Wernicke's encephalopathy in non-alcoholics. An autopsy study

Hyperemesis Gravidarum Complicated by Wernicke's Encephalopathy: A Case Report

Wernicke's encephalopathy (WE) is a rare neurologic disease caused by a deficiency in thiamine (B1). It is characterized by features of altered mental status, cerebellar dysfunction, and ophthalmoplegia. Most often, cases are attributed to long-term alcohol use; however, rarer causes have been described in the literature. In this article, we describe a case of WE caused by hyperemesis gravidarum in a 19-year-old female with no known medical history.

Ascariasis, trichuriasis and fatal non-transfusion

Blood transfusion for chronic anemia can lead to acute or decompensated heart failure in patients who have fluid overload as part of their compensatory response and/or have intrinsic heart disease, and then it could be fatal in such clinical scenarios. This is the report of a case of profound chronic anemia in a young male patient, who was not transfused and then developed confusion followed by terminal cardiopulmonary arrest. Autopsy revealed severe trichuriasis to be the cause of the anemia, along with severe ascariasis, but minimal intrinsic brain disease. This supports the conclusion that anemia was the cause of the confusion, and the lesson that confusion may be a sign that the benefit of blood transfusion outweighs the risk in a patient with severe chronic anemia.

Atypical neuroleptic malignant syndrome and non-alcoholic Wernicke's encephalopathy

We report the case of a middle-aged woman with a history of bipolar disorder, in the absence of alcohol or substance misuse. The patient had been maintained on fluphenazine decanoate depot and now presented acutely with cognitive dysfunction and rigidity. Laboratory tests revealed elevated creatine kinase, acute kidney injury with metabolic acidosis and transaminitis, leading to a provisional diagnosis of neuroleptic malignant syndrome (NMS). Neuroleptics were withheld; dialysis was commenced; and blood biochemistry parameters improved in tandem. However, mental status changes persisted, and re-evaluation revealed multidirectional nystagmus with bilateral past-pointing. MRI confirmed the diagnosis of Wernicke's encephalopathy (WE). Prompt recovery followed treatment with high-dose intravenous thiamine. We discuss the co-occurrence of NMS and non-alcoholic WE-highlighting the need for a high index of suspicion for these relatively rare neuropsychiatric diagnoses which are often missed in those with atypical presentations.

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.

Don't seek, don't find: The diagnostic challenge of Wernicke's encephalopathy

Wernicke’s encephalopathy is caused by thiamine deficiency and has a range of presenting features, including gait disturbance, altered cognitive state, nystagmus and other eye movement disorders. In the past, Wernicke’s encephalopathy was described almost exclusively in the alcohol-dependent population. However, in current times, Wernicke’s encephalopathy is also well recognized in many other patient groups, including patients following bariatric surgery, gastrointestinal surgery, cancer and pancreatitis. Early recognition of Wernicke’s encephalopathy is vital, as prompt treatment can restore cognitive or ocular function and can prevent permanent disability. Unfortunately, Wernicke’s encephalopathy is often undiagnosed – presumably because it is relatively uncommon and has a variable clinical presentation. Clinical biochemists have a unique role in advising clinicians about potential nutritional or metabolic causes of unexplained neurological symptoms and to prompt consideration of thiamine deficiency as a potential cause in high-risk patient groups. The aim of this review is to summarize the clinical features, diagnosis and treatment of Wernicke’s encephalopathy and to highlight some non-traditional causes, such as after bariatric surgery.

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.

Clinical characteristics and magnetic resonance imaging findings in nine patients with nonalcoholic Wernicke's encephalopathy: a retrospective study

PURPOSE

Wernicke's encephalopathy (WE) is a severe neurological disorder caused by thiamine deficiency. The most common cause of WE is alcoholism. However, there is a significant paucity of information in the existing literature relating to nonalcoholic WE. In this study, we investigated the clinical characteristics and neuroimaging findings of nine patients with nonalcoholic WE.

PATIENTS AND METHODS

We retrospectively collated clinical data from nine patients who had been diagnosed with WE in accordance with established criteria including age, gender, risk factors and clinical manifestations. We also collated initial hematological and neuroimaging findings.

