Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014848 (achalasia)
 2,804 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inflammatory neuropathy of the enteric nervous system is emerging as an important topic in the field of neurogastroenterology. Enteric ganglionitis can be either primary or secondary to a wide array of diseases (i.e., paraneoplastic, infectious, and neurological disorders) and is characterized by a dense infiltrate of inflammatory/immune cells mainly confined to the neural microenvironment. The clinical picture reflects the involved segment of the gastrointestinal tract (achalasia, gastroparesis, pseudo-obstruction, and megacolon). In these settings, symptoms may develop either acutely (frequently after a flulike episode in otherwise previously healthy individuals) or more slowly (e.g., in paraneoplastic syndromes). The inflammatory/immune response in enteric ganglionitis leads to neuronal dysfunction and degeneration over time and sometimes results in a complete loss of enteric neurons. The diagnosis of enteric ganglionitis is supported by detection of circulating antineuronal antibodies against select molecular targets, including Hu and Yo proteins, neurotransmitter receptors, and ion channels. Potential mechanisms involved in neuronal dysfunction include viral antigen expression in the enteric neural environment, molecular mimicry (onconeural antigens), and the role exerted by cellular and humoral autoimmunity. A short course of steroid or other immunosuppressive therapy has been shown to be helpful in the treatment of these conditions. This feature reinforces the concept of a cause/effect relationship of the immune-mediated insult damaging the enteric innervation. An increased awareness of the clinical features and the immunologic and neurodegenerative mechanisms of these forms of peripheral neuropathy is important to correctly diagnose this problem during the early stages of the disease process and to provide appropriate immunosuppressive therapies.
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PMID:Inflammatory neuropathies of the enteric nervous system. 1518 82

The aim of this study is to review current understanding of the molecular and morphological pathology of the enteric neuropathies affecting motor function of the human gastrointestinal tract and to evaluate the described pathological entities in the literature to assess whether a new nosology may be proposed. The authors used PUBMED and MEDLINE searches to explore the literature pertinent to the molecular events and pathology of gastrointestinal motility disorders including achalasia, gastroparesis, intestinal pseudo-obstruction, colonic inertia and megacolon in order to characterize the disorders attributable to enteric gut neuropathies. This scholarly review has shown that the pathological features are not readily associated with clinical features, making it difficult for a patient to be classified into any specific category. Individual patients may manifest more than one of the morphological and molecular abnormalities that include: aganglionosis, neuronal intranuclear inclusions and apoptosis, neural degeneration, intestinal neuronal dysplasia, neuronal hyperplasia and ganglioneuromas, mitochondrial dysfunction (syndromic and non-syndromic), inflammatory neuropathies (caused by cellular or humoral immune mechanisms), neurotransmitter diseases and interstitial cell pathology. The pathology of enteric neuropathies requires further study before an effective nosology can be proposed. Carefully studied individual cases and small series provide the basic framework for standardizing the collection and histological evaluation of tissue obtained from such patients. Combined clinical and histopathological studies may facilitate the translation of basic science to the clinical management of patients with enteric neuropathies.
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PMID:Human enteric neuropathies: morphology and molecular pathology. 1550 May 8

Tumor-associated gastroparesis, though reported in association with various malignancies, is rare in patients with cholangiocarcinoma. We report a 55-year-old woman who presented with dysphagia and recurrent vomiting. Esophagogastroduodenoscopy revealed dilated stomach and excess residue without organic obstruction. 99mTc sulfur colloid solid gastric emptying study, radio-opaque marker gut transit study, and esophageal manometry showed features suggestive of gastroparesis and achalasia cardia; electrogastrography revealed bradygastria. Cholangiocarcinoma was detected on CT scan performed after the patient developed jaundice two months later. The lesion was deemed surgically unresectable. She died four months later.
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PMID:Cholangiocarcinoma presenting with severe gastroparesis and pseudoachalasia. 1620 7

