Wernicke's encephalopathy: a more common disease than realised. A neuropathological study of 51 cases

Promising strategies for the prevention of alcohol-related brain damage through optimised management of acute alcohol withdrawal: A focussed literature review

There is an increasing awareness of the link between chronic alcohol consumption and the development of cognitive, behavioural and functional deficits. Currently, preventative strategies are limited and require engagement in dedicated long-term rehabilitation and sobriety services, the availability of which is low. The acute alcohol withdrawal syndrome is an episode of neurochemical imbalance leading to autonomic dysregulation, increased seizure risk and cognitive disorientation. In addition to harm from symptoms of alcohol withdrawal (e.g. seizures), the underpinning neurochemical changes may also lead to cytotoxicity through various cellular mechanisms, which long-term, may translate to some of the cognitive impairments observed in Alcohol-Related Brain Damage (ARBD). Here we review some of the pharmacological and neurochemical mechanisms underpinning alcohol withdrawal. We discuss the cellular and pharmacological basis of various potential neuroprotective strategies that warrant further exploration in clinical populations with a view to preventing the development of ARBD. Such strategies, when integrated into the clinical management of acute alcohol withdrawal, may impact large populations of individuals, who currently face limited dedicated service delivery and healthcare resource.

Observations on the Clinical Features of the Wernicke-Korsakoff Syndrome

This paper begins with a short case report of florid, spontaneous confabulation in a 61-year-old man with an alcohol-induced Wernicke-Korsakoff syndrome. His confabulation extended across episodic and personal semantic memory, as well as orientation in time and place, as measured on Dalla Barba's Confabulation Battery. Five other brief case summaries will then be presented, followed by a summary of the clinical, neurological, and background neuropsychological findings in three earlier series of Korsakoff patients. These observations will be considered in light of Wijnia's recent and my own, earlier reviews of the Korsakoff syndrome. Taken together, they indicate the need for a multi-faceted approach (clinical, neurological, neuropsychological, and neuroimaging) to the assessment and diagnosis of the disorder.

Alcohol use disorder: Neuroimaging evidence for accelerated aging of brain morphology and hypothesized contribution to age-related dementia

Excessive alcohol use curtails longevity by rendering intoxicated individuals vulnerable to heightened risk from accidents, violence, and alcohol poisoning, and makes chronically heavy drinkers vulnerable to acceleration of age-related medical and psychiatric conditions that can be life threatening (Yoon, Chen, Slater, Jung, & White, 2020). Thus, studies of factors influencing age-alcohol interactions must consider the potential that the alcohol use disorder (AUD) population may not represent the oldest ages of the unaffected population and may well have accrued comorbidities associated with both AUD and aging itself. Herein, we focus on the aging of the brains of men and women with AUD, keeping AUD contextual factors in mind. Knowledge of the potential influence of the AUD-associated co-factors on the condition of brain structure may lead to identifying modifiable risk factors to avert physical declines and may reverse or arrest further AUD-related degradation of the brain. In this narrative review, we 1) describe quantitative, controlled studies of brain macrostructure and microstructure of adults with AUD, 2) consider the possibility of recovery of brain integrity through harm reduction with sustained abstinence or reduced drinking, and 3) speculate on the ramifications of accelerated aging in AUD as contributing to age-related dementia.

Dysregulated balance in Th17/Treg axis of Pristane-induced lupus mouse model, are mesenchymal stem cells therapeutic?

BACKGROUND

Despite advances in general and targeted immunosuppressive therapies, limiting all mainstay treatment options in refractory systemic lupus erythematosus (SLE) cases has necessitated the development of new therapeutic strategies. Mesenchymal stem cells (MSCs) have recently emerged with unique properties, including a solid propensity to reduce inflammation, exert immunomodulatory effects, and repair injured tissues.

METHODS

An animal model of acquired SLE mice was induced via intraperitoneal immunization with Pristane and affirmed by measuring specific biomarkers. Bone marrow (BM) MSCs were isolated from healthy BALB/c mice and cultured in vitro, then were identified and confirmed by flow cytometry and cytodifferentiation. Systemic MSCs transplantation was performed and then several parameters were analyzed and compared, including specific cytokines (IL-17, IL-4, IFN-ɣ, TGF-β) at the serum level, the percentage of Th cell subsets (Treg/Th17, Th1/Th2) in splenocytes, and also the relief of lupus nephritis, respectively by enzyme-linked immunosorbent assay (ELISA), flow cytometry analysis and by hematoxylin & eosin staining and also immunofluorescence assessment. Experiments were carried out with different initiation treatment time points (early and late stages of disease). Analysis of variance (ANOVA) followed by post hoc Tukey's test was used for multiple comparisons.

RESULTS

The rate of proteinuria, anti-double-stranded deoxyribonucleic acid (anti-dsDNA) antibodies, and serum creatinine levels decreased with BM-MSCs transplantation. These results were associated with attenuated lupus renal pathology in terms of reducing IgG and C3 deposition and lymphocyte infiltration. Our findings suggested that TGF-β (associated with lupus microenvironment) can contribute to MSC-based immunotherapy by modulating the population of TCD4⁺ cell subsets. Obtained results indicated that MSCs-based cytotherapy could negatively affect the progression of induced SLE by recovering the function of Treg cells, suppressing Th1, Th2, and Th17 lymphocyte function, and downregulating their pro-inflammatory cytokines.

CONCLUSION

MSC-based immunotherapy showed a delayed effect on the progression of acquired SLE in a lupus microenvironment-dependent manner. Allogenic MSCs transplantation revealed the ability to re-establish the balance of Th17/Treg, Th1/Th2 and restore the plasma cytokines network in a pattern dependent on disease conditions. The conflicting results of early versus advanced therapy suggest that MSCs may produce different effects depending on when they are administered and their activation status.

Upregulation of TLR4/MyD88 pathway in alcohol-induced Wernicke’s encephalopathy: Findings in preclinical models and in a postmortem human case

Wernicke’s encephalopathy (WE) is a neurologic disease caused by vitamin B1 or thiamine deficiency (TD), being the alcohol use disorder its main risk factor. WE patients present limiting motor, cognitive, and emotional alterations related to a selective cerebral vulnerability. Neuroinflammation has been proposed to be one of the phenomena that contribute to brain damage. Our previous studies provide evidence for the involvement of the innate immune receptor Toll-like (TLR)4 in the inflammatory response induced in the frontal cortex and cerebellum in TD animal models (animals fed with TD diet [TDD] and receiving pyrithiamine). Nevertheless, the effects of the combination of chronic alcohol consumption and TD on TLR4 and their specific contribution to the pathogenesis of WE are currently unknown. In addition, no studies on TLR4 have been conducted on WE patients since brains from these patients are difficult to achieve. Here, we used rat models of chronic alcohol (CA; 9 months of forced consumption of 20% (w/v) alcohol), TD hit (TDD + daily 0.25 mg/kg i.p. pyrithiamine during 12 days), or combined treatment (CA + TDD) to check the activation of the proinflammatory TLR4/MyD88 pathway and related markers in the frontal cortex and the cerebellum. In addition, we characterized for the first time the TLR4 and its coreceptor MyD88 signature, along with other markers of this proinflammatory signaling such as phospo-NFκB p65 and IκBα, in the postmortem human frontal cortex and cerebellum (gray and white matter) of an alcohol-induced WE patient, comparing it with negative (no disease) and positive (aged brain with Alzheimer’s disease) control subjects for neuroinflammation. We found an increase in the cortical TLR4 and its adaptor molecule MyD88, together with an upregulation of the proinflammatory signaling molecules p-NF-ĸB and IĸBα in the CA + TDD animal model. In the patient diagnosed with alcohol-induced WE, we observed cortical and cerebellar upregulation of the TLR4/MyD88 pathway. Hence, our findings provide evidence, both in the animal model and the human postmortem brain, of the upregulation of the TLR4/MyD88 proinflammatory pathway in alcohol consumption–related WE.