RESULTS

The mean age of the nine patients was 54.0±17.1 years; four of these patients (44.4%) were male. All nine patients had a history of fasting (range, 5-47 days) prior to WE. Four of the nine patients (44.4%) exhibited the classical triad, and eight (88.9%) showed alterations in mental status. Magnetic resonance imaging (MRI) scans showed that all nine patients had symmetric lesions of the medial thalamus. MRI also revealed other WE-related lesions in mammillary bodies (22.2%), the periaqueductal region (55.6%), the tectal plate of the midbrain (77.8%), cranial nerve nuclei (77.8%) and in the symmetric subcortical white matter (11.1%).

CONCLUSION

Our analysis showed that fasting is a common cause of WE in nonalcoholic patients and that MRI is a useful tool for the diagnosis of WE. The most common MRI findings were symmetrical lesions of the medial thalamus lesions, followed by the tectal plate of the midbrain and cranial nerve nuclei.

Review of thiamine deficiency disorders: Wernicke encephalopathy and Korsakoff psychosis

Wernicke encephalopathy (WE) and Korsakoff psychosis (KP), together termed Wernicke-Korsakoff syndrome (WKS), are distinct yet overlapping neuropsychiatric disorders associated with thiamine deficiency. Thiamine pyrophosphate, the biologically active form of thiamine, is essential for multiple biochemical pathways involved in carbohydrate utilization. Both genetic susceptibilities and acquired deficiencies as a result of alcoholic and non-alcoholic factors are associated with thiamine deficiency or its impaired utilization. WKS is underdiagnosed because of the inconsistent clinical presentation and overlapping of symptoms with other neurological conditions. The identification and individualized treatment of WE based on the etiology is vital to prevent the development of the amnestic state associated with KP in genetically predisposed individuals. Through this review, we bring together the existing data from animal and human models to expound the etiopathogenesis, diagnosis, and therapeutic interventions for WE and KP.

Non-alcoholic Wernicke's encephalopathy with cortical involvement and polyneuropathy following gastrectomy

In this study, we present the clinical manifestations, brain magnetic resonance imaging (MRI) and concurrent polyneuropathies in two patients with non-alcoholic Wernicke's encephalopathy (WE) after gastrojejunostomy (Billroth II) anastomosis procedures. These patients developed sub-acute onset of disorientation and disturbance of consciousness following several weeks of poor intake. Peripheral neuropathy of varying severity was noted before and after the onset of WE. Brain MRI of the patients showed cerebellar vermis and symmetric cortical abnormalities in addition to typical WE changes. Electrophysiological studies demonstrated axonal sensorimotor polyneuropathy. Prompt thiamine supplement therapy was initiated and both patients gradually recovered, however mild amnesia was still noted 6 months later. We reviewed non- alcoholic WE with atypical cortical abnormalities in English language literatures and identified 29 more cases. Eight out of 31 (25.8%) patients died during follow-up. Nine patients with gait disturbance or motor paresis had showed hyporeflexia in neurological examinations. In addition to classic triad, seizure was recorded in seven patients. Dietary deprivation is a risk factor for non-alcoholic WE among elderly patients receiving gastrointestinal surgery. The prognosis is good after thiamine supplement therapy. Recognizing the MRI features and predisposing factors in patients who have undergone gastrectomy can aid in the diagnosis and management.

Wernicke’s Encephalopathy in a Patient Without Chronic Alcohol Abuse

Wernicke’s encephalopathy (WE) is traditionally seen in the emergency department in patients with chronic alcohol abuse. WE can result in significant morbidity and mortality if untreated, making early diagnosis and intervention paramount. We discuss a case of WE in a 63-year-old female with no history of chronic alcohol abuse, who presented with bilateral opthalmoplegia that resolved after intravenous thiamine administration. This case report highlights the varied clinical settings other than chronic alcohol abuse in which the diagnosis of WE should be considered.

Magnetic resonance imaging in the assessment of brain involvement in alcoholic and nonalcoholic Wernicke’s encephalopathy

AIM

To present the typical and atypical magnetic resonance (MR) imaging findings of alcoholic and non-alcoholic Wernicke’s encephalopathy.

