Gastroparesis: A Review of Current Diagnosis and Treatment Options

Diabetic Gastroparesis and its Emerging Therapeutic Options: A Narrative Review of the Literature

Diabetic gastroparesis (DG) is one of the many complications of diabetes mellitus (DM). Even though this condition surfaces years after uncontrolled disease, it affects the quality of life in several ways and causes significant morbidity. Common symptoms experienced by the patients include postprandial nausea, vomiting, abdominal fullness, and pain. Strict glycemic control is essential to evade the effects of DG. The purpose of this review article is to briefly study the pathophysiology, clinical features, diagnostic modalities, and the effects of DG on different aspects of life. Furthermore, it also focuses on the emerging treatment modalities for DG. Tradipitant and relamorelin are two such treatment options that are gaining noteworthy recognition and are discussed in detail in this review article. As observed through various clinical trials, these drugs help alleviate symptoms like nausea, vomiting, abdominal pain, and bloating in patients suffering from DG, thereby targeting the most common and bothersome symptoms of the disease. This leads to an improvement in the quality of life, making it a reliable treatment option for this disease. But while pharmacological intervention is vital, psychological support and lifestyle changes are equally important and are the reason why a multidisciplinary approach is required for the treatment of DG.

Detecting and treating the protean manifestations of diabetic autonomic neuropathy

The manifestations of diabetic autonomic neuropathy (DAN) are protean and clinically involve multiple systems, including the cardiovascular system, the gastrointestinal system, the genitourinary system as well as the sweat glands (sudomotor dysfunction) and the gallbladder. In addition, cardiac autonomic neuropathy (CAN) is associated with a correctible inability to appreciate and correct hypoglycaemia. While not a clinical problem, pupillary involvement should be the clue and the catalyst to investigate for other manifestations of DAN. This review outlines a practical approach to detecting and investigating the manifestations of DAN. Of particular importance is early detection of cardiovascular involvement where prompt therapy through glycaemic control can decrease the severity of CAN and decelerate the frequency and severity of retinopathy and nephropathy in addition to decreasing cardiovascular events and mortality. CAN also plays a role in accelerating other diabetic complications such as acute ischaemic stroke, heart failure, medial artery calcinosis, foot ulcers, peripheral artery disease and Charcot joints. Many therapies of DAN are available, which should not only decrease morbidity and mortality from DAN, but also improve the patient's quality of life. However, the therapies available are largely symptomatic.

Health-care resource use and costs associated with diabetic and idiopathic gastroparesis: A claims analysis of the first 3 years following the diagnosis of gastroparesis

BACKGROUND

Due to limited treatment options, many patients with diabetic gastroparesis (DG) or idiopathic gastroparesis (IG) experience inadequate symptom control resulting in increased health-care resource utilization (HRU) and associated costs. We compared all-cause HRU and health-care costs over the 3 years after patients' first gastroparesis diagnosis with that of matched controls without gastroparesis.

METHODS

Newly diagnosed adults with DG or IG were identified in Optum's de-identified Clinformatics^® Data Mart Database (Q1-2007 to Q1-2019). Patients with DG/IG were matched 1:1 to controls using a mixed approach of exact matching and propensity score matching. The index date was the first gastroparesis diagnosis for cases or randomly selected for controls. All-cause HRU and direct health-care costs per person-year (PPY) were compared between DG/IG cases and controls in Years 1-3 post-index.

KEY RESULTS

Demographics and comorbidities were balanced between patients with gastroparesis (n = 18,015 [DG]; n = 14,305 [IG]) and controls. In each of the Years 1-3 post-index, patients with DG or IG had significantly higher annual HRU and costs versus controls (mean total cost differences PPY: DG Year 1 $34,885, Year 2 $28,071, Year 3 $25,606; IG Year 1 $23,176, Year 2 $16,627, Year 3 $14,396) (all p < 0.05). Across all 3 years, DG/IG cohorts had approximately twice the costs of controls. HRU and costs were highest in Year 1 post-index for both DG and IG.