Ameliorating effect of the biological Zinc nanoparticles in abamectin induced hepato-renal injury in a rat model: Implication of oxidative stress, biochemical markers and COX-2 signaling pathways

Extensive use of abamectin (ABM) as an anthelmintic in veterinary systems adversely affects the health and welfare of animals and humans. Zinc nanoparticles (ZnNPs) have therapeutic benefits and ameliorate the effect of environmental pollutants. In this study, we assessed the ameliorative effect of ZnNPs against the sub-lethal toxicity of ABM in rats. Forty healthy rats were randomly selected into four groups (n = 10); the control received normal saline and test rats were treated orally twice weekly with ABM (1 mg/kg bwt), ZnNPs (10 mg/kg bwt) and ABM + ZnNPs for 28 days. Upon completion of the study period, blood and tissue samples were collected and prepared for hematological, biochemical, pathological, and immunohistochemical analysis. Our results showed that ABM treatment significantly decreased body weight gain (BWG), red blood cells (RBCs), hemoglobin (Hb), hematocrit (HC), and platelet (PLT); while it significantly increased white blood cells (WBCs) and lymphocytes. ABM also significantly decreased antioxidant enzyme activities: superoxide dismuthase (SOD), glutathione peroxidase (GPx), and catalase (CAT) and increased hydrogen peroxide and malondialdehyde levels compared with other groups. ABM significantly raised alanine aminotransferase (ALT), aspartate amino transaminase (AST), and alkaline phosphatase (ALP) levels, which was restored by co-administration of ZnNPs. Moreover, ZnNPs ameliorated ABM-mediated negative histopathological changes in the liver and kidney tissues, exhibiting a significant protective effect. Cyclooxygenase 2 (COX-2) + immuno-expression were reduced after pretreatment with ZnNPs. These findings suggested that co-administration of ZnNPs with ABM mitigated its toxicity by combating oxidative stress and boosting antioxidant capacity, indicating the efficacy of ZnNPs in attenuating ABM toxicity.

Early treatment with thiamine and mortality among patients with alcohol use disorder who are hospitalized for pneumonia

BACKGROUND

The paucity of research linking thiamine treatment with improved outcomes may be driving its underutilization among patients at risk for Wernicke encephalopathy.

OBJECTIVE

To assess relationships of thiamine usage to outcomes of patients hospitalized with alcohol use disorder and pneumonia. DESIGN, SETTING AND PARTICIPANTS: This is a retrospective cohort study of adult patients hospitalized with pneumonia who also have alcohol use disorder and were treated with benzodiazepines during the initial two hospital days, between 2010 and 2015 at hospitals participating in the Premier Healthcare Database.

EXPOSURE

Any thiamine treatment, and, among those treated, high-dose thiamine treatment, during the initial two hospital days.

MAIN OUTCOME AND MEASURES

Death on days 3-14 of hospitalization (primary); discharge home; transfer to intensive care unit; length of stay (LOS). We used propensity-weighted models to estimate treatment effects.

RESULTS

Among 36,732 patients from 625 hospitals, 26,520 (72.2%) patients received thiamine, with mortality of 6.5% and 8.1% among recipients and nonrecipients, respectively. With propensity score adjustment, thiamine was associated with reduced mortality (odds ratio [OR]: 0.80, 95% confidence interval [CI]: 0.75-0.85) and more frequent discharges to home (OR: 1.10, 95% CI: 1.06-1.14). Other outcomes were similar. Relative to low-dose thiamine, high-dose thiamine was not associated with mortality (adjusted OR: 0.99, 95% CI: 0.89-1.10), but LOS was longer (ratio of means: 1.06, 95% CI: 1.04-1.08), and discharges to home were less frequent (OR: 0.92, 95% CI: 0.87-0.97).

CONCLUSION

Thiamine is not reliably given to patients with pneumonia and alcohol use disorder receiving benzodiazepines. Improving thiamine administration may represent an opportunity to save lives in this high-risk group of inpatients.

What is the Korsakoff syndrome? - a paper in tribute to Prof Alwyn Lishman

INTRODUCTION

Alwyn Lishman was interested in how memory research could be applied to clinical psychiatry. After a brief review of his major contributions, this paper will focus on his research on the alcoholic Korsakoff syndrome. It will consider how his findings relate to contemporary debates, particularly on how the syndrome should be defined, and its relationship to broader alcohol-induced cognitive impairments.

METHODS

A review of the contribution of Alwyn Lishman, Robin Jacobson and colleagues to our knowledge of Korsakoff's syndrome, together with a review of the pertinent recent literature.

RESULTS

Lishman and colleagues followed earlier authors in defining the Korsakoff syndrome in terms of disproportionate memory impairment, but they also noted a variable degree of IQ, frontal-executive, and timed visuo-spatial impairment in their cases. More recent authors have included such features in their definitions of the syndrome. Lishman also argued for a specific "alcoholic dementia". The present paper argues that recent definitions of the Korsakoff syndrome confound its core and associated features, and also fail to recognise the multifactorial basis of alcohol-related brain damage.

CONCLUSIONS

Korsakoff's syndrome is best defined in terms of disproportionate memory impairment, and more widespread cognitive impairment is best encompassed within "alcohol-related brain damage".

Low rates of thiamine prescribing in adult patients with alcohol-related diagnoses in the emergency department

Background: Alcohol use disorder (AUD) is associated with thiamine deficiency and Wernicke-Korsakoff Syndrome (WKS). Thiamine supplementation for the prevention of WKS in patients with suspected AUD in the Emergency Department (ED) is generally recommended. As alcohol-related diagnoses are frequent reasons for visits to EDs, ED thiamine prescribing practices are relevant to the overall management and prevention of WKS in patients with AUD.Objective: To determine the prescription rates of thiamine to patients with alcohol-related diagnoses in the ED.Methods: This was a retrospective chart review conducted at two New York City urban teaching hospitals from January 1 to December 31, 2017. All patients 18 years or older who were given an alcohol-related diagnosis (all F10 ICD-10-CM codes) upon disposition were included. Collected data included details of thiamine prescribing practices, patient demographics and patient disposition.Results: A total of 7,529 patient visits with an alcohol-related diagnosis were identified. The overall median age of included patients was 44; 5747 (76.3%) patient visits were by men; 310 (4.1%) patient visits resulted in admission. Out of all patient visits, thiamine was ordered during 167 (2.2%) visits, with thiamine administered parenterally during 129 (77.2%) visits and orally in 38 (22.8%) visits. Out of patient visits specifically associated with an F10.2 (Alcohol Dependence) diagnosis, thiamine was ordered during 105 (17.8%) visits.Conclusion: We found a very low rate of thiamine prescribing during patient visits associated with alcohol-related diagnoses. This may be a missed opportunity to reduce morbidity and mortality among AUD ED patients.

