Wernicke encephalopathy in subjects undergoing restrictive weight loss surgery: a systematic review of literature data

Advancements in Bariatric Surgery: A Comparative Review of Laparoscopic and Robotic Techniques

This article examines the evolution of bariatric surgery, with a focus on emerging technologies such as robotics and laparoscopy. In the case of gastric bypass, no significant differences have emerged between the two techniques in terms of hospitalization duration, weight loss, weight regain, or 30-day mortality. Robotic surgery, while requiring more time in the operating room, has been associated with lower rates of bleeding, mortality, transfusions, and infections. In revisional bariatric surgery, the robotic approach has shown fewer complications, shorter hospital stays, and a reduced need for conversion to open surgery. In the case of sleeve gastrectomy, robotic procedures have required more time and longer postoperative stays but have recorded lower rates of transfusions and bleeding compared to laparoscopy. However, robotic surgeries have proven to be more costly and potentially more complex in terms of postoperative complications. The review has also addressed the topic of the single-anastomosis duodeno-ileal switch (SADIS), finding comparable results between robotic and laparoscopic techniques, although robotic procedures have required more time in the operating room. Robotic technology has proven to be safe and effective, albeit with slightly longer operative times in some cases.

One-anastomosis gastric bypass (OAGB) versus Roux-en-Y gastric bypass (RYGB) as revisional procedures after failed laparoscopic sleeve gastrectomy (LSG): systematic review and meta-analysis of comparative studies

INTRODUCTION

The aim of this study was to compare weight loss and gastroesophageal reflux disease (GERD) remission after one-anastomosis gastric bypass (OAGB) versus Roux-en-Y gastric bypass (RYGB) as revisional procedures after laparoscopic sleeve gastrectomy (LSG).

METHODS

In PubMed, Embase, and Cochrane Library, a search was performed using the terms "Roux-en-Y gastric bypass versus one anastomosis gastric bypass," "revisional surgery," and "sleeve gastrectomy." Only original articles in English language comparing OAGB and RYGB were included. No temporal interval was set. The primary outcome measure was weight loss (%TWL). The secondary endpoints were leak, bleeding, marginal ulcer, and GERD. PRISMA flowchart was used. Differences in continuous and dichotomous outcome variables were expressed as mean difference (MD) and risk difference (RD) with 95% CI, respectively. Heterogeneity was assessed by using I2 statistic.

RESULTS

Six retrospective comparative articles were included in the present meta-analysis. Weight loss analysis showed a MD = 5.70 (95% CI 4.84-6.57) in favor of the OAGB procedure with a statistical significance (p = 0.00001) and no significant statistical heterogeneity (I2 = 0.00%). There was no significant RD for leak, bleeding, or marginal ulcer after the two revisional procedures. After conversion to OAGB, remission from GERD was 68.6% (81/118), and it was 80.6% (150/186) after conversion to RYGB with a RD = 0.10 (95% CI -0.04, 0.24), no statistical significance (p = 0.19), and high heterogeneity (I2 = 96%). De novo GERD was 6.3% (16/255) after conversional OAGB, and it was 0.5% (1/180) after conversion to RYGB with a RD = -0.23 (95% CI -0.57, 0.11), no statistical significance (p = 0.16), and high heterogeneity (I2 = 92%).

Comment on Wijnia, J.W. A Clinician's View of Wernicke-Korsakoff Syndrome. J. Clin. Med. 2022, 11, 6755

We have read with great interest the article by Wijnia [...].

Micronutrients Deficiencies in Candidates of Bariatric Surgery: Results from a Single Institution over a 1-Year Period

BACKGROUND

Micronutrient deficiencies represent a common condition after bariatric surgery (BS). The prevalence of these nutritional disorders before BS is still debated. The aim of our study was to retrospectively evaluate the prevalence of micronutrient deficiencies in candidates for BS.

METHODS

A prospectively maintained database of our institution was searched to find all patients who underwent surgery between January and December 2021. The following data were collected: age, gender, body mass index (BMI), obesity-associated diseases, and preoperative serum levels of vitamin B12, folate, and vitamin D.

RESULTS

A total of 174 patients were included in our study. Mean age and BMI were 39.2 ± 11.4 years and 44.3 ± 7.1 kg/m², respectively. One hundred and thirty-nine patients (79.9%) had at least one preoperative micronutrient disorder, with vitamin D deficiency being the most common (116, 66.7%), followed by a deficit of folate (76, 43.7%) and vitamin B12 (10, 5.7%). Forty-seven (27%) individuals had insufficient levels of vitamin D. Comparison of deficiencies between sexes showed that vitamin B12 < 20 ng/ml was significantly more frequent in women (p = 0.03). DLP showed a mild significant effect on folate levels (p = 0.01), while the association of HNT and T2DM had a mild significant effect on vitamin B12 (p = 0.02).