CONCLUSIONS & INFERENCES

The economic burden of gastroparesis remains high several years after diagnosis, emphasizing the need for chronic treatment to effectively manage symptoms and consequently reduce the burden of this disorder.

Metopimazine is primarily metabolized by a liver amidase in humans

Metopimazine (MPZ) is a peripherally restricted, dopamine D2 receptor antagonist used for four decades to treat acute nausea and vomiting. MPZ is currently under clinical investigation for the treatment of gastroparesis (GP). MPZ undergoes high first-pass metabolism that produces metopimazine acid (MPZA), the major circulating metabolite in humans. Despite a long history of use, the enzymes involved in the metabolism of MPZ have not been identified. Here we report a series of studies designed to identify potential MPZ metabolites in vitro, determine their clinical relevance in humans, and elucidate the enzymes responsible for their formation. The findings demonstrated that the formation of MPZA was primarily catalyzed by human liver microsomal amidase. Additionally, human liver cytosolic aldehyde oxidase (AO) catalyzes the formation of MPZA, in vitro, although to a much lesser extent. Neither cytochrome P450 enzymes nor flavin-monooxygenases (FMO) were involved in the formation MPZA, although two minor oxidative pathways were catalyzed by CYP3A4 and CYP2D6 in vitro. Analysis of plasma samples from subjects dosed 60 mg of MPZ verified that these oxidative pathways are very minor and that CYP enzyme involvement was negligible compared to microsomal amidase/hydrolase in overall MPZ metabolism in humans. The metabolism by liver amidase, an enzyme family not well defined in small molecule drug metabolism, with minimal metabolism by CYPs, differentiates this drug from current D2 antagonists used or in development for the treatment of GP.

Efficacy and safety of gastric peroral endoscopic myotomy (G-POEM) for refractory gastroparesis: 3-year follow up results

BACKGROUND/PURPOSE

Gastroparesis is a common but easily overlooked disease. Gastric peroral endoscopic myotomy (G-POEM) is one of the third-space endoscopy techniques to treat gastroparesis. In this study, we aimed to evaluate the efficacy and safety of G-POEM for patients with refractory gastroparesis.

METHODS

Between December 2017 and 2020, we consecutively enrolled patients with gastroparesis who failed after the administration of several kinds of medication and repeated admission for nutritional support. All patients underwent gastric emptying scintigraphy and answered a questionnaire on Gastroparesis Cardinal Symptom Index (GCSI). Demographic data, endoscopic procedure, and post procedural outcome were analyzed.

RESULTS

A total of 11 (9 women and 2 men) patients with refractory gastroparesis (nine with diabetes mellitus, one systemic lupus erythematosus, and one idiopathic) were enrolled. The mean (±standard deviation (SD)) procedure time was 61.82 (±18.99) min with technical and clinical success rates of 100% and 81.82%, respectively. A statistically significant improvement was observed in the clinical severity (mean GCSI score 36.00 vs. 14.73, p < 0.0001) and gastric emptying time (mean T_1/2 341.92 vs. 65.92 min, p = 0.016) after G-POEM. Hospital stay was 7.18 (±4.49) days without mortality. Complications included 4 (36.36%) patients with self-limited postprocedural abdominal pain and 3 (27.27%) patients with intra-procedural pneumoperitoneum. During the mean follow-up period of 554.36 days, one (9.09%) patient had relapsed clinical symptoms after 6 months.

CONCLUSIONS

G-POEM is an efficient and safe pylorus-directed endoscopic therapy for refractory gastroparesis with promising results.

A Low Cost, Novel Treatment of Severe Diabetic Gastroparesis Based on Burkitt's Dietary Fiber Hypothesis

We report a seven-year follow-up of a 43-year-old Hispanic female with severe diabetic gastroparesis (GP) and a 42.5 kg weight loss (45% of body mass), who required feeding jejunostomy tube placement. The patient had an excellent response to a treatment regime directed at increasing stool bulk, enhancing gut transit, and mobilizing intestinal gas by using dietary fiber supplements and osmotic laxatives with as needed tap water enemas. Hospital cost savings for this patient exceeded $125,000 annually. This case study suggests that constipation may substantially contribute to GP.