METHODS

This study included 7 patients with Wernicke’s encephalopathy (2 men, 5 women; mean age, 52.3 years) that underwent brain MR examination between January 2012 and March 2016 in a single institution. Three patients were alcoholics and 4 patients were non-alcoholics. MR protocol included a T2-weighted sequence, a fluid attenuation inversion recovery (FLAIR) sequence, a diffusion-weighted sequence (b = 0 and 1000 s/mm²), and a contrast-enhanced MR sequence. All MR images were retrospectively reviewed at baseline and follow-up by two radiologists.

RESULTS

All patients with Wernicke’s encephalopathy had bilateral areas showing high signal intensity on both T2-weighted and FLAIR MR images in the typical sites (i.e., the periaqueductal region and the tectal plate). Signal intensity abnormalities in the atypical sites (i.e., the cerebellum and the cerebellar vermis) were seen in 4 patients, all of which had no history of alcohol abuse. Six patients had areas with restricted diffusion in the typical and atypical sites. Four patients had areas showing contrast-enhancement in the typical and atypical sites. Follow-up MR imaging within 6 mo after therapy (intravenous administration of thiamine) was performed in 4 patients, and demonstrated a complete resolution of all the signal intensities abnormalities previously seen in all patients.

CONCLUSION

MR imaging is valuable in the diagnosis of Wernicke’s encephalopathy particularly in patients presenting with atypical clinical symptoms, or with no history of alcohol abuse.

Wernicke's Encephalopathy, Wet Beriberi, and Polyneuropathy in a Patient with Folate and Thiamine Deficiency Related to Gastric Phytobezoar

Background. Wernicke's encephalopathy (WE) is an acute neurological disorder resulting from thiamine deficiency. It is mainly related to alcohol abuse but it can be associated with other conditions such as gastrointestinal disorders. This vitamin deficiency can also present with cardiovascular symptoms, called “wet beriberi.” Association with folate deficit worsens the clinical picture. Subject. A 70-year-old man with gastric phytobezoar presented with gait instability, dyspnoea, chest pain associated with right heart failure and pericarditis, and folate deficiency. Furosemide was administered and cardiac symptoms improved but he soon developed vertiginous syndrome, nystagmus, diplopia, dysmetria, and sensitive and motor deficit in all four limbs with areflexia. Results. A cerebral magnetic resonance imaging (MRI) showed typical findings of WE. He was immediately treated with thiamine. Neurological symptoms improved in a few days and abnormal signals disappeared in a follow-up MRI two weeks later. Conclusion. Patients with malabsorption due to gastrointestinal disorders have an increased risk of thiamine deficiency, and folate deficiency can make this vitamin malabsorption worse. An established deficiency mainly shows neurological symptoms, WE, or rarely cardiovascular symptoms, wet beriberi. Early vitamin treatment in symptomatic patients improves prognosis. We recommend administration of prophylactic multivitamins supplements in patients at risk as routine clinical practice.

Association between malignancy and non-alcoholic Wernicke's encephalopathy: a case report and literature review

Background

Wernicke's encephalopathy is a serious medical condition associated with high morbidity and mortality caused by deficiency of thiamine. This disease is classically associated with alcoholism, but is underappreciated in the nonalcoholic population. There is growing acknowledgement of the development of Wernicke's encephalopathy in patients with malignancies.

Methods

We conducted a literature review in PubMed for cases of Wernicke's encephalopathy occurring in patients with malignancy. We also present the case of a 47-year-old woman with recurrent laryngeal cancer and multiple hospital admissions for malnutrition. Neurological examination was notable for pendular nystagmus, severe gait ataxia, confusion, and poor memory consolidation. MRI of the brain was significant for T2-weighted fluid-attenuated inversion recovery hyperintensities in periaqueductal regions, medial thalami, and the tectal plate, typical for Wernicke's encephalopathy. She was treated with thiamine repletion, and had marked improvement in her mental status and some improvement in her vision problems and ataxia, although some nystagmus and significant short-term memory impairment persisted.

Results

The literature review yielded dozens of case reports of Wernicke's encephalopathy in patients with malignancy, dominated by cases of patients with malignancies of the gastrointestinal system, followed by those with hematologic malignancies.

Conclusions

Malignancy is an important risk factor for the development of Wernicke's encephalopathy. This diagnosis is underappreciated and difficult for the clinician to discern from multifactorial delirium. Clinicians should be aware to treat at-risk patients with thiamine immediately, especially if multiple risk factors are present.