CONCLUSIONS

Preoperative micronutrient deficiencies were frequently found in candidates for BS. Approximately 90% of patients had deficient or insufficient serum levels of vitamin D preoperatively. Almost half of the patients had a preoperative deficit of folate, and vitamin B12 deficiency was significantly more frequent in the female population. It is mandatory to screen all patients undergoing BS for vitamin deficiencies before surgery.

Peripapillary Retinal Haemorrhages in Wernicke's Encephalopathy Following Bariatric Surgery in a Young Patient

Wernicke's encephalopathy (WE) is an acute neuropsychiatric syndrome resulting from thiamine deficiency (vitamin B₁). It is characterised classically by a triad of ophthalmoplegia, confusion, and ataxia. WE is classically associated with alcoholism but increasingly has been observed due to other causes, particularly in undernourished post-bariatric surgery patients. Herein, we describe a case of WE following laparoscopic sleeve gastrectomy in a young male patient who presented with binocular horizontal diplopia and was found to have preretinal peripapillary haemorrhages. This case raises the awareness that posterior segment findings can occur in WE but have been under-reported previously.

Dry beriberi after sleeve gastrectomy: An undiagnosed case report

INTRODUCTION AND IMPORTANCE

Sleeve gastrectomy (SG) is a popular surgery for morbid obesity because of minimal complications, while somewhere uncommon micronutrient deficiencies occur that make problems. One of these rare complications is dry beriberi (BB).

CASE PRESENTATION

A 20-year-old girl with obesity that a few months after SG had non-specific symptoms like nausea, vomiting, debilitating weakness, burning, and tingling in her feet, which led to more tests and imaging and confused the physicians. During the next two months, she had a 40 kg weight loss. The critical test that helped diagnosis was Electromyography and Nerve Conduction Velocity (EMG/NCV), which showed subacute axonal sensory-motor polyneuropathy and decreased level of vitamin B1, proved the patient's diagnosis was dray BB.

CLINICAL DISCUSSION

SG may contribute to vitamin and trace elements deficiency development. One of the micronutrients that deficiencies can disturb the patient is vitamin B1 deficiency. Vitamin B1 deficiencies could be demonstrated with peripheral polyneuropathy, beriberi, or Wernicke-Korsakoff syndrome. Based on decreased vitamin B1 and EMG/NCV results, the diagnosis had been dry beriberi corrected with supplement therapy.

CONCLUSION

Thiamine deficiency should be suspected in all patients with vomiting, neurological symptoms, and rapid weight loss post-bariatric surgery (BS), even after restrictive surgery. Especially when a patient reports substantial weight loss and vomiting in short order. Hopefully, this case report will make any patient hospitalized with similar conditions evaluated for beriberi and again multivitamin supplementation therapy after SG is emphasized.

Micronutrient status in bariatric surgery patients receiving postoperative supplementation per guidelines: Insights from a systematic review and meta-analysis of longitudinal studies

The micronutrient status and optimal monitoring schedule after bariatric surgery have not been sufficiently assessed. This systematic review and meta-analysis investigated the longitudinal changes in micronutrient status after bariatric surgery. PubMed, EMBASE, and Cochrane Library were searched for articles that measured preoperative and postoperative serum micronutrient levels in patients undergoing Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG). Among guideline-adherent studies, the longitudinal changes in micronutrient status were investigated using weighted mean difference (WMD) using a random-effects model. Among the 82 included studies, the guideline adherence rates for micronutrient supplementation after bariatric surgery did not exceed 20%. In patients supplemented per guidelines, vitamin A significantly decreased after RYGB by -7.54 (95% confidence interval [CI], -10.16 to -4.92) μg/dl at 12-23 months, vitamin E decreased after RYGB by -2.35 (95% CI, -3.65 to -1.05) μg/dl at ≥24 months, and ferritin by -54.93 (95% CI, -77.19 to -32.67] μg/L at ≥24 months after SG, compared with baseline, with moderate level of evidence. Significant decreases in micronutrient levels at certain follow-up intervals in studies with supplementation per guidelines need to be considered to establish a post-bariatric micronutrient monitoring schedule for timely detection and management of micronutrient deficiencies.