Disorders of the brain-gut interaction and eating disorders

BACKGROUND

Eating disorders (ED) involve both the nervous system and the gastrointestinal tract. A similar double involvement is also found in disorders of the brain-gut interaction (DGBI) and symptoms are sometimes similar.

AIM

To find out where there is an association and a cause-effect relationship, we looked for the comorbidity of DGBI and ED.

METHODS

A systematic review was undertaken. A literature search was performed. Inclusion criteria for the articles retained for analysis were: Observational cohort population-based or hospital-based and case-control studies, examining the relationship between DGBI and ED. Exclusion criteria were: Studies written in other languages than English, abstracts, conference presentations, letters to the Editor and editorials. Selected papers by two independent investigators were critically evaluated and included in this review.

RESULTS

We found 29 articles analyzing the relation between DGBI and ED comprising 13 articles on gastroparesis, 5 articles on functional dyspepsia, 7 articles about functional constipation and 4 articles on irritable bowel syndrome.

CONCLUSION

There is no evidence for a cause-effect relationship between DGBI and ED. Their common symptomatology requires correct identification and a tailored therapy of each disorder.

Treatment Utilization and Socioeconomic Disparities in the Surgical Management of Gastroparesis

BACKGROUND

Gastroparesis is an end-organ sequela of diabetes. We evaluated the roles of race and socioeconomic status in hospitalization rates and utilization of surgical treatments in these patients.

METHODS

Data was extracted from the National Inpatient Sample (NIS) between the years 2012 and 2014, and any discharge diagnosis of gastroparesis (536.3) was included. Gastrostomy, jejunostomy, and total parenteral nutrition were considered nutritional support procedures, and procedures aimed at improving motility were considered definitive disease-specific procedures: pyloroplasty, endoscopic pyloric dilation, gastric pacemaker placement, and gastrectomy.

RESULTS

There were 747,500 hospitalizations reporting a discharge diagnosis of gastroparesis. On multivariable analysis, black race (OR 1.93, 95% CI 1.89-1.98; p < 0.001) and Medicaid insurance (OR 1.46, 95% CI 1.42-1.50; p < 0.001) were the strongest socioeconomic risk factors for hospitalization due to gastroparesis. Patients in urban teaching institutions were most likely to undergo a surgical intervention for gastroparesis (5.53% of patients versus 3.94% of patients treated in urban non-teaching hospitals and 2.38% of patients in rural hospitals; p < 0.001). Uninsured patients were less than half as likely to receive treatment compared to those with private insurance (OR 0.41, 95% CI 0.34-0.48; p < 0.001), and black patients had an OR 0.75 (95% CI 0.69-0.81; p < 0.001) for receiving treatment. Urban teaching hospitals had a twofold higher likelihood of intervention (OR 2.12, 95% CI 1.84-2.44; p < 0.001).

CONCLUSIONS

Marked racial and economic disparities exist in surgical distribution of care for gastroparesis, potentially driven by differences in utilization of care.

Gastroparesis: New insights into an old disease

Gastroparesis (Gp) is a chronic disease characterized by a delayed gastric emptying in the absence of mechanical obstruction. Although this condition has been reported in the literature since the mid-1900s, only recently has there been renewed clinical and scientific interest in this disease, which has a potentially great impact on the quality of life. The aim of this review is to explore the pathophysiological, diagnostic and therapeutical aspects of Gp according to the most recent evidence. A comprehensive online search for Gp was carried out using MEDLINE and EMBASE. Gp is the result of neuromuscular abnormalities of the gastric motor function. There is evidence that patients with idiopathic and diabetic Gp may display a reduction in nitrergic inhibitory neurons and in interstitial cells of Cajal and/or telocytes. As regards diagnostic approach, 99-Technetium scintigraphy is currently considered to be the gold standard for Gp. Its limits are a lack of standardization and a mild risk of radiation exposure. The C13 breath testing is a valid and safe alternative method. ¹³C acid octanoic and the ¹³C Spirulina platensis recently approved by the Food and Drug Administration are the most commonly used diagnostic kits. The wireless motility capsule is a promising technique, but its use is limited by costs and scarce availability in many countries. Finally, therapeutic strategies are related to the clinical severity of Gp. In mild and moderate Gp, dietary modification and prokinetic agents are generally sufficient. Metoclopramide is the only drug approved by the Food and Drug Administration for Gp. However, other older and new prokinetics and antiemetics can be considered. As a second-line therapy, tricyclic antidepressants and cannabinoids have been proposed. In severe cases the normal nutritional approach can be compromised and artificial nutrition may be needed. In drug-unresponsive Gp patients some alternative strategies (endoscopic, electric stimulation or surgery) are available.