Role of astrocytes in thiamine deficiency

Thiamine deficiency (TD) is the underlying cause of Wernicke's encephalopathy (WE), an acute neurological disorder characterized by structural damage to key periventricular structures in the brain. Increasing evidence suggests these focal histological lesions may be representative of a gliopathy in which astrocyte-related changes are a major feature of the disorder. These changes include a loss of the glutamate transporters GLT-1 and GLAST concomitant with elevated interstitial glutamate levels, lowered brain pH associated with increased lactate production, decreased levels of GFAP, reduction in the levels of glutamine synthetase, swelling, alterations in levels of aquaporin-4, and disruption of the blood-brain barrier. This review focusses on how these manifestations contribute to the pathophysiology of TD and possibly WE.

Clinical evaluation and biochemical analyses of thiamine deficiency in Pacific harbor seals (Phoca vitulina) maintained at a zoological facility

OBJECTIVE

To determine thiamine-dependent enzyme activities in various tissue samples of Pacific harbor seals (Phoca vitulina) and thiaminase activities in dietary fish.

DESIGN

Cross-sectional study.

ANIMALS

11 Pacific harbor seals with thiamine deficiency and 5 control seals.

PROCEDURES

Seals underwent evaluation to rule out various diseases and exposure to toxins. For seals that died, measurement of thiamine-dependent enzymes in liver and brain samples and determination of mitochondrial DNA (mtDNA) copy number in liver, brain, and muscle samples were performed. Thiaminase activity in dietary fish was determined.

RESULTS

8 seals with thiamine deficiency died. Affected seals typically had acute neurologic signs with few nonspecific findings detected by means of clinicopathologic tests and histologic examination of tissue samples. Thiamine-dependent enzyme activities in liver samples of affected seals were significantly lower than those in control liver samples. The primary activation ratios and latencies for enzymes indicated that brain tissue was more affected by thiamine deficiency than liver tissue. Activities of pyruvate dehydrogenase were more affected by thiamine deficiency than those of transketolase and ketoglutarate dehydrogenase. For control seals, the mtDNA copy number in muscle samples was significantly lower than that for affected seals; conversely, the copy number in control liver samples was significantly greater than that of affected seals. Thiaminase activity was substantially higher in smelt than it was in other types of dietary fish.

CONCLUSIONS AND CLINICAL RELEVANCE

Results of analyses in this study confirmed a diagnosis of thiamine deficiency for affected seals resulting from high thiaminase activity in dietary fish, inadequate vitamin administration, and increased thiamine demand caused by pregnancy and lactation.

Recurrent Wernicke's Encephalopathy in a 16-Year-Old Girl with Atypical Clinical and Radiological Features

Background. Wernicke's Encephalopathy (WE) is a clinical diagnosis with serious neurological consequences. Its occurrence is underestimated in nonalcoholics and is uncommon in adolescents. We aim to draw the attention to a rare case, which had additional clinical and radiological features. Case. A 16-year-old girl presented with three-week history of vomiting secondary to intestinal obstruction. She developed diplopia soon after hospitalization. Neurological evaluation revealed restriction of bilateral lateral recti with horizontal nystagmus, and bilateral limb dysmetria. Brain MRI was normal. She had prompt improvement to thiamine. Four months later, she presented with headache, bilateral severe deafness, and tinnitus. Clinically, she had severe sensorineural hearing loss, bilateral lateral recti paresis, and gait ataxia. CT head showed bilateral caudate nucleus hypodensities. MRI brain revealed gadolinium enhancement of mamillary bodies and vermis. She had significant improvement after IV thiamine. Headache completely resolved while the ocular movements, hearing, and tinnitus improved partially in 72 hours. Conclusions. Recurrent WE in adolescence is uncommon. Headache, tinnitus, and deafness are rare clinical features. Although MRI study shows typical features of WE, the presence of bilateral caudate nuclei hypodensities on CT scan is uncommon. Prompt treatment with thiamine is warranted in suspected cases to prevent permanent neurological sequelae.