The Effects of Bariatric Surgery on Vitamin B Status and Mental Health

Diet is a modifiable factor that ensures optimal growth, biochemical performance, improved mood and mental functioning. Lack of nutrients, notably vitamin B, has an impact on human health and wellbeing. The United Arab Emirates is facing a serious problem of micronutrient deficiencies because of the growing trend for bariatric surgery, including Roux-en-Y gastric bypass and sleeve gastrectomy. People undergoing bariatric surgery are at high risk of developing neurological, cognitive, and mental disabilities and cardiovascular disease due to deficiency in vitamin B. Vitamin B is involved in neurotransmitter synthesis, including γ-aminobutyric acid, serotonin, dopamine, and noradrenaline. Deficiency of vitamin B increases the risk of depression, anxiety, dementia and Alzheimer's disease. In addition, vitamin B deficiency can disrupt the methylation of homocysteine, leading to hyperhomocysteinemia. Elevated homocysteine levels are detrimental to human health. Vitamin B deficiency also suppresses immune function, increases the production of pro-inflammatory cytokines and upregulates NF-κB. Considering the important functions of vitamin B and the severe consequences associated with its deficiency following bariatric surgery, proper dietary intervention and administration of adequate supplements should be considered to prevent negative clinical outcomes.

Non-alcoholic beriberi, Wernicke encephalopathy and long-term eating disorder: case report and a mini-review

INTRODUCTION

Nowadays, reports of beriberi are rare in developed countries. Wernicke encephalopathy may be present in about 25% of patients with beriberi.

CASE REPORT

We report the case of a woman with history of depression and chronic eating disorder, who complained Wernicke encephalopathy and beriberi. Sural nerve and muscular biopsy were performed, showing severe axonal neuropathy. Thiamine supplementation was started with rapid improvement of the pulmonary and cardiac affections; improvement of peripheral neuropathy was incomplete.

CONCLUSIONS

Thiamine deficiency can be misdiagnosed. Beriberi is an important cause of acute flaccid paralysis; hence, clinicians should consider this diagnosis and prompt start thiamine treatment to avoid permanent neurological sequelae.

Isolated Pulvinar/Hockey Stick Sign in Nonalcoholic Wernicke's Encephalopathy

BACKGROUND Wernicke's encephalopathy (WE), a commonly misdiagnosed and underdiagnosed pathology, presents with altered mental status, ataxia, and ophthalmoplegia. WE is most commonly caused by excessive alcohol use, but also has diverse nonalcoholic etiologies. Here we describe 2 cases of nonalcoholic WE with different etiologies that were initially misdiagnosed due to lack of correlation of magnetic resonance imaging (MRI) findings with clinical information. CASE REPORT Patient A, a 50-year-old woman with recent gastric sleeve surgery, presented with horizontal gaze-evoked nystagmus, ataxia, and altered mental status. MRI fluid-attenuated inversion recovery (FLAIR) revealed isolated bilateral, symmetrical, thalamic hyperintensities, initially diagnosed as variant Creutzfeldt-Jakob disease. A review of imaging and clinical presentation provided an alternate diagnosis of nonalcoholic WE secondary to nutritional deficiency. Intravenous (IV) thiamine improved symptoms with resolution of MRI findings 6 months later. Patient B, a 64-year-old woman, presented with nausea, vomiting, dizziness, altered mental status, and weight loss. MRI FLAIR revealed isolated bilateral, symmetrical, thalamic hyperintensities, initially determined to be ischemia, prompting stroke management. A diagnosis of nonalcoholic WE was suggested, given the patient's low thiamine levels and history of malnutrition, and was confirmed by her excellent therapeutic response to IV thiamine. CONCLUSIONS Nonalcoholic WE remains a challenging diagnosis because of the variable clinical presentation, myriad of underlying etiologies, and lack of standardized diagnostic laboratory tests. A multidisciplinary approach with close collaboration between the radiologist and clinical care team is critical to narrow down the differential and initiate correct management. WE is a reversible disease with catastrophic consequences if it is not recognized and treated promptly.