Ephedra sinica mitigates hepatic oxidative stress and inflammation via suppressing the TLR4/MyD88/NF-κB pathway in fipronil-treated rats

Ephedra sinica (ES) is a promising medicinal plant with a wide range of pharmacological aspects, including antioxidant and anti-inflammatory properties. Fipronil (FN) is a popularly used systemic insecticide in agriculture and veterinary applications. FN exposure can result in a variety of negative health consequences. The study aimed to explore the prophylactic effects of Ephedra sinica extract (ESE) against hepatotoxicity in FN-treated rats by following the TLR4/ MyD88/ NF-κB pathway. ESE was tested for polyphenolic and antioxidant activity. Forty rats were separated into four groups and given orally by FN (10 mg/kg B.W.) and/or ESE (150 mg/kg B.W.). Blood and tissue samples were collected at the end of the experiment and prepared for pathophysiological, gene expression, and pathological analysis. ESE showed strong antioxidant activity, as well as reduced levels of hepatic MDA and oxidative stress markers (H₂O₂, NO). Hepatic SOD and CAT activities were increased even further. Furthermore, in FN-treated rats, ESE improved liver functions (ALT, AST, ALP, and LDH) and recovered the lipid profile (Cho, TriG, HDL, and LDL). Moreover, by inhibiting TLR4/ MyD88/ NF-κB induction, ESE alleviated hepatic pathological changes and decreased FN-induced elevations of TNF-α, IL-6, and IL-1β mRNA/protein levels. These findings suggested that ESE mitigated FN-induced hepatotoxicity via combating oxidative stress and relieving inflammation.

Thiamine and diabetes: back to the future?

The first reports of a link between thiamine and diabetes date back to the 1940s. Some years later, a role for thiamine deficiency in diabetic neuropathy became evident, and some pilot studies evaluated the putative effects of thiamine supplementation. However, the administration of thiamine and its lipophilic derivative benfotiamine for the treatment of this complication gained consensus only at the end of the '90 s. The first evidence of the beneficial effects of thiamine on microvascular cells involved in diabetic complications dates to 1996: from then on, several papers based on in vitro and animal models have addressed the potential use of this vitamin in counteracting diabetic microangiopathy. A few pilot studies in humans reported beneficial effects of thiamine administration on diabetic nephropathy, but, despite all promising proofs-of-concept, the possible role of thiamine in counteracting development or progression of retinopathy has not been addressed until now. Thiamine is a water-soluble vitamin, rapidly expelled from the body, with no issues of over-dosage or accumulation; unfortunately, it is non-patentable, and neither industry nor independent donors are interested in investing in large-scale randomized controlled clinical trials to investigate its potential in diabetes and its complications. Consequently, science will not be able to disprove a promising hypothesis and, more importantly, diabetic people remain deprived of a possible way to ameliorate their condition.

A randomized double-blind placebo-controlled trial of intravenous thiamine for prevention of delirium following allogeneic hematopoietic stem cell transplantation

OBJECTIVE

To determine if high dose intravenous (IV) thiamine can prevent delirium during hospitalization following allogeneic HSCT. Secondarily, we evaluated the effects of high dose IV thiamine on thiamine levels and explored risk factors for delirium.

METHODS

Randomized, double-blind, placebo-controlled trial in patients undergoing allogeneic HSCT at a U.S. academic medical center between October 2017 and March 2020. 64 participants were randomized 1:1 to thiamine 200 mg IV three times daily for 7 days or placebo. We used the Delirium Rating Scale to assess for delirium. Delirium incidence was compared between groups using the chi-square test. Group differences in time to onset and duration of delirium were compared using the Kaplan-Meier method. Fisher's Exact and Wilcoxon Rank Sum tests were used to examine associations between pre-transplantation variables and delirium.

RESULTS

61 participants were analyzed. Delirium incidence (25% vs. 21%, Chi-square (df = 1) = 0.12, p = 0.73), time to onset, duration, and severity were not different between study arms. Immediately following the intervention, thiamine levels were higher in the thiamine arm (275 vs. 73 nmol/L, t-test (df = 57) = 13.63, p < 0.0001), but not predictive of delirium. Variables associated with delirium in our sample included disease severity, corticosteroid exposure, infection, and pre-transplantation markers of nutrition.

CONCLUSION

High dose IV thiamine did not prevent delirium in patients receiving allogeneic HSCT. Given the multiple contributors to delirium in this population, further research regarding the efficacy of multicomponent interventions may be needed.

TRIAL REGISTRATION

Clinical Trials NCT03263442.

FUNDING

Rising Tide Foundation for Clinical Cancer Research.

Design of a randomized placebo controlled trial of high dose intravenous thiamine for the prevention of delirium in allogeneic hematopoietic stem cell transplantation

BACKGROUND

Delirium is a highly prevalent and preventable neuropsychiatric condition with major health consequences. Thiamine deficiency is a well-established cause of delirium in those with chronic, severe alcoholism, but there remains an underappreciation of its significance in non-alcoholic populations, including patients with cancer. Treatment of suspected thiamine-related mental status changes with high dose intravenous (IV) thiamine has preliminary evidence for improving a variety of cognitive symptoms in oncology inpatient settings but has never been studied for the prevention of delirium in any population.

OBJECTIVES

The primary objective of this clinical trial is to determine if high dose IV thiamine can prevent delirium in patients receiving allogeneic hematopoietic stem cell transplantation (HSCT) for treatment of cancer. Secondary objectives are to determine if thiamine status is predictive of delirium onset and if high dose IV thiamine can attenuate the deleterious impact of delirium on health-related quality of life (HRQOL), functional status, and long-term neuropsychiatric outcomes.

METHODS

In this phase II study, we are recruiting 60 patients undergoing allogeneic HSCT, randomizing them to treatment with high dose IV thiamine (n = 30) versus placebo (n = 30), and systematically evaluating all participants for delirium and related comorbidities. We use the Delirium Rating Scale to measure the severity and duration of delirium during hospitalization for HSCT. We obtain thiamine levels weekly during the transplantation hospitalization. We assess HRQOL, functional status, depression, post-traumatic stress symptoms, and cognitive function prior to and at one, three, and six months after transplantation.

Prevalence of Low Plasma Vitamin B1 in the Stroke Population Admitted to Acute Inpatient Rehabilitation

OBJECTIVE

To determine the prevalence of vitamin B1 (VitB1) deficiency in the stroke population admitted to acute inpatient rehabilitation.

DESIGN

Retrospective cohort study.

SETTING

Acute inpatient rehabilitation facility at an academic medical center.

PARTICIPANTS

119 consecutive stroke patients admitted to stroke service from 1 January 2018 to 31 December 2018.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Plasma VitB1 level.

RESULTS

There were 17 patients (14%; 95% CI 9-22%) with low VitB1 with a range of 2-3 nmol/L, an additional 58 (49%; CI 40-58%) patients had normal low VitB1 with a range of 4-9 nmol/L, twenty-five patients (21%; CI 15-29%) had normal high VitB1 with a range of 10-15 nmol/L, and nineteen patients (16%; CI 10-24%) had high VitB1 with a range of 16-43 nmol/L.

