Cerebellar degeneration and hearing loss in a patient with idiopathic myenteric ganglionitis

Chronic intestinal pseudo-obstruction in adults: A practical guide to identify patient subgroups that are suitable for more specific treatments

Chronic intestinal pseudo-obstruction is a rare and heterogeneous syndrome characterized by recurrent symptoms of intestinal obstruction with radiological features of dilated small or large intestine with air/fluid levels in the absence of any mechanical occlusive lesion. Several diseases may be associated with chronic intestinal pseudo-obstruction and in these cases, the prognosis and treatment are related to the underlying disease. Also, in its "primary or idiopathic" form, two subgroups of patients should be determined as they require a more specific therapeutic approach: patients whose chronic intestinal pseudo-obstruction is due to sporadic autoimmune/inflammatory mechanisms and patients whose neuromuscular changes are genetically determined. In a context of a widely heterogeneous adult population presenting chronic intestinal pseudo-obstruction, this review aims to summarize a practical diagnostic workup for identifying definite subgroups of patients who might benefit from more specific treatments, based on the etiology of their underlying condition.

Review of the indications, methods, and clinical utility of anorectal manometry and the rectal balloon expulsion test

BACKGROUND

Anorectal manometry (ARM) comprehensively assesses anorectal sensorimotor functions.

PURPOSE

This review examines the indications, techniques, interpretation, strengths, and weaknesses of high-resolution ARM (HR-ARM), 3-dimensional high-resolution anorectal manometry (3D-HR-ARM), and portable ARM, and other assessments (i.e., rectal sensation and rectal balloon expulsion test) that are performed alongside manometry. It is based on a literature search of articles related to ARM in adults. HR-ARM and 3D-HR-ARM are useful for diagnosing defecatory disorders (DD), to identify anorectal sensorimotor dysfunction and guide management in patients with fecal incontinence (FI), constipation, megacolon, and megarectum; and to screen for anorectal structural (e.g., rectal intussusception) abnormalities. The rectal balloon expulsion test is a useful, low-cost, radiation-free, outpatient assessment tool for impaired evacuation that is performed and interpreted in conjunction with ARM. The anorectal function tests should be interpreted with reference to age- and sex-matched normal values, clinical features, and results of other tests. A larger database of technique-specific normal values and newer paradigms of analyzing anorectal pressure profiles will increase the precision and diagnostic utility of HR-ARM for identifying abnormal mechanisms of defecation and continence.

Paraneoplastic vs. non-paraneoplastic anti-Hu associated dysmotility: a case series and literature review

OBJECTIVES

This work aimed to report the demographic and clinical characteristics of two new cases with non-paraneoplastic anti-Hu-associated gut motility impairment, and perform a thorough revision covering anti-Hu-associated paraneoplastic (PGID) and non-paraneoplastic (nPGID) gastrointestinal dysmotility.

BACKGROUND

Several case series have clearly established a relationship between certain type of cancers, the development of circulating anti-Hu antibodies, and the concomitant usually severe gastrointestinal dysmotility; in contrast, a few studies focused on anti-Hu-associated nPGID.

METHODS

We searched for studies regarding anti-Hu-associated gastrointestinal manifestations and extracted data concerning clinical characteristics of patients, including specific demographic, oncological, neurological, gastrointestinal, histological, and treatment response features.

RESULTS

Forty-nine articles with a total of 59 cases of anti-Hu-associated gastrointestinal dysmotility were analyzed. The patients' age at symptom onset significantly differed between PGID and nPGID (median 61 vs 31 years, p < 0.001). Most cancers (95%) in PGID were detected within 24 months from the beginning of gastrointestinal symptoms. The impairment of gastrointestinal motility was generalized (i.e., involving the whole gut) in 59.3% of patients, with no significant differences between PGID vs nPGID group. nPGID patients showed a better response to immunomodulatory/immunosuppressive treatment and a longer life expectancy.