British Obesity and Metabolic Surgery Society Guidelines on perioperative and postoperative biochemical monitoring and micronutrient replacement for patients undergoing bariatric surgery-2020 update

Bariatric surgery is recognized as the most clinically and cost-effective treatment for people with severe and complex obesity. Many people presenting for surgery have pre-existing low vitamin and mineral concentrations. The incidence of these may increase after bariatric surgery as all procedures potentially cause clinically significant micronutrient deficiencies. Therefore, preparation for surgery and long-term nutritional monitoring and follow-up are essential components of bariatric surgical care. These guidelines update the 2014 British Obesity and Metabolic Surgery Society nutritional guidelines. Since the 2014 guidelines, the working group has been expanded to include healthcare professionals working in specialist and non-specialist care as well as patient representatives. In addition, in these updated guidelines, the current evidence has been systematically reviewed for adults and adolescents undergoing the following procedures: adjustable gastric band, sleeve gastrectomy, Roux-en-Y gastric bypass and biliopancreatic diversion/duodenal switch. Using methods based on Scottish Intercollegiate Guidelines Network methodology, the levels of evidence and recommendations have been graded. These guidelines are comprehensive, encompassing preoperative and postoperative biochemical monitoring, vitamin and mineral supplementation and correction of nutrition deficiencies before, and following bariatric surgery, and make recommendations for safe clinical practice in the U.K. setting.

Comparison between LigaSure™ and Harmonic® in Laparoscopic Sleeve Gastrectomy: A Single-Center Experience on 422 Patients

BACKGROUND

New laparoscopic devices, such as electrothermal bipolar-activated devices (LigaSure™ (LS)) or ultrasonic systems (Harmonic® scalpel (HS)), have been applied recently to bariatric surgery allowing to reduce blood loss and surgical risks. The aim of this study was to retrospectively compare intraoperative performance of HS and LS, postoperative results, and clinical outcomes in a large cohort of patients undergoing LSG.

METHODS

Data from 422 morbidly obese patients undergoing LSG in our Bariatric Unit at the Advanced Biomedical Sciences Department of the "Federico II" University of Naples (Italy) between January 2009 and December 2017 were retrospectively analyzed. Subjects were divided into two groups (HS and LS), and operative time, intraoperative complications, and postoperative (within 30 days from surgery) complications were compared. Bleeding from the omentum or from the staple line, use of hemostatic clips, and absorbable hemostat were recorded as intraoperative complications; hemorrhages, abscess formation, gastric leaks, fever, and mortality were considered as postoperative complications.

RESULTS

Statistical analysis showed no difference in terms of baseline demographics between the two cohorts. Operative time (48 ± 9 vs 49 ± 6 min, p=0.646) and the rates of intraoperative and postoperative complications did not significantly differ between groups.

CONCLUSION

Harmonic® and LigaSure™ are both useful tools in bariatric surgery, and these two advanced power devices are user-friendly and can facilitate surgeon work; from this point of view, the choice of the energy device should be based on the preference of the surgeon and on the hospital costs policy and availability.

Results following laparoscopic sleeve gastrectomy in elderly obese patients: a single center experience with follow-up at three years

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) represents the most performed bariatric surgical procedure worldwide. Morbid Overweight in elderly patients is becoming a significant health problem even in Italy. As well as in younger age groups, bariatric surgery could be indicated even in this subset of patients. However the advantages and results of LSG in patients over 60 years old have received minimal attention.

METHODS

The records of 375 patients underwent LSG between 2008 and 2016 were reviewed. In the entire series 18 patients were aged 60 years or older at the time of surgery. Since a 3 years follow-up was available for 12 patients out of the 18 aged over 60 we included in the study only these. General epidemiologic data, clinical findings, BMI and comorbidities surgical treatment and follow-up data were collected; postoperative measurements such as operative time, intraoperative complications, mortality rate, length of stay, incidence of early and late complications, Body mass Index (BMI), excess weight loss rate (EWL%) and comorbidities resolution were also recorded.

RESULTS

LSG was successfully performed for all geriatric patients. Global complications rate was 16.6% At 3 years mean BMI was 34.4±3.8 with a mean EWL% 66.1±31.9. Postoperative resolution of obesity comorbidities was observed; Hypertension (71.4%), type 2 Diabetes Mellitus (T2DM) (50.0%), obstructive sleep apnea syndrome (OSAS) (66.6%) respectively. No intraoperative complications or mortality were recorded.

CONCLUSIONS

LSG offered cure in geriatric patients affected by morbid obesity for weight loss and comorbidities resolution. Larger studies are necessary to analyze and minimize the incidence of postoperative complications associated to this surgical procedure in elderly patients.

Neurologic Manifestations of Vitamin B Deficiency after Bariatric Surgery

INTRODUCTION

The aim of this study was to assess the incidence, clinical presentation, and outcomes of neurologic disorders secondary to vitamin B deficiencies following bariatric surgery.