CONCLUSIONS

In this cohort of patients admitted to the stroke service at an acute rehabilitation facility, there is evidence of thiamine deficiency. Moreover, the data suggest that there is inadequate acute intake of VitB1. Given the role of thiamine deficiency in neurologic function, further study of the role of thiamine optimization in the acute stroke rehabilitation population is warranted.

Improving thiamine prescribing at an academic hospital network using the computerized provider order entry system: a cohort study

BACKGROUND

Oral thiamine therapy is frequently prescribed to patients at risk for thiamine deficiency despite recommendations emphasizing the need for high doses of parenteral thiamine to reverse brain thiamine deficits. We evaluated the effect of changes to the computerized provider order entry system on the proportion of prescriptions for parenteral thiamine treatment (primary outcome) and dosages prescribed (secondary outcome) within our academic hospital network.

METHODS

We obtained data from the pharmacy information system recording thiamine prescribed to inpatients at University Health Network hospitals (Toronto, Ontario) before (Jan. 1, 2010, to Dec. 31, 2011) and after (Nov. 21, 2013, to Apr. 30, 2017) changes to the computerized provider order entry system promoting the use of higher dosages (≥ 200 mg) of parenterally administered thiamine. Patients receiving thiamine as part of total parenteral nutrition were excluded from analyses, as thiamine prescribing was automated and unlikely to be affected by the intervention.

RESULTS

A total of 6105 thiamine prescriptions were written for 2907 patients before the intervention and 12 787 thiamine prescriptions for 8032 patients after the intervention. The proportion of prescriptions for parenteral treatment increased from 55.5% (3386/6105) to 92.5% (11 829/12 787) after the intervention (p < 0.001). Increases in prescribing of parenteral thiamine treatment were sustained or enhanced across the 3.4-year observation period and were realized across all hospital services. Prescriptions for higher dosages of thiamine increased from 1.1% (65/6105) to 61.4% (7845/12 787) after the intervention (p < 0.001).

INTERPRETATION

Changes to the computerized provider order entry system were associated with sustained increases in the proportion of prescriptions for high-dose parenteral thiamine therapy. Similar approaches may be leveraged to align prescriber behaviour with well-accepted practice parameters in other areas of medicine.

Wernicke's Encephalopathy due to Non-Alcoholic Gastrointestinal Tract Disease

Introduction

Wernicke's encephalopathy (WE) is an underdiagnosed neuropsychiatric disorder especially in non-alcoholic groups that causes morbidity-mortality if diagnosis is delayed. Korsakoff syndrome is a chronic consequence of this condition characterized by persistent memory impairment. In this study we present a series of non-alcoholic patients with WE. The purpose of this study was to analyze the predisposing factors in non-alcoholic patients with WE and emphasize the importance of early diagnosis and treatment with thiamine supplementation.

Methods

The clinical records of 6 cases with WE followed by gastrointestinal tract disease and/or surgery who were admitted to our Medical Faculty between 2012 and 2014 were retrospectively reviewed.

Results

The study included 3 men and 3 women in the age range of 24 to 55. All patients had gastrointestinal tract diseases and/or had undergone gastrointestinal surgeries, and were non-alcoholic. Vomiting, weight loss, and parenteral nutrition were the frequent precipitating factors. The classic triad of mental impairment, oculomotor alterations and gait ataxia was present in 4 of the 6 patients. Magnetic Resonance Imaging showed typical signal alterations in the medial thalami, mammillary bodies and the periaqueductal region of patients in various degrees. Clinical improvement was seen in each patient after thiamine supplementation.

Discussion

Physicians should be aware of the predisposing factors and symptoms to prevent or optimize the management of this potentially devastating disease. Thiamine supplementation should be considered in patients with gastrointestinal tract diseases or those who have undergone surgery.

Hepatoprotective activity of Uncaria tomentosa extract against sub-chronic exposure to fipronil in male rats

The effects of fipronil (FPN) on the liver of rats were studied. Rats (n = 6) were treated with 9.7 mg/kg (1/10 of FPN LD₅₀), and other rats (n = 6) received 120 mg/kg of 10% Uncaria tomentosa extract, while a mixture of 9.7 mg/kg FPN and 120 mg/kg of 10% Uncaria tomentosa extract were administered orally to the rats (n = 6) daily for 6 weeks. Body, hepatic weights, liver enzymes, and lipid profile were determined. Hepatic activities of MDA, TNO, TAC, TNF-α, and IL-6 in liver homogenate were measured. Immunohistochemistry of NF-kB and liver histopathology were performed. Fipronil-treated rats had a significant (P = 0.02) lower weight gain. Moreover, relative liver weight was significantly (P = 0.003) increased in FPN-treated rats. Rats administrated with FPN exhibited a significantly (P = 0.02) higher liver enzymes and promoted levels of MDA, TNO, TNF-α, and IL-6 (P < 0.0001) than that in the other groups. Immunostaining of NF-κB was increased (P < 0.0001) in FPN-treated rats. Interestingly, Uncaria tomentosa alone or with FPN decreased the liver immunostaining of NF-κB. In conclusion, FPN produced liver injury through lipid peroxidation and stimulation of NF-κB. However, Uncaria tomentosa combated the oxidative stress and liver damage induced by FPN via inhibition of NF-κB.

An autopsied case of MM1-type sporadic Creutzfeldt-Jakob disease with pathology of Wernicke encephalopathy

An 83-year-old Japanese man presented with gait disturbance followed by rapidly-progressive cognitive impairment. Magnetic resonance diffusion-weighted images showed extensive hyperintense regions in the cerebral cortex. Four weeks after symptom onset, myoclonus appeared, and the patient developed difficulty swallowing; intravenous peripheral continuous infusions without vitamin supplementation were administered during the last two months of the patient’s life. The patient reached the akinetic mutism state and died 12 weeks after symptom onset due to sepsis. The brain weighed 940 g and showed general cerebral atrophy. Extensive spongiform change were observed in the cerebral cortex, striatum, thalamus, and cerebellar cortex, but gliosis was generally mild. Numerous newly-developed hemorrhage foci were observed in the mammillary body, the areas adjacent to the third and fourth ventricles, and the periaqueduct of the midbrain; however, proliferation of capillaries and endothelium and collections of macrophages were relatively inconspicuous. These findings suggested comorbidity with the acute stage of Wernicke encephalopathy (WE). Immunostaining showed extensive diffuse synaptic-type prion protein deposition in the gray matter. According to the neuropathological, genetic, and molecular findings, the present case was finally diagnosed as MM1-type sporadic Creutzfeldt-Jakob disease (CJD) with WE. We should remain alert to the diagnosis of WE when CJD is suspected, and it is necessary to consider the complications of both diseases. This report emphasizes the importance of pathological investigations for the diagnosis of CJD, WE, and the coexistence of both.