Botulinum toxin has gained widespread acceptance as a treatment option for various spastic gastrointestinal disorders such as achalasia, gastroparesis, sphincter of Oddi dysfunction, chronic anal fissures, and pelvic floor dyssnergia, despite the lack of strong evidence supporting its use in many of these diseases. This review summarizes the trials investigating the use of BoNT since it was first utilized as a treatment in achalasia. BoNT has proven to be safe, but long-term efficacy in many disorders has not been observed, primarily due to is relatively short duration of action. BoNT may be most useful in confirming a diagnosis which can lead to a more definitive treatment modality. Furthermore, its safety profile allows it to be a useful alternative in patients who are at high risk for invasive procedures.
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PMID:Botulinum toxin for gastrointestinal disorders: therapy and mechanisms. 1678 13

Gastrointestinal motility disorders encompass a wide array of signs and symptoms that can occur anywhere throughout the luminal gastrointestinal tract. Motility disorders are often chronic in nature and dramatically affect patients' quality of life. These prevalent disorders cause a tremendous impact both to the individual patient and to society as a whole. Significant progress has been made over the last 5 years in understanding the etiology and pathophysiology of gastrointestinal motility disorders. This clinical update will focus on seven of the most common gastrointestinal motility disorders (achalasia, non-achalasia esophageal motility disorders, dyspepsia, gastroparesis, chronic intestinal pseudo-obstruction, irritable bowel syndrome, and chronic constipation) with an emphasis on current treatment options and new therapeutic modalities.
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PMID:Gastrointestinal motility disorders: an update. 1684 50

Patients who are unresponsive to 4-8 weeks' treatment with PPIs twice daily might have so-called refractory GERD. The first investigation these patients should undergo is upper endoscopy to exclude a diagnosis of peptic ulcer disease or cancer and identify the presence of esophagitis. The presence of esophagitis in these patients is suggestive of a pill-induced injury, an autoimmune skin disease involving the esophagus, eosinophilic esophagitis or, less likely, a hypersecretory syndrome or a genotype that confers altered metabolism of PPIs. Refractory reflux syndromes associated with normal endoscopy findings are more problematic to diagnose and further testing may be required, including prolonged 48 h pH testing, impedance measurements (for nonacid reflux), esophageal manometry and gastric function tests. For patients with refractory GERD who do not have esophagitis, possible etiologies include nocturnal gastric acid breakthrough, nonacid GER, missed GER or other diseases such as achalasia, gastroparesis or functional heartburn.
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PMID:How to manage refractory GERD. 1804 75

Refractory gastro-oesophageal reflux disease (GORD) is described when reflux symptoms have not responded to 4-8 weeks of proton pump inhibitor therapy and occurs in a heterogeneous mixture of patients. The causes of refractory GORD include inadequate acid suppression, non-acid gastro-oesophageal reflux, and non-reflux causes of GORD symptoms including achalasia, gastroparesis and functional heartburn. Upper gastrointestinal tract endoscopy should initially be performed to identify the presence of oesophagitis, and exclude other diagnoses including eosinophilic oesophagitis and peptic ulcer disease. Patients with refractory symptoms but with a normal upper endoscopy are more difficult to diagnose and may require ambulatory pH monitoring, impedance testing, oesophageal motility tests and gastric emptying scans. The primary goal of treatment is symptom reduction and eventual elimination, which can be achieved with proper identification of the underlying cause of the symptoms.
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PMID:Refractory gastro-oesophageal reflux disease: diagnosis and management. 1974 9

We review the current clinical evaluation and management of the most common esophageal and gastrointestinal motility disorders in children based on the literature and our experience in a pediatric motility center in the United States. The disorders discussed include esophageal achalasia, pre- and post-fundoplication motility disorders, gastroparesis, motility disorders occurring after repair of congenital atresias, motility disorders associated with gastroschisis, chronic intestinal pseudo-obstruction, motility after intestinal transplantation, motility disorders after colonic resection for Hirschsprung's disease, chronic functional constipation, and motility disorders associated with imperforate anus.
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PMID:Clinical management of motility disorders in children. 1978 4