METHODS

Patients at a single academic institution who underwent bariatric surgery and developed neurologic complications secondary to low levels of vitamins B1, B2, B6, and B12 between the years 2004 and 2015 were studied.

RESULTS

In total, 47 (0.7%) bariatric surgical patients (Roux-en-Y gastric bypass n = 36, sleeve gastrectomy n = 9, and duodenal switch n = 2) developed neurologic manifestations secondary to vitamin B deficiencies. Eleven (23%) patients developed postoperative anatomical complications contributed to poor oral intake. Median duration to onset of neurologic manifestation following surgery was 12 months (IQR, 5-32). Vitamin deficiencies reported in the cohort included B1 (n = 30), B2 (n = 1), B6 (n = 12), and B12 (n = 12) deficiency. The most common manifestations were paresthesia (n = 31), muscle weakness (n = 15), abnormal gait (n = 11), and polyneuropathy (n = 7). Four patients were diagnosed with Wernicke-Korsakoff syndrome (WKS) which was developed after gastric bypass (n = 3) and sleeve gastrectomy (n = 1). Seven patients required readmission for management of severe vitamin B deficiencies. Overall, resolution of neurologic symptoms with nutritional interventions and pharmacotherapy was noted in 40 patients (85%). The WKS was not reversible, and all four patients had residual mild ataxia and nystagmus at the last follow-up time.

CONCLUSIONS

Nutritional neurologic disorders secondary to vitamin B deficiency are relatively uncommon after bariatric surgery. While neurologic disorders are reversible in most patients (85%) with vitamin replacements, persistent residual neurologic symptoms are common in patients with WKS.

An Autopsy Case of Misdiagnosed Wernicke's Syndrome after Intragastric Balloon Therapy

Intragastric balloon (IGB) therapy is a widely used technique to counter obesity, and it is known to be safe and effective. Although there can be a high rate of side effects following IGB therapy, most are self-healing and they are mainly accommodative in nature. Few cases of Wernicke's syndrome under IGB therapy have been described in the literature, and to the best of our knowledge, none have been fatal. We present here a case of a 51-year-old woman who underwent IGB therapy over 8 months. Late diagnosed Wernicke's syndrome that first appeared as lower limb neuropathy progressively immobilized the patient, until she required bed rest. Finally, a major complication of pneumonia caused her death. Wernicke's syndrome has been mainly related to bariatric surgery techniques, but it must also be linked to IGB therapy (and also to other restrictive weight-loss interventions). As the use of IGB therapy spreads, the literature must alert physicians to this complication. Wernicke's syndrome is a severe but reversible condition when diagnosed and treated early.

Case Report of Wernicke's Encephalopathy After Sleeve Gastrectomy

BACKGROUND

We report a case of a patient who was 3 months post-sleeve gastrectomy and presented with acute stroke symptoms ultimately due to Wernicke's encephalopathy (WE) after bariatric surgery. A 20-year-old white female presented to an outside hospital 3 months after sleeve gastrectomy complaining of nausea and vomiting. She initially underwent a cholecystectomy and later became less responsive and required intubation. Magnetic resonance imaging changes, presumed to be an acute stroke, prompted her transfer to our facility. Intravenous (IV) thiamin was administered, and the patient's symptoms improved over the course of her hospital stay.

RESULTS

Thiamin levels were markedly low, and the patient rapidly improved with the administration of IV thiamin. The patient was discharged to inpatient rehabilitation.

CONCLUSION

Bariatric surgery is a less common cause of WE but can lead to acute WE due to malabsorption of thiamin. In patients undergoing bariatric surgery, clinicians should be vigilant about the potential for WE to occur. In addition, based on history, WE should be considered in the differential diagnosis for symptoms of acute ischemic stroke.

Bariatric surgery and long-term nutritional issues

Bariatric surgery is recognized as a highly effective therapy for obesity since it accomplishes sustained weight loss, reduction of obesity-related comorbidities and mortality, and improvement of quality of life. Overall, bariatric surgery is associated with a 42% reduction of the cardiovascular risk and 30% reduction of all-cause mortality. This review focuses on some nutritional consequences that can occur in bariatric patients that could potentially hinder the clinical benefits of this therapeutic option. All bariatric procedures, to variable degrees, alter the anatomy and physiology of the gastrointestinal tract; this alteration makes these patients more susceptible to developing nutritional complications, namely, deficiencies of macro- and micro-nutrients, which could lead to disabling diseases such as anemia, osteoporosis, protein malnutrition. Of note is the evidence that most obese patients present a number of nutritional deficits already prior to surgery, the most important being vitamin D and iron deficiencies. This finding prompts the need for a complete nutritional assessment and, eventually, an adequate correction of pre-existing deficits before surgery. Another critical issue that follows bariatric surgery is post-operative weight regain, which is commonly associated with the relapse of obesity-related co-morbidities. Nu-tritional complications associated with bariatric surgery can be prevented by life-long nutritional monitoring with the administration of multi-vitamins and mineral supplements according to the patient's needs.