Thiamine Prescribing and Wernicke's Encephalopathy Risk Factors in Patients With Alcohol Use Disorders at a Psychiatric Hospital

BACKGROUND

Alcohol use disorder (AUD) is the leading cause of thiamine deficiency and can lead to Wernicke's encephalopathy (WE). WE has a higher prevalence of development in patients with AUD, and current recommendations emphasize parenteral administration of thiamine. Our objective was to characterize thiamine utilization in patients with AUD who were prescribed thiamine and evaluate if those who received oral thiamine had risk factors for the development of WE.

METHODS

This retrospective chart review enrolled adults admitted to a psychiatric hospital from October 2014 through September 2015 diagnosed with AUD as per the International Classification of Diseases, Ninth Edition (ICD-9). The cohort was divided on the basis of route of thiamine administration (nonparenteral vs. parenteral) and was then screened retrospectively for risk factors for WE. Descriptive data and measures of central tendency were utilized to assess the objectives.

RESULTS

The majority of patients were white male individuals, with a mean age of 48 years. Of the 226 patients, 201 (89%) were prescribed oral thiamine. Of the first 100 patients who received oral thiamine, 36% had risk factors for WE, with the most common risk factor being malnutrition. A χ analysis revealed that WE risk factors did not influence route of thiamine administration (χ=2.148, df=1, P=0.143). No patients were diagnosed with WE during their admission; however, 8 patients received parenteral thiamine at a treatment dose indicated for WE.

CONCLUSIONS

Parenteral thiamine is underutilized in patients with AUD and risk factors for WE. Education is needed to enhance thiamine prescribing and evaluation of risk factors for WE in this population. A thiamine prescribing protocol has been developed for further thiamine optimization.

Early detection and successful treatment of Wernicke's encephalopathy in outpatients without the complete classic triad of symptoms who attended a psycho-oncology clinic

Objective

Wernicke's encephalopathy (WE) is a neuropsychiatric disorder caused by a thiamine deficiency. Although WE has been recognized in cancer patients, it can be overlooked because many patients do not exhibit symptoms that are typical of WE, such as delirium, ataxia, or ocular palsy. Furthermore, outpatients with WE who intermittently present at psycho-oncology clinics have not been described as far as we can ascertain.

Method

This report describes two patients who did not exhibit the complete classic triad of symptoms among a series with cancer and WE, and who attended a psycho-oncology outpatient clinic.

Result

Case 1, a 76-year-old woman with pancreatic cancer and liver metastasis, periodically attended a psycho-oncology outpatient clinic. She presented with delirium and ataxia as well as appetite loss that had persisted for 8 weeks. We suspected WE, which was confirmed by low serum thiamine levels and the disappearance of delirium after thiamine administration. Case 2, a 79-year-old man with advanced stomach cancer, was referred to a psycho-oncology outpatient clinic with depression that had persisted for about 1 month. He also had appetite loss that had persisted for several weeks. He became delirious during the first visit to the outpatient clinic. Our initial suspicion of WE was confirmed by low serum thiamine levels and the disappearance of delirium after thiamine administration. The key indicator of a diagnosis of WE in both patients was appetite loss.

Significance of results

This report emphasizes awareness of WE in the outpatient setting, even when patients do not exhibit the classical triad of WE. Appetite loss might be the key to a diagnosis of WE in the absence of other causes of delirium.

Clinical Characteristics and Outcomes Associated With High-Dose Intravenous Thiamine Administration in Patients With Encephalopathy

BACKGROUND

Wernicke encephalopathy is a common neuropsychiatric syndrome due to thiamine deficiency. There is no consensus regarding thiamine dosing when Wernicke encephalopathy is suspected. A longstanding dosing strategy for Wernicke encephalopathy is 100mg daily, yet updated clinical guidelines suggest using high-dose intravenous (HDIV) thiamine.

OBJECTIVE

To describe thiamine prescribing practices at a large, public academic hospital and investigate clinical characteristics and outcomes associated with HDIV thiamine in patients with encephalopathy who received IV thiamine.

METHODS

Electronic medical records of hospitalized patients who received thiamine between 4/4/2014 and 11/1/2015 were reviewed. Chi-square tests, Wilcoxon Rank Sum tests, and logistic regression were used to compare clinical variables in patients with encephalopathy who received HDIV thiamine (≥ 200mg twice daily) vs lower doses of IV thiamine.

RESULTS

Among the total of 5236 thiamine orders, 29% (n = 1531) were IV; 10% (n = 150) of IV orders met HDIV criteria. In patients with encephalopathy who received IV thiamine (n = 432), HDIV thiamine was administered to 20% (n = 86) and only 2.1% (n = 9) received dosing consistent with Royal College of Physicians guidelines. In bivariable analyses, HDIV thiamine was associated with surgical services (p = 0.001), psychiatric consultation (p < 0.001), and decreased mortality (p = 0.004). In multivariable models, the association between HDIV thiamine and decreased in-hospital mortality did not meet statistical significance (p = 0.061).

CONCLUSIONS

In a large, public academic hospital, guideline-concordant thiamine supplementation is rare and HDIV thiamine is infrequently prescribed to patients with encephalopathy. Further studies are needed to confirm the possible benefits of HDIV thiamine for patients with suspected thiamine-deficient encephalopathy.

Pharmacy-based intervention in Wernicke's encephalopathy

Aims and method

Clinical audit methodology was used to compare the treatment of alcohol misusers at risk of Wernicke's encephalopathy in an acute medical setting, and to assess the impact of providing information about best practice to prescribing doctors. All patients prescribed thiamine during an admission to an acute hospital trust over a 6-month period were identified, and data about their treatment episode were collected retrospectively. Hospital pharmacists then provided all prescribers with a flowchart summarising current prescribing guidelines, and prescribing patterns were re-audited 6 months later.

Results

Over two audit periods, half of the patients prescribed thiamine whose case notes we examined had symptoms suggestive of Wernicke's encephalopathy, and another 30% were at high risk. Prescribing adhered to hospital guidelines only in 14% of cases, with the pharmacy-led intervention associated with a small but significant increase in the number of patients receiving adequate treatment for Wernicke's encephalopathy.

Clinical implications

Wernicke's encephalopathy is relatively common in alcohol-dependent individuals admitted to hospital, and it is easily and cheaply managed. However, even when potential cases are identified, prescribing guidelines are followed in a minority of cases, even with prompting by a hospital pharmacist. This may be related to the limited research base concerning the optimum dosing schedule of thiamine, or fears about possible anaphylaxis when using parenteral preparations.

Contributions to Understanding the Neuropsychology of Alcoholism: An INS Legacy

Alcohol use disorder (AUD) has been a major cause of family, social, and personal strife for centuries, with current prevalence estimates of 14% for 12-month and 29% lifetime AUD. Neuropsychological testing of selective cognitive, sensory, and motor functions complemented with in vivo brain imaging has enabled tracking the consequences of AUD, which follows a dynamic course of development, maintenance, and recovery or relapse. Controlled studies of alcoholism reviewed herein provide evidence for disruption of selective functions involving executive, visuospatial, mnemonic, emotional, and attentional processes, response inhibition, prosody, and postural stability and brain systems supporting these functions. On a hopeful front, longitudinal study provides convincing evidence for improvement in brain structure and function following sustained sobriety. These discoveries have a strong legacy in the International Neuropsychological Society (INS), starting from its early days when assumptions regarding which brain regions were disrupted relied solely on patterns of functional sparing and impairment deduced from testing. This review is based on the symposium presentation delivered at the 2017 annual North American meeting of the INS in celebration of the 50th anniversary since its institution in 1967. In the spirit of the meeting's theme, "Binding the Past and Present," the lecture and this review recognized the past by focusing on early, rigorous neuropsychological studies of alcoholism and their influence on research currently conducted using imaging methods enabling hypothesis testing of brain substrates of observed functional deficits. (JINS, 2017, 23, 843-859).