Neurologic complications of bone marrow transplantation

Although bone marrow transplantation has been recognized as an effective therapy for malignant and nonmalignant blood disorders, the modality has also been associated with side-effects and complications. Among these adverse events, neurologic complications emerged as an important and frequent source of treatment-related morbidity and mortality. The survival of patients who died from complications related to central nervous system abnormalities appears to be shorter compared to those who died from non-neurological complications. The incidence of neurologic complications appears to correlate with the degree of human leukocyte antigen (HLA) disparity and the risk status of the underlying disease. Nonrelapse mortality associated with reduced intensity regimens is lower compared to myeloablative conditioning regimens. However, reduced intensity regimens are still associated with significant incidence of complications, including graft-versus-host disease, opportunistic infections, organ toxicity, and neurologic complications. Complications of sepsis-related encephalopathy in mechanically ventilated patients are frequently either overlooked or misdiagnosed. Obtaining a microbiological diagnosis through body fluid cultures or tissue identification is important in order to identify the source of infection and guide an effective antimicrobial therapy. However, pursuing a microbiological diagnosis must not delay the administration of antibiotics and resuscitation of a patient with septic shock.

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.

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.

Loss of astrocytic glutamate transporters in Wernicke encephalopathy

Wernicke encephalopathy (WE), a neurological disorder caused by thiamine deficiency (TD), is characterized by structural damage in brain regions that include the thalamus and cerebral cortex. The basis for these lesions is unclear, but may involve a disturbance of glutamatergic neurotransmission. We have therefore investigated levels of the astrocytic glutamate transporters EAAT1 and EAAT2 in order to evaluate their role in the pathophysiology of this disorder. Histological assessment of the frontal cortex revealed a significant loss of neurons in neuropathologically confirmed cases of WE compared with age-matched controls, concomitant with decreases in alpha-internexin and synaptophysin protein content of 67 and 52% by immunoblotting. EAAT2 levels were diminished by 71% in WE, with levels of EAAT1 also reduced by 62%. Loss of both transporter sites was confirmed by immunohistochemical methods. Development of TD in rats caused a profound loss of EAAT1 and EAAT2 in the thalamus accompanied by decreases in other astrocyte-specific proteins. Treatment of TD rats with N-acetylcysteine prevented the downregulation of EAAT2 in the medial thalamus, and ameliorated the loss of several other astrocyte proteins, concomitant with increased neuronal survival. Our results suggest that (1) loss of EAAT1 and EAAT2 glutamate transporters is associated with structural damage to the frontal cortex in patients with WE, (2) oxidative stress plays an important role in this process, and (3) TD has a profound effect on the functional integrity of astrocytes. Based on these findings, we recommend that early treatment using a combination of thiamine AND antioxidant approaches should be an important consideration in cases of WE.

Astrocytes are a major target in thiamine deficiency and Wernicke's encephalopathy

Thiamine deficiency (TD) is the underlying cause, and an established model, of Wernicke's encephalopathy (WE). Although the neurologic dysfunction and brain damage that results from TD has been well-described, the precise mechanisms that lead to the selective histological lesions characteristic of this disorder remain a mystery. Over the course of many years, various processes have been proposed that could lead to focal neuronal cell death in this disorder. But despite a concerted effort to relate these processes to a clear sequelae of events culminating in development of the focal neuropathology, little success has resulted. In recent years, however, a role for astrocytes in the pathophysiology of TD has been emerging. Here, alterations in glutamate uptake, and levels of the astrocytic glutamate transporters EAAT1 and EAAT2 in TD and WE, are discussed in terms of an excitotoxic event, along with the GABA transporter subtype GAT-3, and changes in other astrocytic proteins including GFAP and glutamine synthetase. Lactic acidosis, changes in the water channel protein AQP-4 and brain edema are also a focus of attention in relation to astrocyte dysfunction, while involvement of oxidative stress and inflammatory processes, along with white matter injury in terms of excitotoxicity are other key issues considered. In summary, a new appraisal of the extent of involvement of astrocytes in TD and WE is presented, with the evidence suggesting these cells represent a major target for damage during the disease process.

Neuroimaging findings in acute Wernicke's encephalopathy: review of the literature

OBJECTIVE

Wernicke's encephalopathy is an acute neurological syndrome resulting from thiamine (vitamin B1) deficiency. Early recognition is important because timely thiamine supplementation can reverse the clinical features of the disease. The aim of this article is to provide an update on the typical and atypical neuroimaging findings of the acute phase of the disease.