Fundus Findings in Wernicke Encephalopathy

Wernicke encephalopathy (WE) is an acute neuropsychiatric syndrome resulting from thiamine (vitamin B₁) deficiency, classically characterized by the triad of ophthalmoplegia, confusion, and ataxia. While commonly associated with chronic alcoholism, WE may also occur in the setting of poor nutrition or absorption. We present a 37-year-old woman who underwent laparoscopic sleeve gastrectomy and presented with visual disturbance with bilateral horizontal nystagmus, confusion, and postural imbalance. Fundus examination revealed bilateral optic disc edema with a retinal hemorrhage in the left eye. Metabolic workup demonstrated thiamine deficiency. Her symptoms resolved after thiamine treatment. This case raises the awareness of the possibility of posterior segment findings in WE, which are underreported in WE.

Severe Infections are Common in Thiamine Deficiency and May be Related to Cognitive Outcomes: A Cohort Study of 68 Patients With Wernicke-Korsakoff Syndrome

BACKGROUND

Wernicke encephalopathy can have different clinical outcomes. Although infections may precipitate the encephalopathy itself, it is unknown whether infections also modify the long-term outcome in patients developing Korsakoff syndrome.

OBJECTIVE

To determine whether markers of infection, such as white blood cell (WBC) counts and absolute neutrophil counts in the Wernicke phase, are associated with cognitive outcomes in the end-stage Korsakoff syndrome.

METHOD

Retrospective, descriptive study of patients admitted to Slingedael Korsakoff Center, Rotterdam, The Netherlands. Hospital discharge letters of patients with Wernicke encephalopathy were searched for relevant data on infections present upon hospital admission. Patients were selected for further analysis if data were available on WBC counts in the Wernicke phase and at least 1 of 6 predefined neuropsychological tests on follow-up.

RESULTS

Infections were reported in 35 of 68 patients during the acute phase of Wernicke-Korsakoff syndrome-meningitis (1), pneumonia (14), urinary tract infections (9), acute abdominal infections (4), sepsis (5) empyema, (1) and infection "of unknown origin" (4). The neuropsychological test results showed significant lower scores on the Cambridge Cognitive Examination nonmemory section with increasing white blood cell counts (Spearman rank correlation, ρ = -0.34; 95% CI: -0.57 to -0.06; 44 patients) and on the "key search test" of the behavioral assessment of the dysexecutive syndrome with increasing absolute neutrophil counts (ρ= -0.85; 95% CI: -0.97 to -0.42; 9 patients).

CONCLUSIONS

Infections may be the presenting manifestation of thiamine deficiency. Patients with Wernicke-Korsakoff syndrome who suffered from an infection during the acute phase are at risk of worse neuropsychological outcomes on follow-up.

Neurological Complications of Bariatric Surgery

Obesity has attained pandemic proportions, and bariatric surgery is increasingly being employed resulting in turn to more neurological complications which must be recognized and managed. Neurological complications may result from mechanical or inflammatory mechanisms but primarily result from micro-nutritional deficiencies. Vitamin B12, thiamine, and copper constitute the most frequent deficiencies. Neurological complications may occur at reasonably predictable times after bariatric surgery and are associated with the type of surgery used. During the early post-operative period, compressive or stretch peripheral nerve injury, rhabdomyolysis, Wernicke's encephalopathy, and inflammatory polyradiculoneuropathy may occur. Late complications ensue after months to years and include combined system degeneration (vitamin B12 deficiency) and hypocupric myelopathy. Bariatric surgery patients require careful nutritional follow-up with routine monitoring of micronutrients at 6 weeks and 3, 6, and 12 months post-operatively and then annually after surgery and multivitamin supplementation for life. Sustained vigilance for common and rare neurological complications is essential.

Lipid profile changes in patients undergoing bariatric surgery: a comparative study between sleeve gastrectomy and mini-gastric bypass

OBJECTIVE

To prospectively evaluate the effect of different types of bariatric surgery on lipid profile.

