Wernicke encephalopathy: unusual findings in nonalcoholic patients

Brain MRI: A safe and a specific tool in the diagnosis of Gayet Wernicke's encephalopathy in pregnant women: Case report

Gayet-Wernicke encephalopathy (GWE) is a neuropsychiatric syndrome due to Vitamin B1 (thiamine) deficiency, fatal in 30% of cases and preventable if treatment is initiated early, characterized by the classic triad of encephalopathy, ocular involvement: ophthalmoplegia and/or nystagmus and ataxia. GWE is mainly observed in alcoholics, but can also appear in any state of malnutrition. In obstetrics, hyperemesis gravidarum can be complicated by GWE due to low thiamine stores and increased thiamine requirements. We report a case of Gayet-Wernicke encephalopathy complicating incoercible vomiting in a pregnant woman.

Wernicke Encephalopathy: Typical and Atypical Findings in Alcoholics and Non-Alcoholics and Correlation with Clinical Symptoms

PURPOSE

Clinical diagnosis of Wernicke encephalopathy (WE) can be challenging due to incomplete presentation of the classical triad. The aim was to provide an update on the relevance of standard MRI and to put typical and atypical imaging findings into context with clinical features.

METHODS

In this two-center retrospective observational study, the local radiology information system was searched for consecutive patients with clinical or imaging suspicion of WE. Two independent raters evaluated T2-weighted imaging (WI), fluid-attenuation inversion recovery (FLAIR), diffusion WI (DWI), T2*WI and/or susceptibility WI (SWI), and contrast-enhanced (CE)-T1WI, and noted the involvement of typical (i.e., mammillary bodies (MB), periaqueductal grey (PAG), thalamus, hypothalamus, tectal plate) and atypical (all others) lesion sites. Unusual signal patterns like hemorrhages were also documented. Reported clinical features together with the diagnostic criteria of the latest guidelines of the European Federation of Neurological Societies (EFNS) were used to test for relationships with MRI biomarkers.

RESULTS

47 patients with clinically confirmed WE were included (Jan '99-Apr '23; mean age, 53 yrs; 70% males). Interrater reliability for imaging findings was substantial (κ = 0.71), with lowest agreements for T2WI (κ = 0.85) compared to all other sequences and for PAG (κ = 0.65) compared to all other typical regions. In consensus, 77% (n = 36/47) of WE cases were rated MRI positive, with FLAIR (n = 36/47, 77%) showing the strongest relation (χ2 = 47.0; P < 0.001) compared to all other sequences. Microbleeds in the MB were detected in four out of ten patients who received SWI, not visible on corresponding T2*WI. Atypical findings were observed in 23% (n = 11/47) of cases, always alongside typical findings, in both alcoholics (n = 9/44, 21%) and non-alcoholics (n = 2/3, 67%). Isolated involvement of structures, explicitly PAG (n = 4/36; 11%) or MB (n = 1/36; 3%), was present but observed less frequently than combined lesions (n = 31/36; 86%). A cut-off width of 2.5 mm for the PAG on 2D axial FLAIR was established between cases and age- and sex-matched controls. An independent association was demonstrated only between short-term memory loss and changes in the MB (OR = 2.2 [95% CI: 1.1-4.5]; P = 0.024). In retrospect, EFNS criteria were positive (≥ 2 out of 4) in every case, but its count (range, 2-4) showed no significant (P = 0.427) relationship with signal changes on standard MRI.

CONCLUSION

The proposed sequence protocol (FLAIR, DWI, SWI and T1WI + CE) yielded good detection rates for neuroradiological findings in WE, with SWI showing microbleeds in the MB with superior detectability. However, false negative results in about a quarter of cases underline the importance of neurological alertness for the diagnosis. Awareness of atypical MRI findings should be raised, not only in non-alcoholics. There is limited correlation between clinical signs and standard MRI biomarkers.

Wernicke encephalopathy induced by glucose infusion: A case report and literature review

Introduction

Wernicke encephalopathy (WE) is a potentially fatal condition caused by thiamine (vitamin B1) deficiency. Chronic alcoholism is the most common cause of WE; however, other conditions responsible for thiamine deficiency should also be considered.