CONCLUSIONS

Anti-Hu-associated gastrointestinal dysmotility covers a wide clinical spectrum. Patients with otherwise unexplained gastrointestinal dysmotility, especially when associated with other neurological symptoms, should be tested for anti-Hu antibodies regardless age of onset and disease duration. Compared to PGID, nPGID occurs in younger patients with a long duration of disease.

Case Report: Anti-NMDA Receptor Encephalitis With Bilateral Hearing Loss as the Initial Symptom

Introduction: Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an autoimmune disease associated with the NMDA receptor. This paper describes a patient who presented with bilateral hearing loss as the initial symptom of anti-NMDAR encephalitis.

Case Report: We describe a 31-year-old young female with anti-NMDAR encephalitis who presented with bilateral severe hearing loss after brief loss of consciousness and then accompanied by other symptoms, such as generalized tonic–clonic seizures, manic episodes, excessive salivation, severe cognitive impairment, and complex non-convulsive status epilepticus. Great improvement was achieved by a combined treatment of steroid, IVIG, and plasmapheresis, especially after surgical removal of the ovarian teratoma. When she was discharged on hospital day 43, her hearing loss obtained a significant improvement.

Conclusion: This case study and literature review investigated the impairment of hearing loss and its subsequent treatment in patients with anti-NMDAR encephalitis.

Idiopathic myenteric ganglionitis as a cause of death in a young male patient with sudden abdominal pain: an autopsy case report

BACKGROUND

Myenteric ganglionitis is a disorder that causes intestinal motor dysfunction. It may be caused due to neoplastic, central nervous system, or systemic infectious disorders. However, some cases are considered to be idiopathic in origin.

CASE PRESENTATION

A 33-year-old man was admitted to the hospital with sudden severe abdominal pain accompanied by watery diarrhea. Computed tomography imaging revealed edema of the entire small intestinal wall without ischemic changes. Detailed examination could not be performed for identifying the cause of abdominal pain because of the patient's worsened general condition, and he died 7 days after onset. The autopsy results confirmed the cause of the patient's severe abdominal pain as an idiopathic myenteric ganglionitis.

CONCLUSION

Some patients with idiopathic myenteric ganglionitis might die without a definitive diagnosis during their lifetime because of the rarity of this disease. When encountering severe intestinal motility abnormalities of unknown cause, physicians should consider idiopathic myenteric ganglionitis when choosing therapy.

Fatal enteric plexus neuropathy after one dose of ipilimumab plus nivolumab: a case report

Background

Immune checkpoint inhibitors (ICIs) are the treatment of choice for several cancers and can be associated with remarkable clinical benefit, but can also cause serious immune-related adverse events (irAEs). Management of rare and severe irAEs is challenged by an incomplete knowledge of their natural history and pathogenetic mechanisms. We report a case of fatal acute-onset gastro-intestinal (GI) hypomotility from myenteric plexus neuropathy following a single dose of ipilimumab plus nivolumab given for treatment of Merkel cell carcinoma (MCC).

Case presentation

A 66-year-old man with recurrent metastatic MCC involving several organs (liver, bones and disseminated retroperitoneal lymphadenopathy) developed profound pharyngeal dysphagia and ileus that started 7 days after receiving a single administration of combination immune checkpoint blockade consisting of nivolumab (3 mg/kg) and low-dose ipilimumab (1 mg/kg). A swallowing study showed oropharyngeal dysfunction and aspiration. Imaging studies were consistent with diffuse intestinal paresis. An extensive work-up did not reveal obvious causes of these symptoms, and enteric plexopathy was suspected. Empiric immune suppressive therapy was initiated urgently. Despite an escalating immunosuppressive regimen that included high dose steroids, tacrolimus and therapeutic plasma exchange, no improvement in GI motility was seen and the patient suffered repeated episodes of aspiration. Seven weeks after the onset of GI hypomotility, the patient succumbed to sepsis from intestinal perforations. At autopsy, histologic specimens obtained from the entire GI tract (pharynx to rectum) showed near complete loss of ganglion cells within the myenteric and submucosal plexuses. An associated inflammatory infiltrate was not seen, suggesting a ‘burned out’ phase of illness. C4d complement deposition was found at the ganglionic sites, suggesting antibody-mediated pathogenesis. Remarkably, at sites of previously suspected Merkel cell metastases, no residual viable Merkel cell carcinoma was identified.

