Emerging drugs for the treatment of gastroparesis

Decreased thalamic monoamine availability in drug-induced parkinsonism

Drug-induced parkinsonism (DIP) is caused by a dopamine receptor blockade and is a major cause of misleading diagnosis of Parkinson’s disease (PD). Striatal dopamine activity has been investigated widely in DIP; however, most studies with dopamine transporter imaging have focused on the clinical characteristics and prognosis. This study investigated differences in striatal subregional monoamine availability among patients with DIP, normal controls, and patients with early PD. Thirty-five DIP patients, the same number of age-matched PD patients, and 46 healthy controls were selected for this study. Parkinsonian motor status was examined. Brain magnetic resonance imaging and positron emission tomography with ¹⁸F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane were performed, and the regional standardized uptake values were analyzed with a volume-of-interest template and compared among the groups. The groups were evenly matched for age, but there were numerically more females in the DIP group. Parkinsonian motor symptoms were similar in the DIP and PD groups. Monoamine availability in the thalamus of the DIP group was lower than that of the normal controls and similar to that of the PD group. In other subregions (putamen, globus pallidus, and ventral striatum), monoamine availability in the DIP group and normal controls did not differ and was higher than that in the PD group. This difference compared to healthy subject suggests that low monoamine availability in the thalamus could be an imaging biomarker of DIP.

Diabetic Gastroparesis: Principles and Current Trends in Management

This article is a comprehensive review of diabetic gastroparesis, defined as delayed or disordered gastric emptying, including basic principles and current trends in management. This review includes sections on anatomy and physiology, diagnosis and differential diagnosis as well as management and current guidelines for treatment of diabetic gastroparesis. Diabetic gastroparesis (DGp) is a component of autonomic neuropathy resulting from long-standing poorly controlled type 1 and type 2 diabetes. The diagnostic workup of DGp first excludes obstruction and other causes including medications that may mimic delayed/disordered gastric emptying. Targeting nutrition, hydration, symptomatic relief and glycemic control are mainstays of treatment for DGp. Additionally, optimal treatment of DGp includes good glycemic management, often involving customizing insulin delivery using basal-bolus insulin and technology, including sensor-augmented pumps and continuous glucose monitoring systems. Prokinetic medications may be helpful in DGp symptoms, although only limited number of medications is currently available in the USA. Selected medication-refractory patients with DGp may benefit from gastric neuromodulation, and some from surgical interventions including pyloric therapies that can also be done endoscopically. As is true of any of the diabetic complications, prevention of DGp by early and optimal glycemic control is more cost-effective.Funding: Hansa Medcell, India.

Management of gastrointestinal complications in hereditary transthyretin amyloidosis: a single-center experience over 40 years

Hereditary transthyretin amyloidosis (ATTRm amyloidosis) is a rare disease caused by the deposition and accumulation of insoluble non-native transthyretin fibrils in the body. The disease inevitably results in widespread organ disruption, and poor life expectancy. The GI tract is one organ system vulnerable to disruption and, although the clinical presentation of the disease varies, GI involvement affects most patients with ATTRm amyloidosis. Areas covered: This article presents our experience with diagnosing and treating the GI symptoms of ATTRm amyloidosis patients at our center over the last 40 years, in the Swedish clustering area of the disease. Our aim is to help other physicians to better manage GI complications in patients with this rare but widespread condition. Expert commentary: GI symptoms are debilitating complications for ATTRm amyloidosis patients to experience, yet with the appropriate questioning and diagnosis methods, symptomatic treatments of these symptoms can be implemented to provide relief. Further, patients with fewer GI complications and a good nutritional status are also better candidates for liver transplantation which, in selected cases, is the best disease-modifying treatment of ATTRm amyloidosis to date.

Anamorelin hydrochloride in the treatment of cancer anorexia-cachexia syndrome: design, development, and potential place in therapy

Cancer anorexia–cachexia syndrome (CACS) is a complex and largely untreatable paraneoplastic complication common in advanced cancer. It is associated with profoundly deleterious effects on quality of life and survival. Since its discovery over a decade ago, anamorelin hydrochloride (anamorelin), a mimetic of the growth hormone secretagogue ghrelin, has shown considerable promise in ameliorating components of CACS when administered to patients with advanced cancer, including loss of lean body mass and reversal of anorexia. This review summarizes the development of anamorelin and its safety and efficacy in clinical investigations. The potential future role of anamorelin in treating CACS is also discussed.

Haloperidol undermining gastroparesis symptoms (HUGS) in the emergency department

BACKGROUND

Gastroparesis associated nausea, vomiting & abdominal pain (GP N/V/AP) are common presentations to the emergency department (ED). Treatment is often limited to antiemetic, prokinetic, opioid, & nonopioid agents. Haloperidol (HP) has been shown to have analgesic & antiemetic properties. We sought to evaluate HP in the ED as an alternative treatment of GP N/V/AP.