METHODS

Total cholesterol (TC), High-Density-Lipoprotein cholesterol (HDLc), Low-Density-Lipoprotein cholesterol (LDLc) and triglycerides (TG) levels were evaluated before surgery and at 3 different post-operative time-points (3, 6 and 12 months) in consecutive obese subjects undergoing mini-gastric bypass (MGB) or sleeve gastrectomy (SG).

RESULTS

At baseline, 74 MGB and 86 SG subjects were comparable for lipid profile and prevalence of hypercholesterolemia/hypertriglyceridemia. During the post-operative follow-up, both MGB and SG subjects showed significant changes in lipid profile. However, at 3 months, MGB patients showed higher changes in TC (β = 0.179, p = 0.022) and TG (β = 0.265, p = 0.001) than those undergoing SG. At 6-month post-operative follow-up, these differences were confirmed only for TC. After a 12-month follow-up, MGB and SG were entirely comparable for changes in lipid profile with the exception of HDLc, whose changes were higher in SG group (β = 0.130, p = 0.039). Overall, the probability to normalize lipid profile during the 12-month follow-up was similar in MGB and in SG patients (OR:1.24, 95%CI:0.41-3.76, p = 0.689).

CONCLUSION

Despites some differences at 3-6 post-operative months, during a 12-month follow-up, SG and MGB showed a similar efficacy in the improvement of lipid profile of obese patients.

Thiamin in Clinical Practice

Thiamin is a water-soluble vitamin also known as vitamin B1. Its biologically active form, thiamin pyrophosphate (TPP), is a cofactor in macronutrient metabolism. In addition to its coenzyme roles, TPP plays a role in nerve structure and function as well as brain metabolism. Signs and symptoms of thiamin deficiency (TD) include lactic acidosis, peripheral neuropathy, ataxia, and ocular changes (eg, nystagmus). More advanced symptoms include confabulation and memory loss and/or psychosis, resulting in Wernicke's encephalopathy and/or Wernicke's Korsakoff syndrome, respectively. The nutrition support clinician should be aware of patients who may be at risk for TD. Risk factors include those patients with malnutrition due to 1 or more nutrition-related etiologies: decreased nutrient intake, increased nutrient losses, or impaired nutrient absorption. Clinical scenarios such as unexplained heart failure or lactic acidosis, renal failure with dialysis, alcoholism, starvation, hyperemesis gravidarum, or bariatric surgery may increase the risk for TD. Patients who are critically ill and require nutrition support may also be at risk for TD, especially those who are given intravenous dextrose void of thiamin repletion. Furthermore, understanding thiamin's role as a potential therapeutic agent for diabetes, some inborn errors of metabolism, and neurodegenerative diseases warrants further research. This tutorial describes the absorption, digestion, and metabolism of thiamin. Issues pertaining to thiamin in clinical practice will be described, and evidence-based practice suggestions for the prevention and treatment of TD will be discussed.

Malnutrition-induced Wernicke's encephalopathy following a water-only fasting diet

BACKGROUND

Wernicke's encephalopathy is a critical condition of neurological dysfunction resulting from a deficiency in thiamine. Chronic alcoholism is recognized as the most common cause of Wernicke's encephalopathy, but other causes, including fasting/starvation and malnutrition, have been documented within the scientific literature. These causes may not be readily recognized by healthcare professionals and may lead to Wernicke's encephalopathy being overlooked as a diagnosis when a nonalcoholic patient presents with classic signs and symptoms of the disorder.

MATERIALS AND METHODS

A narrative review of thiamine and its relationship to the development, diagnosis, and treatment of Wernicke's encephalopathy is presented based on a review of evidence-based guidelines and published research. To heighten awareness of the development of Wernicke's encephalopathy in fasted/starved and malnourished patients and to contribute to the scientific body of knowledge for the identification and management of Wernicke's encephalopathy in these patients, the clinical course and treatment of an adult woman who developed Wernicke's encephalopathy following a 40-day water-only fasting diet is outlined.

RESULTS

Clinical suspicion was required to identify the patient's condition and initiate immediate intervention through parenteral thiamine administration. Oral thiamine supplementation of 100 to 800 mg per day for 6 months was required to aid recovery.

OUTCOMES

The patient's clinical course and response to treatment illustrate the necessity for clinical awareness and suspicion of Wernicke's encephalopathy among healthcare professionals, timely and adequate parenteral thiamine administration, and oral thiamine supplementation at therapeutic doses to correct the nutrient deficiency, halt the progression of Wernicke's encephalopathy, and promote recovery.