Case Report

We report the case of a 64-year-old woman with a history of diabetes who presented with confusion and apathy. Magnetic resonance imaging of the brain showed T2 hyperintensities involving dorsolateral medulla oblongata, tegmentum of the pons, vermis of the cerebellum, periaqueductal region, and the bilateral mammillary bodies. She had a history of intravenous glucose administration before her mental symptoms developed. On suspicion of WE, she was treated with a high dose of thiamine empirically. Her clinical condition improved rapidly in 2 weeks.

Conclusion

Endogenous thiamine stores can be rapidly depleted in the case of enhanced glucose oxidation. Patients who receive glucose should also be prescribed thiamine to avoid inducing or exacerbating WE.

An uncommon presentation of Wernicke-Korsakoff's syndrome in pregnancy: Case report

Wernicke's encephalopathy is an acute neuropsychiatric syndrome resulting from severe thiamine (vitamin B1) deficiency. Symptoms occur with an acute onset and may vary according to the brain area involved. Altered consciousness is the most common clinical feature, together with ocular abnormalities and ataxia. We report the case of a pregnant women affected by pre-gestational hyperthyroidism that caused an uncommon presentation of Wernicke's encephalopathy. Symptoms differed from the classic triad and diagnosis was made possible by a thorough analysis of anamnestic factors and brain MRI. Alongside thiamine supplementation, a multidisciplinary approach which included physiokinesis and a phoniatric support was fundamental for the patient's recovery.

Nonalcoholic Wernicke's Encephalopathy: A Retrospective Study from a Tertiary Care Center in Northern India

OBJECTIVE

The objective of this study was to describe the demographic features, clinical presentation, and management and outcome of fifty cases of nonalcoholic Wernicke's encephalopathy from a tertiary care hospital of a region with reported incidence of thiamine deficiency disorders.

MATERIALS AND METHODS

In a retrospective study, fifty adult cases of Wernicke's encephalopathy were analyzed. The diagnosis of Wernicke's encephalopathy was made according to the European federation of neurological societies guidelines 2010. Response to thiamine replacement and associated brain magnetic resonance imaging (MRI) findings were also considered as supportive evidence.

RESULTS

The mean age of patients was 50.38 years with 20 males and 30 females. The most common clinical manifestations were alteration in sensorium in 30 (60%), ataxia in 18 (36%), memory impairment in 15 (30%), nystagmus in 35 (70%), ophthalmoparesis in 11 (22%), and seizures in 4 (8%). A total of 42 patients had a history of recurrent vomiting. All patients had polished rice as their staple diet. Thirty-five patients had associated polyneuropathy and 15 had a gastrointestinal disorder. Twenty patients underwent MRI which showed both typical and atypical lesions. Majority of patients showed partial or complete response to intravenous thiamine. On discharge, the most common residual symptoms were lower limb weakness, ataxia, and memory impairment.

CONCLUSION

The study shows high incidence of nonalcoholic Wernicke's encephalopathy in the region with predominant causative factor being a thiamine deficient diet. Recurrent vomiting can be a prominent early symptom of thiamine deficiency and its recognition can help in the early diagnosis of Wernicke's encephalopathy and related thiamine deficiency disorders. Thiamine fortification of food should be done in areas with reported incidence of thiamine deficiency disorders.

A patient with Korsakoff syndrome of psychiatric and alcoholic etiology presenting as DSM-5 mild neurocognitive disorder