CONCLUSION

Wernicke's encephalopathy is characterized by a quite distinct pattern of MR alterations, which include symmetrical alterations in the thalami, mamillary bodies, tectal plate, and periaqueductal area, but atypical alterations may also been seen. A thorough knowledge of the neuroimaging findings of Wernicke's encephalopathy will assist in arriving at an early diagnosis, thus reducing the morbidity and mortality associated with this disease.

MR imaging findings in 56 patients with Wernicke encephalopathy: nonalcoholics may differ from alcoholics

BACKGROUND AND PURPOSE

Wernicke encephalopathy (WE) is a severe neurologic disorder resulting from dietary vitamin B(1) deficiency. This study was undertaken to analyze and compare MR imaging findings and neurologic manifestations at clinical presentations of patients with WE with and without a history of alcohol abuse.

MATERIALS AND METHODS

WE patients were identified using diagnostic neurologic data bases. Fifty-six patients (29 females, 27 males) diagnosed between 1999 and 2008 with WE who improved within 1 month from the onset of thiamine administration were included in the analysis. Patients' records were reviewed for clinical manifestations and imaging studies' findings. MR imaging was performed in the acute phase of the disease at a field strength of 1T (16 patients) and 1.5T (40 patients). All MR images were of acceptable to good quality and were retrospectively reviewed. We compared imaging findings and clinical presentation in the alcoholic (AL) group versus the non-alcoholic (NA) group using the 2-tailed Fisher exact test and the Phi coefficient as appropriate.

RESULTS

Forty-three percent of the patients were in the AL group, whereas 57% were in the NA group. Eighty-nine percent showed changes in consciousness, 75% had ocular manifestations, and 54% had ataxia. On MR imaging, 80% of the patients had evidence of symmetric lesions in the medial thalami and in the periventricular region of the third ventricle; 59%, in the periaqueductal area; 45%, in the mamillary bodies; 36%, in the tectal plate; and 7%, in the periventricular gray matter located anteriorly to the fourth ventricle. Signal-intensity alterations in areas considered atypical for the disease were noted only in the NA group and always in association with the typical findings. Contrast enhancement of the thalamus and mamillary bodies was significantly associated with alcohol abuse.

CONCLUSIONS

Contrast enhancement in the mamillary bodies and thalamus is a typical finding of the disease in AL patients. Atypical MR imaging findings characterize NA patients.

Wernicke's encephalopathy: new clinical settings and recent advances in diagnosis and management

Wernicke's encephalopathy is an acute neuropsychiatric syndrome resulting from thiamine deficiency, which is associated with significant morbidity and mortality. According to autopsy-based studies, the disorder is still greatly underdiagnosed in both adults and children. In this review, we provide an update on the factors and clinical settings that predispose to Wernicke's encephalopathy, and discuss the most recent insights into epidemiology, pathophysiology, genetics, diagnosis, and treatment. To facilitate the diagnosis, we classify the common and rare symptoms at presentation and the late-stage symptoms. We emphasise the optimum dose of parenteral thiamine required for prophylaxis and treatment of Wernicke's encephalopathy and prevention of Korsakoff's syndrome associated with alcohol misuse. A systematic approach helps to ensure that patients receive a prompt diagnosis and adequate treatment.

Wernicke's encephalopathy in a patient with schizophrenia

Clinically, we most often associate Wernicke's encephalopathy (WE) with an alcohol abusing population. However, it is important to consider other causes of malnutrition and vitamin deficiency as risk factors for the development of this disorder. We present a case of a 51-year-old man with schizophrenia and malnutrition who presented with delirium, ophthalmoplegia, and seizures. He responded rapidly to the administration of IV thiamine. Because of the high rate of mortality and morbidity, WE should be high on the differential of any patient at risk for malnutrition or with ophthalmoplegia, regardless of alcohol history. This is particularly important in psychiatric patients where the syndrome may be masked and thus treatment delayed.

Pancreatic encephalopathy and Wernicke encephalopathy in association with acute pancreatitis: A clinical study

AIM: To investigate clinical characteristics and therapy of pancreatic encephalopathy (PE) and Wernicke encephalopathy (WE).

