterology, and specifically in the field of the so-called “functional” or “idiopathic” disease, where conditions thought for decades to be based mainly on alterations of visceral perception or aberrant psychosomatic mechanisms have, in fact, be reconducted to an organic basis (or, at the very least, have shown one or more demonstrable abnormalities). This is particularly true, for instance, for irritable bowel syndrome, the prototype entity of “functional” gastrointestinal disorders, where low-grade inflammation of both mucosa and myenteric plexus has been repeatedly demonstrated. Thus, researchers have also investigated other functional/idiopathic gastrointestinal disorders, and found that some organic ground is present, such as abnormal neurotransmission and myenteric plexitis in esophageal achalasia and mucosal immune activation and mild eosinophilia in functional dyspepsia. Here we show evidence, based on our own and other authors’ work, that chronic constipation has several abnormalities reconductable to alterations in the enteric nervous system, abnormalities mainly characterized by a constant decrease of enteric glial cells and interstitial cells of Cajal (and, sometimes, of enteric neurons). Thus, we feel that (at least some forms of) chronic constipation should no more be considered as a functional/idiopathic gastrointestinal disorder, but instead as a true enteric neuropathic abnormality.

Neuropathophysiology of functional gastrointestinal disorders

The investigative evidence and emerging concepts in neurogastroenterology implicate dysfunctions at the levels of the enteric and central nervous systems as underlying causes of the prominent symptoms of many of the functional gastrointestinal disorders. Neurogastroenterological research aims for improved understanding of the physiology and pathophysiology of the digestive subsystems from which the arrays of functional symptoms emerge. The key subsystems for defecation-related symptoms and visceral hyper-sensitivity are the intestinal secretory glands, the musculature and the nervous system that controls and integrates their activity. Abdominal pain and discomfort arising from these systems adds the dimension of sensory neurophysiology. This review details current concepts for the underlying pathophysiology in terms of the physiology of intestinal secretion, motility, nervous control, sensing function, immuno-neural communication and the brain-gut axis.