Background: Wernicke's encephalopathy (WE) and Korsakoff syndrome (KS) are underdiagnosed. The DSM-5 has raised the diagnostic threshold by including KS in the major neurocognitive disorders, which requires that the patient needs help in everyday activities. Methods: We report clinical, neuropsychological, and radiological findings from a patient who developed Wernicke-Korsakoff syndrome as a result of alcohol use and weight loss due to major depression. We assess the diagnosis in the context of the scientific literature on KS and according to the DSM-IV and the DSM-5. Results: The patient developed ataxia during a period of weight loss, thus fulfilling current diagnostic criteria of WE. WE was not diagnosed, but the patient partially improved after parenteral thiamine treatment. However, memory problems became evident, and KS was considered. In neuropsychological examination, the Logical Memory test and the Word List test were abnormal, but the Verbal Pair Associates test was normal (Wechsler Memory Scale-III). There were intrusions in the memory testing. The Wisconsin Card Sorting Test was broadly impaired, but the other test of executive functions (difference between Trail Making B and Trail Making A tests) was normal. There was atrophy of the mammillary bodies, the thalamus, the cerebellum, and in the basal ganglia but not in the frontal lobes. Diffusion tensor imaging showed damage in several tracts, including the uncinate fasciculi, the cinguli, the fornix, and the corona radiata. The patient remained independent in everyday activities. The patient can be diagnosed with KS according to the DSM-IV. According to the DSM-5, the patient has major neurocognitive disorders. Conclusions: Extensive memory testing is essential in the assessment of KS. Patients with a history of WE and typical clinical, neuropsychological, and radiological KS findings may be independent in everyday activities. Strict use of the DSM-5 may worsen the problem of Wernicke-Korsakoff syndrome underdiagnosis by excluding clear KS cases that do not have very severe functional impairment.

Epileptic seizures in nonalcoholic Wernicke's encephalopathy: a case report and literature review

Wernicke encephalopathy (WE) is characterized by eye signs, cerebellar dysfunction, and confusion. Epileptic seizures are rare in nonalcoholic WE. We reviewed the clinical, laboratory, radiological, and prognostic characteristics of nonalcoholic WE accompanied by epileptic seizures. We reported 1 case and searched similar cases using PubMed, WoK, Ovid, and Embase. WE was diagnosed according to dietary deficiencies, clinical symptoms and brain magnetic resonance imaging (MRI). We reviewed 13 patients (median age, 27 years; 5 men) with clear histories of thiamine deficiency and symptoms of typical WE. The type of epileptic seizures reported in the 13 cases reviewed was generically reported as seizures or convulsions in 4 patients; 7 patients had generalized tonic-clonic seizures, 1 partial seizure, and 1 generalized convulsive status epileptics. Two patients had epileptic seizures as the first symptom of WE. Laboratory tests mainly indicated metabolic acidosis and electrolyte disturbances. Electroencephalography may present as normal patterns, increased slow waves or epileptic discharge. Six patients had cortical lesions on brain MRI. These lesions were usually diffuse and band-like, and sometimes involved all lobes either symmetrically or asymmetrically, with the frontal lobe as the most susceptible area. All cortical lesions were accompanied by non-cortical lesions typical of WE. Brain MRI abnormalities, after thiamine treatment, mostly disappeared on follow-up MRIs. The patients had good prognoses. Only 1 patient had repeated seizures, and there were no comas or deaths. Patients with nonalcoholic WE accompanied by seizures are young and generally have good prognoses. Most patients experienced generalized convulsive seizures, which may have been related to abnormal cerebral cortical metabolism due to subacute thiamine deficiency.

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.

Cortical damage in Wernicke's encephalopathy with good prognosis: a report of two cases and literature review

Wernicke's encephalopathy (WE) is a thiamine deficiency-related condition, in which lesions are usually present in the periventricular and subcortical areas of the brain. However, lesions have also been found in atypical areas, such as the cerebral cortex. The present study summarizes the clinical outcomes and radiological features of WE with cortical impairment. We report two cases of cortical involvement in patients with WE, and review 22 similar cases from other reports. Among all 24 cases, 4 patients had a confirmed history of chronic daily alcohol abuse, and 19 of them had an identified causes of thiamine deficiency. 17 cases reported specific clinical information, among which 11 patients had symptoms of cortical impairment. 23 cases reported prognostic information at the end of treatment or at follow-up. The mortality rate was 26.1 % in our review. All patients had abnormal magnetic resonance imaging (MRI) signals or pathological findings in the bilateral cortex. Among patients with available MRI, 89.0 % had banding-like signs along the para-central sulcus. 13 cases underwent follow-up MRI examinations and 76.9 % displayed normal images. We suggest that WE with bilateral cortical involvement may have an acceptable prognosis, but that the mortality rate is higher than that among typical cases, especially if patients are not treated promptly and correctly. We identified the frontal and parietal lobes, especially around the central sulcus, to be the most susceptible areas, and suggest that the banding signs may be characteristic of WE. Persistent hyper-intensity on T2-weighted-fluid-attenuated inversion recovery, or gadolinium enhancement, may predict poor outcome.