METHODS: In a retrospective study of 596 patients with acute pancreatitis (AP), patients with PE were compared to those with WE in regards to history, clinical manifestation, diagnosis, treatment and outcome.

RESULTS: There were 93 patients with severe acute pancreatitis (SAP). Encephalopathies were discovered in 10 patients (1.7%). Six patients with PE all developed in SAP (6.5%), and three of them died (3% of SAP, 50% of PE). Four patients with WE developed in AP (0.7%), and two of them died (0.3% of AP, 50% of WE). Two patients with WE were treated with parenteral thiamine and survived. Global confusions were seen in all patients with encephalopathy. Ocular abnormalities were found. Conjugate gaze palsies were seen in 1 of 6 (16.7%) patients with PE. Of 4 patients with WE, one (25%) had conjugate gaze palsies, two (50%) had horizontal nystagmus, three (75%) had diplopia, and one (25%) had myosis. Ataxia was not seen in all patients. None of patients with WE presented with the classic clinical triad. CSF examinations for 2 patients with WE showed lightly-increased proteins and glucose. CT and MRI of the brain had no evidence of characteristic abnormalities.

CONCLUSION: PE occurs in early or reiteration stage of SAP, and WE in restoration stage of SAP/AP. Ocular abnormalities are the hallmarks of WE, and horizontal nystagmus is common. It is difficult to diagnose earlier an encephalopathy as PE or WE, as well as differentiate one from the other. Long fasting, hyperemesis and total parenteral nutrition (TPN) without thiamine are main causes of thiamine deficiency in the course of pancreatitis.

Non-traumatic forensic neuropathology

The practicing Forensic Pathologist is likely to encounter case material in which either the cause of death or a major contribution to the cause of death is underlying damage to or disease of the central nervous system. While it is good practice in many instances to have a working relationship with a Department of Neuropathology, from which advice and practical help can be sought, there may be instances when the Forensic Pathologist needs to proceed on a basis of a working knowledge of Forensic Neuropathology up to and including how to examine the specimen and take tissue blocks for processing and subsequent histological examination. Some of the more common conditions of the central nervous system such as damage consequent to hypoxia-ischaemia, hypoglycemia and epilepsy, the encephalopathies associated with altered sodium concentration, deficiency due to Vitamin B(1) and various neurodegenerative diseases that manifest as dementia and include Alzheimer's disease, cortical Lewy body disease and the prion disorders, are outlined in this article.

Wernicke encephalopathy in nonalcoholic patients

BACKGROUND

Wernicke encephalopathy is associated with patients that have a history of alcohol abuse and other malnourished states. However, clinicians may be less likely to recognize this condition in nonalcoholic patients. This study was undertaken to evaluate the cause, diagnosis, treatment, and outcome of nonalcoholic patients with Wernicke encephalopathy.

METHODS

A retrospective review was conducted of all cases of Wernicke disease from 1984 to 1999 evaluated at a rural university hospital. Inclusion criteria consisted of patients diagnosed clinically with this disorder who improved after the administration of thiamin. Patients were also included in the series if they had classic pathologic findings of the disease on autopsy even without a prior clinical diagnosis.

RESULTS

Twelve patients were identified. Alcohol abuse was noted in only 50%. The patients without a history of alcohol abuse had other malnourished states, such as end-stage cancer, intractable vomiting after gastric reduction procedure, and prolonged hospital courses on intravenous fluids without other sources of nutrition. The mortality rate was 4 of 12 (33%) but due to multiple causes. Autopsies were performed on all 4 patients. Three of these 4 patients had no history of alcohol abuse. Two of the nonalcoholic patients were not diagnosed until autopsy, whereas all the patients with a history of alcohol abuse were diagnosed clinically.

DISCUSSION

Our study reveals that Wernicke encephalopathy continues to be a rare but life-threatening condition often overlooked in the nonalcoholic population, resulting in the further progression of an easily treatable condition.

Thiamin deficiency in HIV-positive patients: evaluation by erythrocyte transketolase activity and thiamin pyrophosphate effect

BACKGROUND AND AIMS

The aim of the study was to determine the thiamin status in HIV-positive patients.

METHODS

Measurement of erythrocyte transketolase activity (ETK) and thiaminpyrophosphate (TPP) effect in 55 consecutive HIV-positive patients of a specialized outpatient clinic were grouped into five groups according to their CD4 counts. Comparison of results of HIV-positive patients with age-matched control group of 22 healthy subjects.