Thiamine Prescribing Practices for Adult Patients Admitted to an Internal Medicine Service

BACKGROUND

Thiamine (vitamin B₁) is an essential cofactor responsible for the breakdown of glucose, and its deficiency is associated with Wernicke encephalopathy (WE). There is a lack of evidence from systematic studies on the optimal dosing of thiamine for WE. Objectives: The primary objective was to describe the prescribing patterns for IV thiamine in adult patients admitted to a large teaching hospital. The secondary objective was to evaluate the clinical resolution of WE symptoms (confusion, ataxia, and/or ocular motor abnormalities) in relation to the dose of IV thiamine prescribed.

METHODS

A retrospective design was used to review data for adult patients admitted to an internal medicine service from June 1, 2014, to June 30, 2015. All patients included in the study received IV thiamine: low-dose therapy was defined as 100 mg IV daily and high-dose therapy was defined as dosage greater than 100 mg IV daily.

RESULTS

A total of 141 patients were included; low-dose thiamine was prescribed for 115 (81.6%) and high-dose thiamine for 26 (18.4%). Patients for whom high-dose thiamine was prescribed were more likely to be those in whom a diagnosis of WE was being considered (12/26 [46.2%] versus 5/115 [4.3%], p < 0.001). Of the total 219 IV thiamine doses ordered, 180 (82.2%) were for 100 mg, and 143 (65.3%) were prescribed for once-daily administration. There was no statistically significant difference in the time to resolution of WE symptoms for patients receiving high-dose versus low-dose thiamine.

CONCLUSIONS

A wide variety of thiamine prescribing patterns were noted. This study did not show a difference in time to resolution of WE symptoms in relation to the dose of IV thiamine. Additional large-scale studies are required to determine the optimal dosing of thiamine for WE.

Long-Term Mortality of Patients with an Alcohol-Related Wernicke–Korsakoff Syndrome

Aims

To characterize a series of contemporary patients with alcohol-related Wernicke's encephalopathy (WE) or Korsakoff's syndrome (KS) and to update the current prognosis of disease.

Methods

Retrospective and prospective study of patients diagnosed with an alcohol-related WE or KS between 2002 and 2011 in a tertiary hospital. Socio-demographic, alcohol use characteristics, signs and symptoms, co-morbidity and blood parameters were obtained at admission. Patients were followed up until 2013 and causes of death were ascertained through the review of charts.

Results

Sixty-one patients were included (51 with WE and 10 with KS). Among patients with WE, 78% were men and age at diagnosis was 57 years (interquartile range (IQR): 49–66). Twenty-three percent fulfilled the classic WE triad. Regarding Caine's criteria for WE, 70.6% presented with at least two out of four signs or symptoms. Median follow-up of patients with WE syndrome was 5.3 years (IQR: 2.6–8.8), the cumulated mortality was 45% and death rate of 7.4 × 100 person-years (95% confidence interval (CI): 4.8–10.9). Overall, 50% of patients would be expected to die within 8 years of WE episode and main causes of death included serious bacterial infections (44.5%) and cancer (33.3%).

Conclusions

Survival of patients with an alcohol-related Wernicke–Korsakoff syndrome is poor; pursuing treatment of alcohol use disorder and early diagnosis of thiamine deficiency is a priority for improving clinical outcomes.

The emergency medicine management of severe alcohol withdrawal

INTRODUCTION

Alcohol use is widespread, and withdrawal symptoms are common after decreased alcohol intake. Severe alcohol withdrawal may manifest with delirium tremens, and new therapies may assist in management of this life-threatening condition.

OBJECTIVE

To provide an evidence-based review of the emergency medicine management of alcohol withdrawal and delirium tremens.

DISCUSSION

The underlying pathophysiology of alcohol withdrawal syndrome (AWS) is central nervous system hyperexcitation. Stages of withdrawal include initial withdrawal symptoms, hallucinations, seizures, and delirium tremens. Management focuses on early diagnosis, resuscitation, and providing medications with gamma-aminobutyric acid (GABA) receptor activity. Benzodiazepines with symptom-triggered therapy have been the predominant medication class utilized and should remain the first treatment option with rapid escalation of dosing. Treatment resistant withdrawal warrants the use of phenobarbital or propofol, both demonstrating efficacy in management. Propofol can be used as an induction agent to decrease the effects of withdrawal. Dexmedetomidine does not address the underlying pathophysiology but may reduce the need for intubation. Ketamine requires further study. Overall, benzodiazepines remain the cornerstone of treatment. Outpatient management of patients with minimal symptoms is possible.

CONCLUSIONS

Alcohol withdrawal syndrome can result in significant morbidity and mortality. Physicians must rapidly diagnose these conditions while evaluating for other diseases. Benzodiazepines are the predominant medication class utilized, with adjunctive treatments including propofol or phenobarbital in patients with withdrawal resistant to benzodiazepines. Dexmedetomidine and ketamine require further study.

Hepatoprotective Efficacy of Cichorium intybus L. Extract Against Carbon Tetrachloride-induced Liver Damage in Rats

The purpose of the study was to assess the phytochemical and hepatoprotective activity of different extracts of dried herb of Cichorium intybus L. against carbon tetrachloride (CCl4) intoxicated male albino rats. The hepatoprotective activity of different extracts at 500 mg/kg body weight was compared with carbon tetrachloride-treated animals. The animals were divided into five groups with six animals in each group. The first group represents control, the second group received carbon tetrachloride, the third received C. intybus, and the fourth group received C. intybus plus carbon tetrachloride. The fifth group received silymarin as hepato-slandered drug. There were significant changes in serum biochemical parameters such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), bilirubin, albumin, total protein, and γ-glutamyl transferase (GGT) in carbon tetrachloride intoxicated rats, which were restored towards normal values in C. intybus-treated animals. Histopathological examination of liver tissues further substantiated these findings. In conclusion, of this investigation, the results ascertain that the herb extracts of C. intybus possess significant hepatoprotective activity.

Toxic effects of sub-chronic exposure of male albino rats to emamectin benzoate and possible ameliorative role of Foeniculum vulgare essential oil

Emamectin benzoate (EB) is an avermectin insecticide used extensively in pest control on vegetable and field crops. Few studies have been done for evaluating adverse effects of EB. In the current study, we evaluated the toxic effects of EB on male rats and the possible ameliorative role of fennel essential oil (FEO). Thirty two male rats were randomly divided into 4 equal groups. All groups were treated orally with distilled water (control group), 0.5mlFEOkg(-1) BW (FEO group), 2.5mgEBkg(-1) BW (EB group), and 0.5mlFEOkg(-1) BW+2.5mgEBkg(-1) BW (FEO+EB group) for 28 days. The obtained results showed that EB treatment resulted in a significant decrease in body weight, body weight gain, RBC count, Hb concentration, % PCV, MCV and MCHC. Moreover, EB significantly decreased total leukocyte, lymphocyte, monocyte and platelet count but significantly increased granulocyte count. EB markedly decreased total protein, albumin, globulin, IgG and IgM concentrations with a significant increase in TNF-α secretion. EB had a negative impact on the liver as it significantly increased ALT, ALP, and MDA, while decreasing SOD activity. Regarding to the histopathological examination, EB treatment induced coagulative necrosis and blood vessels congestion of the liver in treated rats. Furthermore, it resulted in depletion and necrosis of the white pulp of the spleen in treated rats. The co-administration of FEO with EB, however, improved the majority of parameters studied, suggesting that FEO is an important substance in decreasing toxic effects of EB.