Haemostatic and fibrinolytic changes in obese subjects undergoing bariatric surgery: the effect of different surgical procedures

BACKGROUND

Little is known about effects of different bariatric surgery procedures on haemostatic and fibrinolytic parameters.

MATERIAL AND METHODS

Consecutive obese subjects undergoing gastric bypass (GBP) or sleeve gastrectomy (SG) were enrolled. In all patients, levels of haemostatic factors (FII, FVII, FVIII, FIX, FX, vWF, fibrinogen), fibrinolytic variables (PAI-1, t-PA and D-dimer) and natural anticoagulants (AT, protein C and protein S) were evaluated before and 2 months after surgery.

RESULTS

A total of 77 GBP and 79 SG subjects completed the study. At baseline no difference in coagulation parameters was found between the two groups. After both GBP and SG, subjects showed significant changes in haemostatic and fibrinolytic variables and in natural anticoagulant levels. The Δ% changes in FVII, FVIII, FIX, vWF, fibrinogen, D-dimer, protein C and protein S levels were significantly higher in subjects who underwent GBP than in those who underwent SG. Multivariate analysis confirmed that GBP was a predictor of higher Δ% changes in FVII (β=0.268, p=0.010), protein C (β=0.274, p=0.003) and protein S (β=0.297, p<0.001), but not in all the other variables. Following coagulation factor reduction, 31 subjects (25.9% of GBP and 13.9% of SG; p=0.044) showed overt FVII deficiency; protein C deficiency was reported by 34 subjects (32.5% of GBP vs 11.4% of SG, p=0.033) and protein S deficiency by 39 (37.6% of GBP vs 12.6% of SG, p=0.009). Multivariate analyses showed that GBP was associated with an increased risk of deficiency of FVII (OR: 3.64; 95% CI: 1.73-7.64, p=0.001), protein C (OR: 4.319; 95% CI: 1.33-13.9, p=0.015) and protein S (OR: 5.50; 95% CI: 1.71-17.7, p=0.004).

DISCUSSION

GBP is associated with an increased risk of post-operative deficiency in some vitamin K-dependent coagulation factors. Whereas such deficiency is too weak to cause bleeding, it is significant enough to increase the risk of thrombosis.

Thiamine and magnesium deficiencies: keys to disease

Thiamine deficiency (TD) is accepted as the cause of beriberi because of its action in the metabolism of simple carbohydrates, mainly as the rate limiting cofactor for the dehydrogenases of pyruvate and alpha-ketoglutarate, both being critical to the action of the citric acid cycle. Transketolase, dependent on thiamine and magnesium, occurs twice in the oxidative pentose pathway, important in production of reducing equivalents. Thiamine is also a cofactor in the dehydrogenase complex in the degradation of the branched chain amino acids, leucine, isoleucine and valine. In spite of these well accepted facts, the overall clinical effects of TD are still poorly understood. Because of the discovery of 2-hydroxyacyl-CoA lyase (HACL1) as the first peroxisomal enzyme in mammals found to be dependent on thiamine pyrophosphate (TPP) and the ability of thiamine to bind with prion protein, these factors should improve our clinical approach to TD. HACL1 has two important roles in alpha oxidation, the degradation of phytanic acid and shortening of 2-hydroxy long-chain fatty acids so that they can be degraded further by beta oxidation. The downstream effects of a lack of efficiency in this enzyme would be expected to be critical in normal brain metabolism. Although TD has been shown experimentally to produce reversible damage to mitochondria and there are many other causes of mitochondrial dysfunction, finding TD as the potential biochemical lesion would help in differential diagnosis. Stresses imposed by infection, head injury or inoculation can initiate intermittent cerebellar ataxia in thiamine deficiency/dependency. Medication or vaccine reactions appear to be more easily initiated in the more intelligent individuals when asymptomatic marginal malnutrition exists. Erythrocyte transketolase testing has shown that thiamine deficiency is widespread. It is hypothesized that the massive consumption of empty calories, particularly those derived from carbohydrate and fat, results in a high calorie/thiamine ratio as a major cause of disease. Because mild to moderate TD results in pseudo hypoxia in the limbic system and brainstem, emotional and stress reflexes of the autonomic nervous system are stimulated and exaggerated, producing symptoms often diagnosed as psychosomatic disease. If the biochemical lesion is recognized at this stage, the symptoms are easily reversible. If not, and the malnutrition continues, neurodegeneration follows and results in a variety of chronic brain diseases. Results from acceptance of the hypothesis could be tested by performing erythrocyte transketolase tests to pick out those with TD and supplementing the affected individuals with the appropriate dietary supplements.