Effect of Qihuang Decoction Combined with Enteral Nutrition on Postoperative Gastric Cancer of Nutrition and Immune Function

Objective

Early nutritional support in patients with gastric cancer can improve their nutritional status, but the impact on immune function has not been confirmed. This study aimed to analyze the effects of Qihuang decoction combined with enteral nutrition on nutrition and the immune function of postoperative gastric cancer.

Methods

120 patients with postoperative gastric cancer in the study group and 117 in the control group were selected as the study subjects from our hospital at random. Indications of nutrition and immune and the rates of complications were compared the day before surgery and 1, 3, 7, and 14 days after surgery.

Results

Indications of nutrition except hemoglobin (HB) in the study group were significantly higher than those before operation and the albumin (ALB) and prealbumin (TP) were significantly increased 7 and 14 days after surgery (P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 and P < 0.001 versus P < 0.001 and P < 0.001) and the protein (PA) 3, 7, and 14 days after surgery (P=0.011, P=0.002, and P=0.022) in the study group compared to those in the control group. Cellular and humoral immunity indications in the study group are significantly higher than those before operation compared to those in the control group, and the CD3⁺, CD4⁺, and CD4⁺/CD8⁺ were significantly increased 7 and 14 days after surgery (P=0.027 and P < 0.001 versus P=0.008 and P < 0.001 versus P=0.010 and P < 0.001) and IgA, IgG, and IgM 3, 7, and 14 days after surgery in the study group (P < 0.001, P < 0.001, and P < 0.001 versus P < 0.001, P < 0.002, and P < 0.001 versus P < 0.001, P < 0.001, and P < 0.001). The complications such as abdominal, lung, wound, and urinary infection were also significantly decreased (P^χ2=0.017; P < 0.001 and P < 0.001 versus P < 0.001 and P < 0.001) and the protein (PA) 3, 7, and 14 days after surgery (P=0.011, P=0.002, and P=0.022) in the study group compared to those in the control group. Cellular and humoral immunity indications in the study group are significantly higher than those before operation compared to those in the control group, and the CD3⁺, CD4⁺, and CD4⁺/CD8⁺ were significantly increased 7 and 14 days after surgery (P=0.027 and P < 0.001 versus P=0.008 and P < 0.001 versus P=0.010 and P < 0.001) and IgA, IgG, and IgM 3, 7, and 14 days after surgery in the study group (P < 0.001, P < 0.001, and P < 0.001 versus P < 0.001, P < 0.002, and P < 0.001 versus P < 0.001, P < 0.001, and P < 0.001). The complications such as abdominal, lung, wound, and urinary infection were also significantly decreased (P^χ2=0.017; P < 0.001 and P < 0.001 versus P < 0.001 and P < 0.001) and the protein (PA) 3, 7, and 14 days after surgery (P=0.011, P=0.002, and P=0.022) in the study group compared to those in the control group. Cellular and humoral immunity indications in the study group are significantly higher than those before operation compared to those in the control group, and the CD3⁺, CD4⁺, and CD4⁺/CD8⁺ were significantly increased 7 and 14 days after surgery (P=0.027 and P < 0.001 versus P=0.008 and P < 0.001 versus P=0.010 and P < 0.001) and IgA, IgG, and IgM 3, 7, and 14 days after surgery in the study group (P < 0.001, P < 0.001, and P < 0.001 versus P < 0.001, P < 0.002, and P < 0.001 versus P < 0.001, P < 0.001, and P < 0.001). The complications such as abdominal, lung, wound, and urinary infection were also significantly decreased (P^χ2=0.017; P < 0.001 and P < 0.001 versus P < 0.001 and P < 0.001) and the protein (PA) 3, 7, and 14 days after surgery (P=0.011, P=0.002, and P=0.022) in the study group compared to those in the control group. Cellular and humoral immunity indications in the study group are significantly higher than those before operation compared to those in the control group, and the CD3⁺, CD4⁺, and CD4⁺/CD8⁺ were significantly increased 7 and 14 days after surgery (P=0.027 and P < 0.001 versus P=0.008 and P < 0.001 versus P=0.010 and P < 0.001) and IgA, IgG, and IgM 3, 7, and 14 days after surgery in the study group (P < 0.001, P < 0.001, and P < 0.001 versus P < 0.001, P < 0.002, and P < 0.001 versus P < 0.001, P < 0.001, and P < 0.001). The complications such as abdominal, lung, wound, and urinary infection were also significantly decreased (P^χ2=0.017; P^χ2=0.036; P^χ2=0.041; P^χ2=0.004).