Thiamine prescribing practices within university-affiliated hospitals: a multicenter retrospective review

BACKGROUND

Patients with suspected thiamine deficiency should receive treatment with parenteral thiamine to achieve the high serum thiamine levels necessary to reverse the effects of deficiency and to circumvent problems with absorption common in the medically ill.

OBJECTIVE

To quantify rates of parenteral administration of thiamine across university-affiliated hospitals and to identify factors associated with higher rates of parenteral prescribing.

DESIGN

Multicenter, retrospective observational study of thiamine prescriptions.

METHODS

Prescriptions for thiamine were captured from computerized pharmacy information systems across participating centers, providing information concerning dose, route, frequency, and duration of thiamine prescribed from January 2010 to December 2011.

SETTING

Fourteen university-affiliated tertiary care hospitals geographically distributed across Canada, including 48,806 prescriptions for thiamine provided to 32,213 hospitalized patients.

RESULTS

Parenteral thiamine accounted for a statistically significant majority of thiamine prescriptions (57.6%, P < 0.001); however, oral thiamine constituted a significant majority of the total doses prescribed (68.4%, z = 168.9; P < 0.001). Protocols prioritizing parenteral administration were associated with higher rates of parenteral prescribing (61.3% with protocol, 45.8% without protocol; P < 0.001). Patients admitted under psychiatry services were significantly more likely to be prescribed oral thiamine (P < 0.001).

CONCLUSIONS

Although parenteral thiamine accounted for a statistically significant majority of prescriptions, oral thiamine was commonly prescribed within academic hospitals. Additional strategies are needed to promote parenteral thiamine prescribing to patients with suspected thiamine deficiency.

Sub-chronic exposure to fipronil induced oxidative stress, biochemical and histopathological changes in the liver and kidney of male albino rats

Fipronil (FPN) is a broad-spectrum N-phenylpyrazole insecticide and has been used in agriculture and public health since the mid-1990s. The present study was designed to investigate the adverse effects of sub-chronic exposure to the FPN on the liver and kidney of male rats at three concentrations 0.1, 1 and 10 mg/L in drinking water for 45 days. Serum aspartate aminotransferases (AST), alanine aminotransferases (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) activity and levels of uric acid, creatinine and total protein were significantly increased in FPN-treated rats. Oxidative stress biomarkers such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reduced (GSH) were significantly decreased, while lipid peroxidation (LPO) was significantly increased in treating rats in a concentration dependent manner. FPN caused histopathological alterations in liver and kidney of male rats. From our results, it can be concluded that FPN induced lipid peroxidation, oxidative stress, liver, and kidney injury in rats. These pathophysiological changes in liver and kidney tissues could be due to the toxic effect of FPN that associated with a generation of free radicals.

A framework for inter-level explanations: outlines for a new explanatory pluralism

According to explanatory pluralism, the appropriate explanatory level is determined by pragmatic factors, and there are no general exclusion or preference rules concerning higher- or lower-level explanations. While I agree with the latter claim, I will argue that the former is in need of revision. In particular, I will argue that by distinguishing cases of two explanations being descriptions of one underlying causal process, and two explanations being descriptions of two distinct causal processes, it becomes clear that the grain size of an explanation is in fact determined by the interplay of various pragmatic and non-pragmatic factors. Within these constraints, positive guidelines can be developed to direct us to the appropriate explanatory level. This gives us the outlines for a general framework for classifying various types of relations between explanations on different levels. After making a comparison between this new framework and standard explanatory pluralism, I end by suggesting some ways in which the framework could be further developed.

Neuropathology of alcoholism

Chronic alcohol consumption results in structural changes to the brain. In alcoholics without coexisting thiamine deficiency or liver disease this is largely restricted to a loss of white-matter volume. When it occurs, neuronal loss is limited in anatomic distribution and only detected with quantitative techniques. This relative paucity of neurodegeneration is reflected in studies of gene and protein expression in postmortem brain where findings are subtle and discordant between studies. In alcoholics with coexisting pathologies, neuronal loss is more marked and affects a wider range of anatomic regions, especially subcortical nuclei. Although this more widespread damage may reflect a more severe drinking history, there is evidence linking thiamine deficiency and the consequences of liver disease to the pathogenesis of alcohol-related brain damage. Furthermore, a range of other factors, such as cigarette smoking and mood disorders, that are common in alcoholics, have the potential to influence studies of brain pathology and should be considered in further studies of the neuropathology of alcoholism.

Wernicke-Korsakoff-syndrome: under-recognized and under-treated

BACKGROUND

Wernicke-Korsakoff syndrome (WKS) is a well described syndrome of neurological and cognitive problems that comprises both Wernicke's encephalopathy (WE) and Korsakoff syndrome (KS). WE is an acute neuropsychiatric disorder caused by thiamine deficiency. KS is a chronic consequence of thiamine deficiency with prominent impairment in memory formation.

METHOD

The authors review the literature on the pathophysiology, presentation, and treatment of WKS, focusing on the acute identification and treatment of WE.

RESULTS

Most cases of WE are missed by clinicians, likely because patients do not present with the classic signs associated with the condition. Attaining high serum levels of thiamine during treatment may be important to restore cognitive function as quickly as possible, though the exact dosing and route needed for effective treatment is unknown. Data indicates that the administration of intravenous (IV) thiamine has little risk.

CONCLUSION

In order to prevent this potentially devastating disease, physicians should have a high index of suspicion for WKS and dose thiamine accordingly.

Thiamine for prevention and treatment of Wernicke-Korsakoff Syndrome in people who abuse alcohol

BACKGROUND

Autopsy studies suggest that Wernicke-Korsakoff syndrome (WKS) is not a rare disorder, particularly in individuals who abuse alcohol. Thiamine has been established as the treatment of choice for over 50 years, but uncertainty remains about appropriate dosage and duration. Current practice guidelines are based on case reports and clinical experience. This is an update of a review first published in 2004 and last updated in 2008.

OBJECTIVES

• To assess the efficacy of thiamine in preventing and treating the manifestations of WKS due to excess alcohol consumption. • To determine the optimum form, dose and duration of thiamine treatment for this indication.

SEARCH METHODS

ALOIS, the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group (CDCIG), The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL and LILACS were searched on 6 September 2012 using the term thiamine OR aneurine. ALOIS contains records from all major health care databases (The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL, LILACS) as well as from many trial databases and grey literature sources.

SELECTION CRITERIA

Any randomised trials comparing thiamine with alternative interventions or comparing different thiamine regimens (varying in formulation, dose or duration of administration).