Nitric oxide (NO) is a functionally important neurotransmitter signaling molecule generated by mammalian and bacterial nitric oxide synthases (NOS), and by chemical conversion of dietary nitrite in the gastrointestinal (GI) tract. Neuronal NOS (nNOS) is the most abundant isoenzyme in the enteric nervous system, and targeted deletion in transgenic mice has clearly demonstrated its importance in normal gut function. Enteric neuropathy is also often associated with abnormal NO production, for example in achalasia and diabetic gastroparesis. Not surprisingly therefore, aberrant nNOS activity is widely implicated in enteric disease, and represents a potential molecular target for therapeutic intervention. One physiological signaling mechanism of NO bioactivity is through chemical reaction with the heme center of guanylyl cyclase, resulting in the conversion of cGMP from GTP. This second messenger nucleotide signal activates cGMP-dependent protein kinases, phosphodiesterases, and ion channels, and is implicated in the neuronal control of GI function. However, few studies in the GI tract have fully related NO bioactivity with specific molecular targets of NO-derived signals. In the central nervous system (CNS), it is now increasingly appreciated that NO bioactivity is often actively transduced via S-nitrosothiol (SNO) signals rather than via activation of guanylyl cyclase. Moreover, aberrant S-nitrosylation of specific molecular targets is implicated in CNS pathology. S-nitrosylation refers to the post-translational modification of a protein cysteine thiol by NO, forming an endogenous SNO. Because cysteine residues are often key regulators of protein function, S-nitrosylation represents a physiologically important signaling mechanism analogous to other post-translational modifications, such as O-phosphorylation. This article provides an overview of how neurotransmitter NO is produced by nNOS as this represents the most prominent and well defined source of SNO production in the enteric nervous system. Further, it provides a perspective of how S-nitrosylation signals derived from multiple diverse sources may potentially transduce NO bioactivity in the GI tract. Possible lessons that might be learnt from the CNS, such as SNO mediated auto-inhibition of nNOS activity and modulation of neuronal cell death, are also explored as these may have pathophysiological relevance in enteric neuropathy. Thus, S-nitrosylation may mediate previously underappreciated NO-derived signals in the enteric nervous system that regulate homeostatic gut functions and disease susceptibility.
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PMID:S-nitrosothiol signals in the enteric nervous system: lessons learnt from big brother. 2144 85

Nitric oxide (NO), produced by the neural nitric oxide synthase enzyme (nNOS) is a transmitter of inhibitory neurons supplying the muscle of the gastrointestinal tract. Transmission from these neurons is necessary for sphincter relaxation that allows the passage of gut contents, and also for relaxation of muscle during propulsive activity in the colon. There are deficiencies of transmission from NOS neurons to the lower esophageal sphincter in esophageal achalasia, to the pyloric sphincter in hypertrophic pyloric stenosis and to the internal anal sphincter in colonic achalasia. Deficits in NOS neurons are observed in two disorders in which colonic propulsion fails, Hirschsprung's disease and Chagas' disease. In addition, damage to NOS neurons occurs when there is stress to cells, in diabetes, resulting in gastroparesis, and following ischemia and reperfusion. A number of factors may contribute to the propensity of NOS neurons to be involved in enteric neuropathies. One of these is the failure of the neurons to maintain Ca(2+) homeostasis. In neurons in general, stress can increase cytoplasmic Ca(2+), causing a Ca(2+) toxicity. NOS neurons face the additional problem that NOS is activated by Ca(2+). This is hypothesized to produce an excess of NO, whose free radical properties can cause cell damage, which is exacerbated by peroxynitrite formed when NO reacts with oxygen free radicals.
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PMID:The involvement of nitric oxide synthase neurons in enteric neuropathies. 2189 78


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