Conclusions

Qihuang decoction combined with enteral nutrition can promote the absorption of enteral nutrition with improving the immune and reducing complications of infection.

Proximal and Distal Gastric Retention Patterns in Gastroparesis and the Impact of Gastric Per-Oral Endoscopic Myotomy: A Retrospective Analysis Using Gastric Emptying Scintigraphy

Gastroparesis is a debilitating disease of insufficient gastric emptying and visceral hypersensitivity characterized by nausea, vomiting, early satiety, and bloating. Gastric emptying scintigraphy (GES), in combination with typical symptoms and normal esophagogastroduodenoscopy findings, is used to diagnose the disease. Gastric per-oral endoscopic pyloromyotomy (G-POEM) has emerged as a novel technique for treating gastroparesis, with up to an 80% success rate. This procedure involves myotomy of the distal stomach. We hypothesize that responders to this therapy are characterized by more distal dysmotility than nonresponders, as defined by GES retention patterns. Methods: We used regional gastric emptying measurements from diagnostic GES to determine the proximal or distal predominance of disease for each patient. We then compared treatment response and symptoms in each patient to total gastric half-emptying time (T_½), proximal gastric T_½, and a ratio comparing the 2 values. Results: In total, 47 patients underwent G-POEM during the study period. A significant difference (P < 0.01) was found in proximal-to-total T_½ ratio between responders and nonresponders. A significant difference between pre- and postprocedural proximal-to-total T_½ ratios was identified for each patient. No correlations were identified between motility patterns and symptoms or in motility patterns among the different etiologies of the disease. Conclusion: Proximal-to-total T_½ ratio may represent an important patient selection factor for G-POEM versus other treatment modalities going forward. Local retention patterns in GES may not inform the symptom profile in gastroparesis.

2007-2019: a "Third"-Space Odyssey in the Endoscopic Management of Gastrointestinal Tract Diseases

PURPOSE OF REVIEW

The main scope of this review article is to introduce readers to the innovative field of third-space endoscopy and offer a closer look at its history, milestones, and procedure spectrum while discussing ongoing and future challenges arising from its increasing adoption worldwide.

