Neurologic complications of bariatric surgery

Nutritional Neuropathies

OBJECTIVE

This article reviews the etiologies, presentations, and management of neuropathies related to nutritional deficiencies.

LATEST DEVELOPMENTS

Peripheral neuropathy can be the predominant or only manifestation of certain nutrient deficiencies. Cognitive difficulties or involvement of other parts of the central nervous system, such as the optic nerve and spinal cord, may accompany nutritional peripheral neuropathies. In most patients, the nutritional deficiency may have a single predominant cause, but in some cases, multiple causes may coexist. Obesity, for unclear reasons, can be associated with nutrient deficiencies. The rising rates of bariatric surgery and the incidence of nutrient deficiencies following bariatric surgery make this a particularly relevant topic for neurologists.

ESSENTIAL POINTS

Neuropathies caused by nutrient deficiencies are preventable with appropriate supplementation in high-risk situations. Early recognition and prompt treatment are essential to ensure an optimal outcome and minimize neurologic morbidity.

Prevalence of vasovagal syncope following bariatric surgery

BACKGROUND

Obesity is a major global public health problem. Observational studies have shown an increasing incidence of syncope and pre-syncope following bariatric surgery in obese patients. However, there is paucity of the true incidence of syncope following bariatrics sugary in the literature.

METHODS

We have randomly surveyed 200 patients who underwent bariatric surgery between 2016-2018 using Calgary Syncope Score (CSS).

RESULTS

Of the 200 patients enrolled, 107 (53.5%) were female with 167 patients (83.5%) between 18 and 50 years of age. The most-reported comorbidities were diabetes mellitus 26 (13%) hypertension 25 (12.5%) and pulmonary disease 18 (9%). The majority 98 (49%) of the patients had pre-operative body mass index (BMI) of 40-50 kg/m 2, and most of them had laparoscopic sleeve gastrectomy (LSG). Sixty-two (31%) patients had vasovagal syncope (VVS), 52 (26%) patients had non-VVS and 86 (43%) had no syncope.

CONCLUSION

Vasovagal syncope in patients following bariatric sugary is quite common and affects 15% of bariatric patients in our series in the first year postoperatively. Further randomized controlled trials are required to prove our results.

Classification and differential diagnosis of Wilson's disease

Wilson's disease is characterized by hepatic and extrapyramidal movement disorders (EPS) with variable manifestation primarily between age 5 and 45. This variability often makes an early diagnosis difficult. A classification defines different clinical variants of Wilson's disease, which enables classifying the current clinical findings and making an early tentative diagnosis. Until the unequivocal proof or an autosomal recessive disorder of the hepatic copper transporter ATP7B has been ruled out, differential diagnoses have to be examined. Laboratory-chemical parameters of copper metabolism can both be deviations from the norm not related to the disease as well as other copper metabolism disorders besides Wilson's disease. In addition to known diseases such as Menkes disease, occipital horn syndrome (OHS), Indian childhood cirrhosis (ICC) and ceruloplasmin deficiency, recently discovered disorders are taken into account. These include MEDNIK syndrome, Huppke-Brendel syndrome and CCS chaperone deficiency. Another main focus is on differential diagnoses of childhood icterus correlated with age and anaemia as well as disorders of the extrapyramidal motor system. The Kayser-Fleischer ring (KFR) is qualified as classical ophthalmologic manifestation. The recently described manganese storage disease presents another rare metabolic disorder with symptoms similar to Wilson's disease. As this overview shows, Wilson's disease fits into a broad spectrum of internal and neurological disease patterns with icterus, anaemia and EPS.

An overview of complications affecting the Central Nervous System following bariatric surgery

Bariatric surgery has been considered as an effective treatment for morbid obesity. Apart from procedures related complications, a broad spectrum of neurological disorders affecting any part of neuraxis has been reported following BS. Central nervous system complications, although less common than peripheral nervous system complications, carry significant morbidity and potential mortality. Encephalopathy, behavioral and psychiatric disorders, myelopathy and optic neuropathy are the most frequently reported CNS complications. Early detection and prompt management may improve or completely reverse these neurological complications. It is essential that the treating physicians must be aware of their clinical manifestations and management, so early diagnosis and treatment can prevent patients from suffering significant neurological deficits and even death. This review discusses the clinical manifestations of these complications in detail which will help concerned physician in earlier recognition and hence prevent the delay in specific treatment.

Copper deficiency, a new triad: anemia, leucopenia, and myeloneuropathy

Clinical copper deficiency is now more frequently recognized. Hematologically, it can present as anemia (microcytic, normocytic, or macrocytic) and neutropenia. Thrombocytopenia is relatively rare. Neurologically, it can manifest as myelopathy and peripheral neuropathy simulating subacute combined degeneration. Bone marrow findings can mimic myelodysplasia resulting in occasional inappropriate referral for bone marrow transplantation. Other conditions with similar presentations include infections, drug toxicity, autoimmunity, B₁₂ deficiency, folate deficiency, myelodysplastic syndrome, aplastic anemia, and lymphoma with bone marrow involvement. Hematological, but not neurological, manifestations respond promptly to copper replacement, making early diagnosis essential for good outcome. Common risk factors for copper deficiency are foregut surgery, dietary deficiency, enteropathies with malabsorption, and prolonged intravenous nutrition (total parenteral nutrition). We present a unique case of copper deficiency, with no apparent known risk factors.

Bariatric Surgery and the Neuro-Ophthalmologist

BACKGROUND

As the prevalence of obesity increases, so, too, do the prevalences of weight-related diseases and surgical procedures to promote weight loss. It is important for neuro-ophthalmologists to be familiar with these procedures and possible downstream effects on afferent and efferent visual function.

EVIDENCE ACQUISITION

Review of ophthalmology, neurology, general surgery, obesity, endocrinology, nutrition, psychiatry, and neurosurgery literature.

RESULTS

Bariatric surgery is a safe and effective treatment for weight loss in obese individuals. There is Level IV evidence that it is associated with improvement in idiopathic intracranial hypertension (IIH). Laboratory nutrient deficiencies are common following some types of bariatric procedures. Symptomatic deficiencies are less common but can be devastating. Thiamine deficiency can cause nystagmus and other symptoms in weeks to months after surgery, whereas B12 or copper deficiency can cause optic neuropathy in years to decades following bariatric surgery.

CONCLUSIONS

Bariatric surgery is a potential treatment for IIH. Postoperative vitamin deficiencies may cause nystagmus, optic neuropathy, nyctalopia, and/or ophthalmoparesis weeks to years after surgery.