Epileptic seizures as the first symptom of Wernicke's encephalopathy with cerebral cortical lesions

Wernicke's encephalopathy (WE) is acute metabolic disease of the central nervous system caused by deficiency of thiamine. Typical imaging findings are bilateral and symmetric signal in mammillary bodies, medial thalamus and periaqueductal gray. We present a 45-year-old man diagnosed for WE with two seizures and unconsciousness. The magnetic resonance imaging showed bilateral and symmetrical signal hyper-intensities in the frontal and parietal cortex, in addition to the classical MRI findings of WE. Cortical damage in WE is rare. The patient was improved significantly from unconsciousness to obeying commands and answering questions after 3days by thiamine supplementation. But the muscle strength and conscious state did not improve after 1year. This case report reminds us that we should take into account the possibility of WE when imaging shows cortical damage.

Non-alcoholic Korsakoff syndrome in psychiatric patients with a history of undiagnosed Wernicke's encephalopathy

Wernicke's encephalopathy is often undiagnosed, particularly in non-alcoholics. There are very few reports of non-alcoholic patients diagnosed with Korsakoff syndrome in the absence of a prior diagnosis of Wernicke's encephalopathy and no studies of diffusion tensor imaging in non-alcoholic Korsakoff syndrome. We report on three non-alcoholic psychiatric patients (all women) with long-term non-progressive memory impairment that developed after malnutrition accompanied by at least one of the three Wernicke's encephalopathy manifestations: ocular abnormalities, ataxia or unsteadiness, and an altered mental state or mild memory impairment. In neuropsychological examination, all patients had memory impairment, including intrusions. One patient had mild cerebellar vermis atrophy in MRI taken after the second episode of Wernicke's encephalopathy. The same patient had mild hypometabolism in the lateral cortex of the temporal lobes. Another patient had mild symmetrical atrophy and hypometabolism of the superior frontal lobes. Two patients were examined with diffusion tensor imaging. Reduced fractional anisotropy values were found in the corona radiata in two patients, and the uncinate fasciculus and the inferior longitudinal fasciculus in one patient. Our results suggest that non-alcoholic Korsakoff syndrome is underdiagnosed. Psychiatric patients with long-term memory impairment may have Korsakoff syndrome and, therefore, they should be evaluated for a history of previously undiagnosed Wernicke's encephalopathy.

Wernicke encephalopathy in pediatric neuro-oncology: presentation of 2 cases and review of literature

Wernicke encephalopathy represents a well-known entity characterized by a set of cognitive and neurologic alterations. Wernicke encephalopathy is rare and under-recognized in childhood and may be fatal. Few cases have been documented in pediatric oncology. We report on 2 Wernicke encephalopathy cases that occurred in children having a brain tumor. The diagnosis of Wernicke encephalopathy was suggested by clinical manifestations associated with the typical radiologic findings and a laboratory evidence of thiamine deficiency. No large series have been published to support the evidence that pediatric malignancies represent a demonstrated factor of increased risk to develop a Wernicke encephalopathy. Moreover, the diagnosis may be even more difficult in brain tumors, considering the overlapping symptoms and the risk of encephalopathy related to both the disease and the treatment. Wernicke encephalopathy should be considered in all children with cancer presenting a neurologic deterioration, mainly in brain tumors. An early diagnosis is imperative for a prompt therapy that might prevent or minimize the irreversible brain damage related to this condition.