RECENT FINDINGS

Over the past few years, third-space endoscopy has been utilized in various diagnostic and interventional procedures performed throughout the gastrointestinal tract: obliteration of Zenker's diverticulum, myotomy for achalasia, gastroparesis or Hirschsprung's disease, biopsy or removal of subepithelial tumors, stricture management, post-per-oral endoscopic myotomy endoscopic fundoplication, and mediastino-, thoraco-, and peritoneoscopy. Third-space endoscopic interventions have revolutionized the management of esophageal motility disorders, gastroparesis, and gastrointestinal tract subepithelial tumors. Despite the high efficacy and safety of such interventions, some common (e.g., the high level of necessary endoscopic skill) and unique for each procedure (e.g., post-procedure gastroesophageal reflux or poor outcomes in patient subgroups) challenges still remain. Through a dedicated endoscopic training, a rigorous pre-procedure patient evaluation and selection, and the application of modified or new techniques, challenges can be overcome thus establishing existing procedures and paving the way for additional breakthroughs in the field of third-space endoscopy.

Gastric Emptying Scintigraphy Before Gastric per Oral Endoscopic Myotomy: Imaging May Inform Treatment

Gastric emptying scintigraphy (GES) helps to diagnose gastroparesis and is typically only used for whole stomach retention patterns. However, it may provide significantly more information when looking specifically at proximal and distal retention patterns. This article reviews global GES changes following gastric per oral endoscopic myotomy; how global, proximal, and distal GES measurements correlate to gastroparesis symptoms; and how proximal and distal GES may serve as proxies for the various mechanisms involved in gastroparesis. The authors' data on how GES may be used to select which patients will have success from G-POEM is also reviewed.

Gastrointestinal Neuropathies: New Insights and Emerging Therapies

The bewildering complexity of the enteric nervous system makes it susceptible to develop a wide array of motility disorders, collectively called enteric neuropathies. These gastrointestinal conditions are among the most challenging to manage, mainly given poor characterization of their etiopathophysiology and outcomes. Not surprisingly, therefore, targeted or curative therapies for enteric neuropathies are lacking and management is largely symptomatic. Nonetheless, recent advances in neurogastroenterology have witnessed improvements in established strategies, such as intestinal transplantation and the emergence of new treatments including novel drugs, electrical pacing, and manipulation of fecal microbiota, as well as stem cell and gene therapy.

Delayed Gastric Emptying Following Laparoscopic Repair of Very Large Hiatus Hernias Impairs Quality of Life

BACKGROUND

Delayed gastric emptying (DGE) following hiatus hernia surgery may affect a substantial number of patients with adverse clinical consequences. Here, we aim to evaluate the impact of DGE following laparoscopic repair of very large hiatus hernias on patients' quality of life, gastrointestinal symptomatology, and daily function.

METHODS

Analysis of data collected from a multicenter prospective randomised trial of patients who underwent laparoscopic mesh versus sutured repair of very large hiatus hernias (>50% of stomach in chest). DGE was defined as gastric food retention visualised at endoscopy after 6 h of fasting at 6 months post-surgery. Quality of life (QOL), gastrointestinal symptomatology, and daily function were assessed with the SF-36 questionnaire, Visick scoring and structured surveys administered prior to surgery and at 1, 3, 6 and 12 months after surgery.

RESULTS

Nineteen of 102 (18.6%) patients had DGE 6 months after surgery. QOL questionnaires were completed in at least 80% of patients across all time points. Compared with controls, the DGE group demonstrated significantly lower SF-36 physical component scores, delayed improvement in health transition, more adverse gastrointestinal symptoms, higher Visick scores and a slower rate of return to normal daily activities. These differences were still present 12 months after surgery.

CONCLUSIONS

DGE following large hiatus hernia repair is associated with a negative impact on quality of life at follow-up to 12 months after surgery.

Gastric Enterovirus Infection: A Possible Causative Etiology of Gastroparesis

BACKGROUND

Gastroparesis (GP) is a disabling chronic gastroenterologic disorder with high morbidity that severely impacts patients' quality of life. GP can present acutely after a viral-like gastrointestinal illness resulting in speculation that in some patients, neurologic damage caused by the infection might underlie the pathogenesis of idiopathic gastroparesis (IGP).

AIMS

The aim of this study is to document case reports of Enterovirus (EV) infection as a possible cause of IGP.

