Neuromuscular diseases and disorders of the alimentary system

Neurological complications of bariatric surgery

Obesity is reaching pandemic proportions, and the number of bariatric surgeries is increasing. Neurological complications of bariatric procedures are more and more frequently reported and physicians need to recognize and be able to manage them. Neurological complications may result from mechanical or inflammatory mechanisms, but mainly from nutritional deficiencies. Vitamin B12, folate, thiamine, vitamin D, and vitamin E are the most frequent deficiencies. Different patterns of complications can be observed that may differ from time to presentation. At an early stage, immediate peripherical nerve injury, Wernicke's encephalopathy, and polyradiculoneuropathy are the most frequent. Late complications may appear after years and include optic neuropathy, myelopathy, peripherical neuropathy, and myopathy. Bariatric surgery patients should benefit from careful nutritional follow-up with routine monitoring of micronutrients at 6 weeks and 3, 6, and 12 months post-op and then annually after surgery, and multivitamin supplementation for life.

Review article: the assessment and management of chronic severe gastrointestinal dysmotility in adults

BACKGROUND

The characterisation and management of chronic severe gastrointestinal (GI) dysmotility are challenging. It may cause intestinal failure requiring home parenteral nutrition (HPN).

AIMS

To review the presentation, aetiology, characterisation, management and outcome of chronic severe GI dysmotility, and to suggest a pragmatic management algorithm.

METHODS

PubMed search was performed up to December 2012 using appropriate search terms, restricted to human articles and reviewed for relevance. Segmental dysmotility, acute ileus, functional syndromes and non-English articles were excluded. Evidence and recommendations were evaluated using the GRADE system.

RESULTS

In total, 721 relevant articles were reviewed. A coherent and definitive picture is hampered by overlapping classification systems using multi-modal characterisation methods, subject to pitfalls and some requiring further validation. The literature is confined to case series with no randomised trials. Fewer than 20% undergo full thickness jejunal biopsy, which are otherwise labelled idiopathic. However, in studies with up to 80% biopsy rates, neuromuscular abnormalities may be found in 90%. Between 14% and 50% will require HPN, comprising 8-14% of all HPN patients, of which 2/3 are primary/idiopathic and 1/3 secondary, with scleroderma being the leading secondary cause. Ten-year  mortality ranges from 13% to 35% and is worst in elderly scleroderma patients. Management includes limited treatments for secondary causes, prokinetics, symptom palliation, psychological support, nutrition, hydration and judicious surgery.

CONCLUSIONS

Severe dysmotility often remains idiopathic. It is rarely possible to alter disease trajectory; consequently, prognosis may be poor. Multi-disciplinary teams in a specialist setting can improve outcomes. Graded recommendations are enumerated and a pragmatic algorithm is suggested.

What every hospitalist should know about the post-bariatric surgery patient

Obesity is a growing worldwide epidemic, increasingly addressed through surgical options for weight loss. Benefits of these operations, such as weight loss and improvement or reversal of obesity-related comorbidities, are well established; however, postoperative complications do occur. This article will evaluate common causes for hospital admissions in the post-bariatric surgery population as they relate to the hospitalist who is often responsible for their care. Here we provide an overview of the most common bariatric procedures currently performed, early postoperative complications, late medical complications (ie, abdominal complaints, weight fluctuations, nutritional deficiencies, and metabolic bone disease), and late surgical complications that often affect these patients and result in hospital admissions. Special attention will be paid to radiologic pearls that can assist in the initial evaluation and diagnosis of these patients.

Muscular dystrophies at different ages: metabolic and endocrine alterations

Common metabolic and endocrine alterations exist across a wide range of muscular dystrophies. Skeletal muscle plays an important role in glucose metabolism and is a major participant in different signaling pathways. Therefore, its damage may lead to different metabolic disruptions. Two of the most important metabolic alterations in muscular dystrophies may be insulin resistance and obesity. However, only insulin resistance has been demonstrated in myotonic dystrophy. In addition, endocrine disturbances such as hypogonadism, low levels of testosterone, and growth hormone have been reported. This eventually will result in consequences such as growth failure and delayed puberty in the case of childhood dystrophies. Other consequences may be reduced male fertility, reduced spermatogenesis, and oligospermia, both in childhood as well as in adult muscular dystrophies. These facts all suggest that there is a need for better comprehension of metabolic and endocrine implications for muscular dystrophies with the purpose of developing improved clinical treatments and/or improvements in the quality of life of patients with dystrophy. Therefore, the aim of this paper is to describe the current knowledge about of metabolic and endocrine alterations in diverse types of dystrophinopathies, which will be divided into two groups: childhood and adult dystrophies which have different age of onset.

Gastrointestinal disorders in elderly patients

Gastrointestinal disorders are common in elderly patients, and the clinical presentation, complications, and management may differ from those in younger patient. Most impairment occurs in the proximal and distal tract of the gastrointestinal system. Swallowing abnormalities with a wide span of symptoms and pelvic floor pathologies involving all the pelvic compartments are common. Acute abdomen, often from small bowel obstruction or mesenteric ischemia, can pose a diagnostic challenge, because a mild clinical presentation may hide serious visceral involvement. In this setting, the radiologist often is asked to suggest the appropriate management options and to guide the management.

Implantable neural electrical stimulator for external control of gastrointestinal motility

Functional electrical stimulation has been suggested as a possible avenue for treating a variety of gastrointestinal motility-related disorders such as gastroparesis, chronic constipation and morbid obesity. The aims of the present study were to design a radio-frequency controlled multi-channel implantable neural gastrointestinal electrical stimulator and test it in an acute canine model. The stimulation parameters can be reprogrammed after implantation, allowing the execution of parametric studies and the investigation of their efficacy in producing controlled gastrointestinal contractions. Bipolar pulse trains of 50Hz frequency, 8-16V(pp) amplitude, 10-100% duty cycle, 1-120s duration, and 2s to 1h pause between successive stimulation sessions were delivered to the stomachs of nine dogs. The resulting contractions were measured by force transducers and digitally recorded on a personal computer. The acute studies confirmed the effectiveness of electrical stimulation in producing invoked gastric contractile activity under the control of the implantable neurostimulator.

Neurologic complications after surgery for obesity

Bariatric surgical procedures are increasingly common. In this review, we characterize the neurologic complications of such procedures, including their mechanisms, frequency, and prognosis. Literature review yielded 50 case reports of 96 patients with neurologic symptoms after bariatric procedures. The most common presentations were peripheral neuropathy in 60 (62%) and encephalopathy in 30 (31%). Among the 60 patients with peripheral neuropathy, 40 (67%) had a polyneuropathy and 18 (30%) had mononeuropathies, which included 17 (94%) with meralgia paresthetica and 1 with foot drop. Neurologic emergencies including Wernicke's encephalopathy, rhabdomyolysis, and Guillain-Barré syndrome were also reported. In 18 surgical series reported between 1976 and 2004, 133 of 9996 patients (1.3%) were recognized to have neurologic complications (range: 0.08-16%). The only prospective study reported a neurologic complication rate of 4.6%, and a controlled retrospective study identified 16% of patients with peripheral neuropathy. There is evidence to suggest a role for inflammation or an immunologic mechanism in neuropathy after gastric bypass. Micronutrient deficiencies following gastric bypass were evaluated in 957 patients in 8 reports. A total of 236 (25%) had vitamin B(12) deficiency and 11 (1%) had thiamine deficiency. Routine monitoring of micronutrient levels and prompt recognition of neurological complications can reduce morbidity associated with these procedures.