MR imaging findings in alcoholic and nonalcoholic acute Wernicke's encephalopathy: a review

Wernicke's encephalopathy (WE) is a severe neurological syndrome caused by thiamine (vitamin B1) deficiency and clinically characterized by the sudden onset of mental status changes, ocular abnormalities, and ataxia. Apart from chronic alcoholism, the most common cause of WE, a lot of other conditions causing malnutrition and decreasing thiamine absorption such as gastrointestinal surgical procedures and hyperemesis gravidarum must be considered as predisposing factors. Due to its low prevalence and clinical heterogeneity, WE is often misdiagnosed, leading to persistent dysfunctions and, in some cases, to death. Nowadays, MR imaging of the brain, showing T2 and FLAIR hyperintensities in typical (thalami, mammillary bodies, tectal plate, and periaqueductal area) and atypical areas (cerebellum, cranial nerve nuclei, and cerebral cortex), is surely the most important and effective tool in the diagnostic assessment of WE. The aim of this paper is to propose a state of the art of the role of MR imaging in the early diagnosis of this complex disease.

Are brain and heart tissue prone to the development of thiamine deficiency?

Thiamine deficiency is a continuing problem leading to beriberi and Wernicke's encephalopathy. The symptoms of thiamine deficiency develop in the heart, brain and neuronal tissue. Yet, it is unclear how rapid thiamine deficiency develops and which organs are prone to development of thiamine deficiency. We investigated these issues in a thiamine deficient animal model. Twenty-four male Lewis rats were fed a thiamine deficient diet, which contained 0.04% of normal thiamine intake. Six control rats were fed 200 μg of thiamine per day. Every week a group of six rats on the thiamine-deficient diet was sacrificed and blood, urine and tissue were stored. Blood and tissue transketolase activity, thiamine and thiamine metabolites were measured and PCR of thiamine transporter-1 (ThTr-1) was performed. Transketolase activity was significantly reduced in red blood cells, liver, lung, kidney and spleen tissue after two weeks of thiamine deficient diet. In brain tissue, transketolase activity was not reduced after up to four weeks of thiamine deficient diet. The amount of thiamine pyrophosphate was also significantly conserved in brain and heart tissue (decrease of 31% and 28% respectively), compared to other tissues (decrease of ~70%) after four weeks of thiamine deficient diet. There was no difference between tissues in ThTr-1 expression after four weeks of thiamine deficient diet. Despite the fact that the heart and the brain are predilection sites for complications from thiamine deficiency, these tissues are protected against thiamine deficiency. Other organs could be suffering from thiamine deficiency without resulting in clinical signs of classic thiamine deficiency in beriberi and Wernicke's encephalopathy.

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.

Spectrum of MR imaging findings in Wernicke encephalopathy: are atypical areas of involvement only present in nonalcoholic patients?

BACKGROUND AND PURPOSE

Although MR imaging is considered the most effective method to confirm a diagnosis of WE, MR imaging studies designed to distinguish WE between NA and AL patients have yielded controversial results. The purpose of this study was to determine potential differences in MR imaging features between AL and NA patients with WE and to compare neurologic symptoms with MR imaging findings.

MATERIALS AND METHODS

This retrospective study included 24 consecutive patients (male/female, 15:9; mean age, 54 years) diagnosed with WE in a university hospital (AL = 13, NA = 11). Clinical manifestations and MR imaging findings between AL and NA patients were evaluated. Classic WE symptom triad and consciousness level and MR imaging findings were scored and compared with each other. Statistical analyses were performed with χ(2), Fisher exact, and Spearman tests.

RESULTS

No differences were observed regarding the areas of hyperintense signal intensity on FLAIR imaging and enhancement of the mammillary bodies between AL and NA patients (P > .05). Frequent sites of involvement were the medial thalami (86%), dorsal medulla (82%), tectal plate (77%), and the periaqueductal gray matter (75%). A positive association was found between the consciousness levels of the patients and the involvement of atypical sites (P = .01). Only 4 of the 24 patients (17%) had all 3 symptoms of the classic WE symptom triad.

CONCLUSIONS

MR imaging features of WE may not be different between AL and NA patients. The medulla is 1 of the most frequently involved sites, and consciousness level is also associated with atypical site involvement.