RESULTS

Of the patients, 27% had a pathologically-increased TPP effect, 18% of the patients had pathologically-low ETK. The percentage of pathological values of TPP effect in the patients was significantly higher compared with the control group. There was no statistically significant correlation between pathological thiamin status and stage of the disease, zidovudine therapy or nutritional status of the patients.

CONCLUSIONS

Thiamin deficiency in HIV-positive patients was found in a higher percentage than previously reported. Thiamine deficiency is not only present in advanced stages of HIV-infection, but also in clinically asymptomatic patients.

Early diagnosis of pediatric Wernicke's encephalopathy

Wernicke's encephalopathy may be fatal if untreated. Because Wernicke's encephalopathy is suspected to be underdiagnosed in children, the authors wished to assess the frequency of overlooked diagnosis and to establish pertinent findings that could lead to early identification of pediatric Wernicke's encephalopathy. The authors performed multiple literature searches seeking pediatric patients with Wernicke's encephalopathy (age = 20 years or younger). A total of 30 patients was found, and the authors added a new patient. Each case report had its clinical, radiologic, and laboratory data, diagnostic method, and outcome analyzed. Of 31 patients, 16 were female and 15 male; the median age +/- S.D. was 11 +/- 6.5 years. The most frequent underlying disorder was malignancy in 11. Thirteen patients died undiagnosed, 16 recovered with thiamine therapy (eight with sequelae), and two died of infection soon after thiamine replacement was initiated. Only six presented with the Wernicke's encephalopathy clinical triad (mental status changes, ocular signs, and ataxia) at neurologic onset; nine eventually demonstrated this triad. The high rate of patients diagnosed only at postmortem examination (41.9%) confirms that Wernicke's encephalopathy is underdiagnosed in children. Thiamine therapy is warranted if any component of the Wernicke's encephalopathy triad is present in an appropriate clinical setting.

Mechanisms of neuronal cell death in Wernicke's encephalopathy

Wernicke's Encephalopathy (WE) is a serious neurological disorder resulting from thiamine deficiency, encountered in chronic alcoholics and in patients with grossly impaired nutritional status. Neuropathologic studies as well as Magnetic Resonance Imaging reveal selective diencephalic and brainstem lesions in patients with WE. The last decade has witnessed major advances in the understanding of pathophysiologic mechanisms linking thiamine deficiency to the selective brain lesions characteristic of WE. Activities of the thiamine-dependent enzyme alpha-ketoglutarate dehydrogenase, a rate-limiting tricarboxylic acid cycle enzyme are significantly reduced in autopsied brain tissue from patients with WE and from rats treated with the central thiamine antagonist, pyrithiamine. In the animal studies, evidence suggests that such enzyme deficits result in focal lactic acidosis, cerebral energy impairment and depolarization resulting from increased release of glutamate in vulnerable brain structures. It has been proposed that this depolarization may result in N-Methyl-D-Aspartate receptor-mediated excitotoxicity as well as increased expression of immediate early genes such as c-fos and c-jun resulting in apoptotic cell death. Other mechanisms involved in thiamine deficiency-induced cell loss may involve free radicals and alterations of the blood-brain barrier. Additional studies are still required to identify the site of the initial cellular insult and to explain the predilection of diencephalic and brainstem structures due to thiamine deficiency.

Neuropathology of thiamine deficiency disorders

The Wernicke-Korsakoff syndrome (WKS) is the most frequently encountered manifestation of thiamine deficiency in Western society. It is commonly seen in alcoholic patients, but may also occur in patients with impaired nutrition from other causes, such as those with gastrointestinal disease or AIDS. The pathology is restricted to the central nervous system and is characterised by neuronal loss, gliosis and vascular damage in regions surrounding the third and fourth ventricles and the cerebral aqueduct. In addition to WKS, thiamine deficiency may also result in beriberi, a cardiac and peripheral nervous system disease, and it has been implicated in the pathogenesis of cerebellar degeneration and peripheral neuropathy. Thus thiamine deficiency results in significant nervous system pathology and vigilance should be maintained in the diagnosis and treatment of this readily preventable cause of disease.