Conclusions

GI-tract paresis due to myenteric neuritis is a rarely reported toxicity of ICIs. Because the window of reversibility is likely to be very brief, quick and decisive interventions are warranted. Subtle functional and anatomic perturbations of the myenteric nervous system from the use of ICIs may be more prevalent than realized and should be suspected and addressed in both clinical and investigational settings.

Oesophageal motor function in chronic intestinal idiopathic pseudo-obstruction: A study with high-resolution manometry

BACKGROUND

Chronic intestinal idiopathic pseudo-obstruction (idiopathic CIPO) is a rare heterogeneous condition for which the different phenotypes are difficult to be established. Oesophageal motility has shown to be impaired in patients with idiopathic CIPO at traditional manometry, whereas no studies have assessed it by high resolution manometry (HRM).

AIMS

To evaluate oesophageal motility by HRM in patients with idiopathic CIPO.

METHODS

14 patients with idiopathic CIPO underwent oesophageal HRM. Multiple rapid swallows (MRS) were performed in order to evaluate contraction reserve. The Chicago Classification 3.0 was used to classify the oesophageal motility disorders.

RESULTS

One idiopathic CIPO patient had type-II achalasia, one aperistalsis and 12 had minor disorder of peristalsis (11 ineffective oesophageal motility and one fragmented peristalsis). These minor disorders were not significantly different from those of 50 other consecutive patients who underwent HRM for dysphagia or GERD and received the diagnosis of ineffective oesophageal motility. Three of the 12 idiopathic CIPO patients with minor disorder of peristalsis had no contraction reserve after MRS.

CONCLUSIONS

HRM is able to identify different grades of oesophageal motor impairment in patients with idiopathic CIPO. Presence of major oesophageal dismotility or absent contraction reserve suggest a more severe and widespread motor disorder.

High-resolution anorectal manometry: An expensive hobby or worth every penny?

Introduced approximately 10 years ago, high-resolution manometry catheters have fostered interest in anorectal manometry. This review, which accompanies two articles in this issue of Neurogastroenterology and Motility, reviews the methods, clinical indications, utility, and pitfalls of anorectal manometry and revisits the American Gastroenterological Association (AGA) Medical Position Statement on Anorectal Testing Techniques, which was last published in 1999. High-resolution manometry provides a refined assessment of the anorectal pressure profile, obviates the need for station pull-through maneuvers, and minimizes movement artifacts. In selected cases, this refined assessment may be useful for identifying structural abnormalities or anal weakness. However, many manometry patterns that were previously regarded as abnormal are also observed in a majority of healthy patients, which substantially limits the utility of manometry for identifying defecatory disorders. It is our impression that most conclusions of the AGA medical position statement from 1999 remain valid today. High-resolution techniques have not substantially affected the number of publications on or management of anorectal disorders. The ongoing efforts of an international working group to standardize techniques for anorectal manometry are welcome. Although high-resolution manometry is more than an expensive hobby, improvements in catheter design and further research to rigorously define and evaluate these techniques are necessary to determine if they are worth every penny.

Expression pattern and localization of alpha-synuclein in the human enteric nervous system

BACKGROUND

Alpha-synuclein (α-syn) is abundantly expressed in the central nervous system and involved in the regulation of neurotransmission. Insoluble fibrils of phosphorylated α-synuclein (p-α-syn) have been implicated in several neurodegenerative diseases (e.g. Parkinson's disease, Alzheimer's disease). The aim of the study was to determine the gene expression pattern and localization of α-syn/p-α-syn in the human enteric nervous system (ENS).