Thiamine in nutrition therapy

Clinicians involved with nutrition therapy traditionally concentrated on macronutrients and have generally neglected the importance of micronutrients, both vitamins and trace elements. Micronutrients, which work in unison, are important for fundamental biological processes and enzymatic reactions, and deficiencies may lead to disastrous consequences. This review concentrates on vitamin B(1), or thiamine. Alcoholism is not the only risk factor for thiamine deficiency, and thiamine deficiency is often not suspected in seemingly well-nourished or even overnourished patients. Deficiency of thiamine has historically been described as beriberi but may often be seen in current-day practice, manifesting as neurologic abnormalities, mental changes, congestive heart failure, unexplained metabolic acidosis, and so on. This review explains the importance of thiamine in nutrition therapy and offers practical tips on prevention and management of deficiency states.

Non-Alcoholic Wernicke Encephalopathy: MR Imaging and Review of the Literature

We describe a patient with non-alcoholic Wernicke's encephalopathy caused by long-term parenteral nutrition. The diagnosis is based on clinical and magnetic resonance findings. We also reviewed the literature review in typical and atypical findings at MR examination.

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.

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.

Clinical characteristics and MR imaging features of nonalcoholic Wernicke encephalopathy

BACKGROUND AND PURPOSE

Nonalcoholic Wernicke encephalopathy (WE) is prone to be underestimated in clinical practice. The purpose of this study was to improve its awareness and early accurate diagnosis.

MATERIALS AND METHODS

We conducted a retrospective review of the cases of 12 patients with nonalcoholic WE, consisting of clinical characteristics and MR imaging features as well as follow-up after administration of thiamine.

RESULTS

Patients with mild coma or lethargy (7/12) exhibited typical MR features of symmetric brain paraventricular damage. Patients without disturbances of consciousness or who only had drowsiness (3/12) exhibited a lesion of the periaqueductal area only. In addition to typical MR manifestations, symmetric cortical involvement was observed in 2 of 12 patients with deep coma. Gadolinium enhancement of the mammillary bodies was observed in 2 of 3 patients. No atrophy of the mammillary bodies and cerebellar vermis was found in any patients. Of 10 patients without deep coma and cortical damage, 2 missed the follow-up and 8, who recovered clinically, also showed accordant resolution of abnormal hyperintense signal intensity on T2-weighted and fluid-attenuated inversion recovery images within 2 weeks to 1 year after thiamine supplementation. Two patients with deep coma and cortical damage showed a poor prognosis:1 patient died 15 days after being diagnosed with WE, and the other entered a persistent vegetative state during a follow-up of 2 years.

CONCLUSION

Typical symmetric damage of the mammillary bodies and brain paraventricular regions may permit a specific diagnosis of nonalcoholic WE. In all patients, no atrophy of the mammillary bodies and cerebellar vermis was found. Cortical involvement in patients with nonalcoholic WE may be indicative of irreversible lesions and a poor prognosis.

MR imaging of metronidazole-induced encephalopathy: lesion distribution and diffusion-weighted imaging findings

BACKGROUND AND PURPOSE

MR imaging features of metronidazole-induced encephalopathy (MIE) have not been fully established. This study was undertaken to determine the topographic distributions and diffusion-weighted imaging (DWI) findings of MIE.

MATERIALS AND METHODS

We retrospectively evaluated the initial MR images (n = 7), including DWI (n = 5), and follow-up MR images (n = 4) after drug discontinuation in 7 patents with clinically diagnosed MIE. The topographic distributions of lesions were evaluated on MR images, and DWI signal intensities and apparent diffusion coefficient (ADC) values of the lesions were assessed.

RESULTS

MR images demonstrated bilateral symmetric T2 hyperintense lesions in the cerebellar dentate nucleus (n = 7), midbrain (n = 7), dorsal pons (n = 6), medulla (n = 4), corpus callosum (n = 4), and cerebral white matter (n = 1). Brain stem lesions involved the following: tectum (n = 5), tegmentum (n = 4), red nucleus (n = 3) of the midbrain, vestibular nucleus (n = 6), and a focal tegmental lesion involving the superior olivary nucleus (n = 6) and abducens nucleus (n = 4) of the pons and vestibular nucleus (n = 4) and inferior olivary nucleus (n = 1) of the medulla. DWI (n = 5) showed isointensity or hyperintensity of lesions, and the decreased ADC value was found only in the corpus callosum lesions (n = 2). All detected lesions were completely reversible at follow-up except for the single corpus callosum lesion with an initial low ADC value.