METHODS

Using an electronic medical record, 52 patients who presented to the ED w/GP N/V/AP secondary to diabetes mellitus and were treated w/HP were identified. Patients who received HP were compared to themselves w/the most recent previous encounter in which HP was not administered. ED length of stay (LOS), additional antiemetics/prokinetics administered, hospital LOS, and morphine equivalent doses of analgesia (ME) from each visit were recorded. Descriptive statistics, categorical (Chi Square Test or Z-Test for proportion) and continuous (Wilcoxon Signed Rank Test) comparisons were calculated. Statistical significance was considered for two tail p-values less than 0.05.

RESULTS

A statistically significant reduction in ME (Median 6.75 [IQR 7.93] v 10.75 [IQR12]: p=0.001) and reduced admissions for GP (5/52 v 14/52: p=0.02) when HP was administered was observed. There were no statistically significant differences in ED or hospital LOS, and additional antiemetics administered between encounters in which HP was administered and not administered. No complications were identified in patients who received HP.

CONCLUSIONS

The rate of admission and ME was found to be significantly reduced in patients with GP secondary to diabetes mellitus who received HP. HP may represent an appropriate, effective, and safe alternative to traditional analgesia and antiemetic therapy in the ED management of GP associated N/V/AP.

Pseudo-obstruction, stroke, and mitochondrial dysfunction: A lethal combination

OBJECTIVES

The m.3243A>G MTTL1 mutation is the most common cause of mitochondrial disease; yet there is limited awareness of intestinal pseudo-obstruction (IPO) in this disorder. We aimed to determine the prevalence, severity, and clinical outcome of patients with m.3243A>G-related mitochondrial disease manifesting with IPO.

METHODS

In this large, observational cohort study, we assessed the clinical, molecular, and radiological characteristics of patients with genetically determined m.3243A>G-related mitochondrial disease, who presented with severe symptoms suggestive of bowel obstruction in the absence of an occluding lesion.

RESULTS

Between January 2009 and June 2015, 226 patients harbouring the m.3243A>G mutation were recruited to the Medical Research Council Centre Mitochondrial Disease Patient Cohort, Newcastle. Thirty patients (13%) presented acutely with IPO. Thirteen of these patients had a preceding history of stroke-like episodes, whereas 1 presented 27 years previously with their first stroke-like episode. Eight patients developed IPO concomitantly during an acute stroke-like episode. Regression analysis suggested stroke was the strongest predictor for development of IPO, in addition to cardiomyopathy, low body mass index and high urinary mutation load. Poor clinical outcome was observed in 6 patients who underwent surgical procedures.

INTERPRETATION

Our findings suggest, in this common mitochondrial disease, that IPO is an under-recognized, often misdiagnosed clinical entity. Poor clinical outcome associated with stroke and acute surgical intervention highlights the importance of the neurologist having a high index of suspicion, particularly in the acute setting, to instigate timely coordination of appropriate care and management with other specialists. Ann Neurol 2016;80:686-692.

Progress in the treatment of small fiber peripheral neuropathy

Small fiber neuropathy is a syndrome of diverse disease etiology because of multiple pathophysiologic mechanisms with major presentations of neuropathic pain and autonomic symptoms. Over the past decade, there has been substantial progress in the treatments for neuropathic pain, dysautonomia and disease-modifying strategy. In particular, anticonvulsants and antidepressants alleviate neuropathic pain based on randomized clinical trials.

Gastric emptying and glycaemia in health and diabetes mellitus

The rate of gastric emptying is a critical determinant of postprandial glycaemia and, accordingly, is fundamental to maintaining blood glucose homeostasis. Disordered gastric emptying occurs frequently in patients with longstanding type 1 diabetes mellitus and type 2 diabetes mellitus (T2DM). A complex bidirectional relationship exists between gastric emptying and glycaemia--gastric emptying accounts for ∼35% of the variance in peak postprandial blood glucose concentrations in healthy individuals and in patients with diabetes mellitus, and the rate of emptying is itself modulated by acute changes in glycaemia. Clinical implementation of incretin-based therapies for the management of T2DM, which diminish postprandial glycaemia, in part by slowing gastric emptying, is widespread. Other therapies for patients with T2DM, which specifically target gastric emptying include pramlintide and dietary-based treatment approaches. A weak association exists between upper gastrointestinal symptoms and the rate of gastric emptying. In patients with severe diabetic gastroparesis, pathological changes are highly variable and are characterized by loss of interstitial cells of Cajal and an immune infiltrate. Management options for patients with symptomatic gastroparesis remain limited in their efficacy, which probably reflects the heterogeneous nature of the underlying pathophysiology.