METHODS

Eleven patients referred with a diagnosis of GP underwent workup to exclude known causes of GP. Those with a history of flu-like symptoms or gastroenteritis prior to onset of GP symptoms had gastric biopsies taken during upper endoscopy to assess for the presence of gastric mucosal EV infection. Data on presenting symptoms, extra-intestinal symptoms and conditions, prior nutritional support requirements, upper endoscopy findings, and response to therapy were cataloged.

RESULTS

Eleven patients were diagnosed as IGP. Nine had active EV infection on gastric biopsies and were included (7/9 female, mean age 43 years). Eight out of nine received EV treatment with antivirals and/or immune therapies, with a wide degree of variability in treatment regimens. Four out of eight who received EV treatment had symptomatic improvement. One patient had stable symptoms. Three patients are currently undergoing therapy.

CONCLUSIONS

Gastric EV infection was frequently detected (82 %) in patients undergoing investigation for IGP. Antiviral and/or immune therapies against EV seem to be favorable, as most of our patients had resolution of their GP symptoms after treatment. This is the first study to identify EV as a possible infectious etiology of IGP.

Clinical aspects of neurointestinal disease: Pathophysiology, diagnosis, and treatment

The enteric nervous system (ENS) is involved in the regulation of virtually all gut functions. Conditions referred to as enteric neuropathies are the result of various mechanisms including abnormal development, degeneration or loss of enteric neurons that affect the structure and functional integrity of the ENS. In the past decade, clinical and molecular research has led to important conceptual advances in our knowledge of the pathogenetic mechanisms of these disorders. In this review we consider ENS disorders from a clinical perspective and highlight the advancing knowledge regarding their pathophysiology. We also review current therapies for these diseases and present potential novel reparative approaches for their treatment.

The Vomiting Patient: Small Bowel Obstruction, Cyclic Vomiting, and Gastroparesis

Vomiting and abdominal pain are common in patients in the emergency department. This article focuses on small bowel obstruction (SBO), cyclic vomiting, and gastroparesis. Through early diagnosis and appropriate management, the morbidity and mortality associated with SBOs can be significantly reduced. Management of SBOs involves correction of physiologic and electrolyte disturbances, bowel rest and removing the source of the obstruction. Treatment of acute cyclic vomiting is primarily directed at symptom control, volume and electrolyte repletion, and appropriate specialist follow-up. The mainstay of therapy for gastroparesis is metoclopramide.

Current and Emerging Medical Therapies for Gastroparesis

OPINION STATEMENT

Gastroparesis likely involves various pathophysiological disorders and is increasingly prevalent as complications of surgeries, medications, and chronic diabetes. Key to diagnosis is evidence of delayed gastric emptying, generally based on standardized scintigraphy, and ruling out distal obstruction or other dysmotilities. Initial medical management includes reviewing potentially exacerbating medications and ruling out other reversible causes, achieving tighter glucose control in diabetics, and implementing dietary and lifestyle changes. While current available medications are limited, symptomatic control is aimed at improving gastric emptying, alleviating nausea and vomiting, and treating associated abdominal pain. Other potential therapies are aimed at reducing acid production, improving gastric accommodation or pyloric dysfunction, and treating bacterial overgrowth. Future studies should be aimed toward identification of subpopulations of gastroparetics who are better responders to the various medications based on differences in underlying pathophysiology and adopting standardized study end point measures that may allow for comparisons across trials. This chapter will review current treatment options, upcoming promising medications, and some of the hurdles in advancing the field forward.

Role of estrogen in diabetic gastroparesis

Gastroparesis is a highly prevalent chronic disorder of the stomach, which is characterized by delayed gastric emptying and accompanied by a series of upper gastrointestinal symptoms. Diabetic gastroparesis (DGP) is one of the severe complications of diabetes, seriously affecting the patient's quality of life. At present, the pathogenesis of DGP is still unclear. The majority of DGP patients are women, and women's symptoms change with the fluctuation of the level of estrogen. Therefore, we speculate that estrogen may play an vital role in the stomach motility. Gastric emptying is an objective index for the diagnosis of gastroparesis. This article reviews the role of estrogen in DGP and the possible mechanisms.