CONCLUSION

Brain lesions were typically located at the cerebellar dentate nucleus, midbrain, dorsal pons, medulla, and splenium of the corpus callosum. According to DWI, most of the lesions in MIE probably corresponded to areas of vasogenic edema, whereas only some of them, located in the corpus callosum, corresponded to cytotoxic edema.

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.

A theoretical argument for inherited thiamine insensitivity as one possible biological cause of familial alcoholism

Thiamine deficiency has been specifically linked to the development of Wernicke-Korsakoff syndrome (WK)--a degenerative brain disorder that is typically associated with alcoholic drinking. Alcoholism-related thiamine deficiency is a major cause of WK. However, an inherited abnormality in thiamine utilization has been identified in some WK patients that may predispose heavy drinkers to this severe neurological syndrome. Individuals who possess this variant require more thiamine throughout their lives to prevent them from experiencing thiamine deficiency. Recent prospective studies have implicated early childhood nutritional and environmental influences in the etiology of alcoholism in adults. These studies have suggested that developmental abnormalities involving brain white matter growth might precipitate the later development of alcoholism possibly by altering the emerging reward-related brain systems. Brain white matter growth is highly sensitive to nutritional deficiency (including thiamine deficiency) and oxidative injury, especially during the perinatal period. The proposed model of familial alcoholism hypothesizes that an inherited insensitivity to thiamine can precipitate brain abnormalities very early in life that will greatly increase the risk of developing alcoholism in adulthood. This paper offers a heuristic model of a possible mechanism by which both inherited and environmental factors related to thiamine utilization might coaggregate to cause alcoholism.

MRI findings of Wernicke encephalopathy revisited due to hunger strike

BACKGROUND AND PURPOSE

The purpose of this study was to determine the characteristic magnetic resonance imaging (MRI) findings among a group of patients who presented with Wernicke encephalopathy (WE) due to the neurological complications of a long-term hunger strike (HS).

METHODS

MRI studies also including the fluid-attenuated inversion recovery (FLAIR) sequence and diffusion-weighted imaging (DWI) of six male patients with WE aged from 25 to 38 years (mean age 31 years) were evaluated.

RESULTS

In all subjects, T2-weighted sequences, FLAIR and DWI revealed a signal hyperintensity within the posteromedial thalami and surrounding the third ventricle. In particular, on coronal images, the hyperintense areas around the third ventricle showed a suggestive "double wing" configuration. We observed an increased signal on proton-density and T2-weighted images in the mamillary bodies of three patients. Four patients demonstrated additional hyperintensities within the periaqueductal region and/or the tectal plate. At least one lesion area in five of six patients demonstrated contrast enhancement.

CONCLUSION

The consistent imaging findings of our study suggest that MRI is a reliable means of diagnosing WE. Acute WE is sometimes underdiagnosed, yet early diagnosis and treatment of WE is crucial in order to avoid persistent brain damage. MRI, including postcontrast T1-weighted imaging, DWI beneath standardized T2-weighted imaging, and FLAIR sequences may prove to be a valuable adjunct to clinical diagnosis and to provide additional information in acute and/or subacute WE.

Correlation of magnetic resonance images with neuropathology in acute Wernicke's encephalopathy

We correlated serial brain MRIs with neuropathological findings in a 16-year-old female whose autopsy was consistent with Wernicke's encephalopathy (WE). Diffusion-weighted imaging, diffusion coefficients mapping and neuropathology findings were suggested vasogenic edema in the periaqueductal and peri-the-fourth ventricular areas. This is the first documented case report to make this direct comparison. The characteristic WE changes in the mammillary body was also correlated with the findings of MRI with contrast enhancement. Bilateral cortical lesions revealed by MRI were atypical and rare in WE and were not evidenced by pathological changes.