DATA COLLECTION AND ANALYSIS

All abstracts were independently inspected by two reviewers (ED and PWB), and relevant articles were retrieved and assessed for methodological quality using criteria provided in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

Two studies were identified that met the inclusion criteria, but only one contained sufficient data for quantitative analysis. Ambrose (2001) randomly assigned participants (n = 107) to one of five doses of intramuscular thiamine and measured outcomes after 2 days of treatment. We compared the lowest dose (5 mg/day) with each of the other four doses. A significant difference favoured 200 mg/day compared with the 5-mg/day dose in determining the number of trials needed to meet inclusion criteria on a delayed alternation test (mean difference (MD) -17.90, 95% confidence interval (CI) -35.4 to -0.40, P = 0.04). No significant differences emerged when the other doses were compared with 5 mg/day. The pattern of results did not reflect a simple dose-response relationship. The study had methodological shortcomings in design and in the presentation of results that limited further analysis.

AUTHORS' CONCLUSIONS

Evidence from randomised controlled clinical trials is insufficient to guide clinicians in determining the dose, frequency, route or duration of thiamine treatment for prophylaxis against or treatment of WKS due to alcohol abuse.

Supplementary thiamine is still important in alcohol dependence

AIMS

To assess the effect of mandatory thiamine enrichment of wheat flour on blood thiamine levels in an alcohol-dependent population.

METHODS

Alcohol-dependent clients (n = 100) entering an inpatient service for the management of alcohol withdrawal had thiamine blood tests and diet interviews. Approximately half (n = 46) the alcohol-dependent participants reported taking vitamin supplements prior to admission. Standard treatment included thiamine supplementation in the form of an intramuscular injection and 100 mg tablets. If consent was gained, a second thiamine blood test was taken prior to discharge (n = 77). Control participants (n = 20) with no history of treatment for alcohol abuse had thiamine blood tests and diet interviews.

RESULTS

Control participants consumed significantly larger amounts of thiamine in their diet compared with alcohol-dependent participants (P < 0.0001). Alcohol-dependent participants who reported no use of vitamin supplements had significantly lower (P < 0.05) blood thiamine levels compared with controls, whereas controls and those who reported using vitamin supplements had no significant difference. No significant correlation was found between thiamine blood levels and reported levels of alcohol consumption.

CONCLUSION

Reduced blood levels of thiamine in people who are alcohol dependent, compared with those with no history of alcohol abuse, are likely to be because of the poor diet. Consumption of vitamin supplements appears to bring thiamine levels closer to those seen in control participants. Supplementation of dietary intake of thiamine in people who are alcohol dependent remains an important measure for the prevention of Wernicke-Korsakoff's syndrome in this population.

Wernicke's encephalopathy: expanding the diagnostic toolbox

Wernicke's encephalopathy (WE) is a life threatening neurological disorder that results from thiamine (Vitamin B1) deficiency. Clinical signs include mental status changes, ataxia, occulomotor changes and nutritional deficiency. The conundrum is that the clinical presentation is highly variable. WE clinical signs, brain imaging, and thiamine blood levels, are reviewed in 53 published case reports from 2001 to 2011; 81 % (43/53) were non-alcohol related. Korsakoff Syndrome or long-term cognitive neurological changes occurred in 28 % (15/53). Seven WE cases (13 %) had a normal magnetic resonance image (MRI). Four WE cases (8 %) had normal or high thiamine blood levels. Neither diagnostic tool can be relied upon exclusively to confirm a diagnosis of WE.

EFNS guidelines for diagnosis, therapy and prevention of Wernicke encephalopathy

BACKGROUND

Although Wernicke encephalopathy (WE) is a preventable and treatable disease it still often remains undiagnosed during life.

OBJECTIVES

To create practical guidelines for diagnosis, management and prevention of the disease.

METHODS

We searched MEDLINE, EMBASE, LILACS, Cochrane Library.

CONCLUSIONS AND RECOMMENDATIONS

1 The clinical diagnosis of WE should take into account the different presentations of clinical signs between alcoholics and non alcoholics (Recommendation Level C); although prevalence is higher in alcoholics, WE should be suspected in all clinical conditions which could lead to thiamine deficiency (good practice point - GPP). 2 The clinical diagnosis of WE in alcoholics requires two of the following four signs; (i) dietary deficiencies (ii) eye signs, (iii) cerebellar dysfunction, and (iv) either an altered mental state or mild memory impairment (Level B). 3 Total thiamine in blood sample should be measured immediately before its administration (GPP). 4 MRI should be used to support the diagnosis of acute WE both in alcoholics and non alcoholics (Level B). 5 Thiamine is indicated for the treatment of suspected or manifest WE. It should be given, before any carbohydrate, 200 mg thrice daily, preferably intravenously (Level C). 6 The overall safety of thiamine is very good (Level B). 7 After bariatric surgery we recommend follow-up of thiamine status for at least 6 months (Level B) and parenteral thiamine supplementation (GPP). 8 Parenteral thiamine should be given to all at-risk subjects admitted to the Emergency Room (GPP). 9 Patients dying from symptoms suggesting WE should have an autopsy (GPP).

Wernicke's encephalopathy in advanced gastric cancer

PURPOSE

With their prolonged survival and malnutrition, cancer patients, and especially gastrointestinal (GI) tract cancer patients, can develop Wernicke's encephalopathy (WE). The aim of this study is to remind physicians of the importance of WE and prompt management in patients with GI tract cancer.

MATERIALS AND METHODS

This study is a retrospective review of 2 cases of WE in advanced gastric cancer (AGC) patients, and we review the literature for cases of GI tract cancer related to WE.

RESULTS

A 48-year-old female with AGC presented dizziness and diplopia for 5 days and a 20 kg weight loss. Neurologic exam showed nystagmus and gaze disturbance. Her symptoms improved after daily parenteral injection of thiamine 100 mg for 17 days. A 58-year-old female with AGC presented with sudden disorientation, confusion and 15 kg weight loss. Neurologic exam showed gaze limitation and mild ataxia. Despite daily parenteral injection of thiamine 100 mg for 4 days, she died 5 days after the onset of neurologic symptoms. Combining the cases noted in the literature review with our 2 cases, the 7 gastric cancer cases and 2 colorectal cancer cases related to WE showed similar clinical characteristics; 1) a history of long-period malnutrition and weight loss, 2) relatively typical neurologic signs and symptoms and 3) specific magnetic resonance image findings. Except for 2 patients who had irreversible neurologic symptoms, the other 7 patients were improved with prompt thiamine treatment.

CONCLUSION

It is important to consider WE in GI tract cancer patients with acute neurologic symptoms and who are in a state of malnutrition. Thiamine should be given as soon as possible when WE is suspected.

Neurologic presentations of nutritional deficiencies

Optimal functioning of the central and peripheral nervous system is dependent on a constant supply of appropriate nutrients. The first section of this review discusses neurologic manifestations related to deficiency of key nutrients such as vitamin B(12), folate, copper, vitamin E, thiamine, and others. The second section addresses neurologic complications related to bariatric surgery. The third sections includes neurologic presentations caused by nutrient deficiencies in the setting of alcoholism. The concluding section addresses neurologic deficiency diseases that have a geographic predilection.