METHODS

Human colonic specimens (n=13, 15-83 years) were processed for α-syn and p-α-syn immunohistochemistry. Colocalization of α-syn was assessed by dual-labeling with pan-neuronal markers (PGP 9.5, HuC/D). For qPCR studies, tissue was obtained from full-thickness sections, tunica muscularis, submucosa, mucosa, and laser-microdissected (LMD) enteric ganglia.

RESULTS

Highest α-syn levels were detectable within the tunica muscularis and submucosa. Ganglia isolated by LMD showed high expression of α-syn mRNA. All myenteric and submucosal ganglia and nerve fibers were immunoreactive for α-syn. Dual-labeling revealed colocalization of α-syn with both pan-neuronal markers. p-α-syn immunoreactivity was consistently observed in specimens from adults with increasing age.

CONCLUSIONS

α-syn is abundantly expressed in all nerve plexus of the human ENS including both neuronal somata and processes. The presence of p-α-syn within the ENS is a regular finding in adults with increasing age and may not be regarded as pathological correlate. The data provide a basis to unravel the functions of α-syn and to evaluate altered α-syn in enteric neuropathies and α-synucleinopathies of the CNS with gastrointestinal manifestations.

Colonic biopsies to assess the neuropathology of Parkinson's disease and its relationship with symptoms

Background

The presence of Lewy bodies and Lewy neurites (LN) has been demonstrated in the enteric nervous system (ENS) of Parkinson's disease (PD) patients. The aims of the present research were to use routine colonoscopy biopsies (1) to analyze, in depth, enteric pathology throughout the colonic submucosal plexus (SMP), and (2) to correlate the pathological burden with neurological and gastrointestinal (GI) symptoms.

Methodology/Principal Findings

A total of 10 control and 29 PD patients divided into 3 groups according to disease duration were included. PD and GI symptoms were assessed using the Unified Parkinson's Disease Rating Scale part III and the Rome III questionnaire, respectively. Four biopsies were taken from the ascending and descending colon during the course of a total colonoscopy. Immunohistochemical analysis was performed using antibodies against phosphorylated alpha-synuclein, neurofilaments NF 220 kDa (NF) and tyrosine hydroxylase (TH). The density of LN, labeled by anti-phosphorylated alpha-synuclein antibodies, was evaluated using a quantitative rating score. Lewy pathology was apparent in the colonic biopsies from 21 patients and in none of the controls. A decreased number of NF-immunoreactive neurons per ganglion was observed in the SMP of PD patients compared to controls. The amount of LN in the ENS was inversely correlated with neuronal count and positively correlated with levodopa-unresponsive features and constipation.

Conclusion/Significance

Analysis of the ENS by routine colonoscopy biopsies is a useful tool for pre-mortem neuropathological diagnosis of PD, and also provides insight into the progression of motor and non-motor symptoms.

Interstitial cells of Cajal in the gut - A gastroenterologist’s point of view

Alterations of normal function of interstitial cells of Cajal (ICC) are reported in many intestinal disorders. Diagnosis of their involvement is rare (infrequent), but necessary to propose a specific treatment. This article reviews the place of ICC in the pathogenesis of achalasia, gastroesophageal reflux disease, infantile hypertrophic pyloric stenosis, chronic intestinal pseudo-obstruction and slow transit constipation. Moreover we discuss the role of the Cajal cells in the development of stromal tumors of the gastrointestinal tract.

Enteric nervous system

PURPOSE OF REVIEW

Our aim was to provide a synopsis of how the field of enteric neurobiology has advanced during the past year.

RECENT FINDINGS

With such a large number of studies to choose from and given our emphasis in last year's issue on developmental aspects of the enteric nervous system, we have focused on several key themes reflecting the current interest in the way the enteric nervous system is altered in disease.

SUMMARY

The new basic science information gathered during the past year provides insight into pathophysiological processes and will pave the way for improved understanding of both organic and 'functional' gastrointestinal disorders.