Wernicke encephalopathy: MR findings and clinical presentation

Wernicke encephalopathy (WE) is a severe neurological disorder caused by vitamin B1 deficiency. The aim of the study was to analyse MRI findings typical for this disease and to evaluate the significance of their correlations with clinical symptoms. Magnetic resonance images and clinical features of 12 patients with WE were analysed. The patients underwent MR imaging within 3-14 days after onset of clinical symptoms. In 7 of 12 patients MR imaging showed symmetrical diencephalic and midbrain lesions. Postcontrast T1-weighted images from 5 of 9 patients examined during the initial 6 days of acute WE showed a subtle enhancement of the mamillary bodies, the tectal plate, the periaqueductal area and the periventricular region of the third ventricle including the paramedian thalamic nuclei. In addition, T2-weighted and fluid-attenuated inversion recovery (FLAIR) images revealed hyperintense signals in these regions (except for 2 patients where the mamillary bodies were normal). Hyperintense lesions on T2-weighted images without any enhancement on postcontrast T1-weighted images were detected in 2 patients by MR imaging performed 11 or 14 days after onset of WE. Patients with hyperintensities on T2-weighted images of the periventricular region of the third ventricle and the paramedian thalamic nuclei had poor recovery from their mental dysfunction. The MR examination in case of WE shows a typical pattern of lesions in 58% of cases. Enhancement of the mamillary bodies, the periventricular region of the third ventricle including the paramedian thalamic nuclei, and the periaqueductal area on postcontrast T1-weighted images can be observed in the initial period after clinical onset of symptoms and are characteristic signs of the acute stage of WE. Hyperintense lesions in the periventricular region and the paramedian thalamic nuclei on T2-weighted and FLAIR images in the subacute stage of WE and enhancement on postcontrast T1-weighted images of the mamillary bodies and the paramedian thalamic nuclei are indicators of poor prognosis despite vitamin B1 substitution.

[Wernicke's encephalopathy induced by hyperemesis gravidarum (case report)]

One of the life-threatening complications of hyperemesis gravidarum is Wernicke's encephalopathy, the main etiological factor of which is a lack of thiamine (vitamin B1). Most frequently Wernicke's encephalopathy is found among persons suffering from excessive drinking. The aim of the report was to present a case of Wernicke's encephalopathy induced by hyperemesis gravidarum. The course of the disease, clinical signs, diagnostics, treatment and its results are presented. Also a review of the literature on Wernicke's encephalopathy secondary to hyperemesis gravidarum is introduced.

Diffusion weighted MR imaging of acute Wernicke's encephalopathy

We report a case of Wernicke's encephalopathy in which diffusion-weighted MR images demonstrated symmetrical hyperintense lesions in the paraventricular area of the third ventricles and medial thalami. Apparent diffusion coefficient mapping showed isointensity in the aforementioned areas. Diffusion-weighted MR images may provide evidence of vasogenic edema associated with thiamine deficiency, proven in the histopathology of experimental animals. In addition, diffusion-weighted MRI has many advantages over T2 or FLARE-weighted brain MRI in detecting structural and functional abnormalities in Wernicke's encephalopathy.

Wernicke encephalopathy: unusual findings in nonalcoholic patients

We report the unique findings on magnetic resonance imaging (MRI) in two cases of diet-related Wernicke encephalopathy (WE). There was no relation to alcohol in either case. The first patient presented with seizures and showed changes of WE on diffusion-weighted MRI with involvement of the motor strip. The second case illustrates extensive changes in the thalamus caused by WE, resulting in obstructive hydrocephalus requiring shunting.

The Royal College of Physicians report on alcohol: guidelines for managing Wernicke's encephalopathy in the accident and Emergency Department

The Royal College of Physicians (London) recently published its latest report on alcohol misuse entitled 'Alcohol - Can the NHS Afford It?'. Part of this document, encompassing our views, has made specific recommendations for the management of patients in the Accident and Emergency (A&E) Department who may possibly have, or are at risk of developing, Wernicke's encephalopathy. Patients showing evidence of chronic alcohol misuse and suspected of having a poor diet should be treated at the outset with B vitamins intravenously or intramuscularly, especially when the clinical signs are initially masked by drunkenness at presentation to the A&E Department. This commentary offers a review of the scientific foundations on which these recommendations have been made.

Proton MR spectroscopy of Wernicke encephalopathy

Two patients with acute thiamine deficiency were examined with thalamic single-voxel proton MR spectroscopy. T2-weighted images exhibited increased signal intensity. N-acetylaspartate (NAA)/creatine (Cr) ratios were low without detectable lactate. Owing to substantially decreased choline (Cho) T2, the Cho/Cr ratio was not decreased. After thiamine therapy, the NAA/Cr ratio increased, paralleling clinical improvement and reduction in the areas of signal-intensity changes.

[Value of MRI findings in Gayet-Wernicke encephalopathy]

Wernicke encephalopathy (Wernicke-Korsakoff encephalopathy) is related to thiamine deficiency. We report the MRI findings in four patients with visualization of bilateral and symmetrical hyperintense foci on T2W and FLAIR images involving the periaqueductal gray matter, the mamillary bodies and around the third ventricle. Diffusion weighted images obtained in two patients demonstrated mild hypersignal in the same areas. Contrast enhancement within the mamillary bodies was noted in one patient. Follow-up MRI obtained in three patients showed rapid regression of signal abnormalities without correlation with good clinical outcome.

Diffusion abnormalities in patients with Wernicke encephalopathy

Diffusion-weighted imaging (DWI) can help to diagnose acute ischemic stroke. Other nonischemic disorders may show abnormal signals with DWI. The authors report two cases of Wernicke encephalopathy with DWI signal changes in characteristic midline locations, one with reduction in apparent diffusion constant and one without. DWI abnormalities may suggest early thiamine deficiency and are useful in diagnosing Wernicke encephalopathy.

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.

Wernicke's encephalopathy due to hyperemesis gravidarum: an under-recognised condition

We present a case of a 25-year-old woman with drowsiness, nystagmus, severe ataxia and areflexia, which developed six weeks after admission to an obstetric clinic for hyperemesis gravidarum. She had been treated with intravenous dextrose and electrolyte solutions and antiemetics. Magnetic resonance imaging (MRI) performed on the fifth day of her neurologic symptoms showed increased intensity in both thalami, periaqueductal grey matter, the floor of the fourth ventricle and superior cerebellar vermis in T2 weighted and FLAIR images. Clinical signs and MRI findings were consistent with the diagnosis of Wernicke's encephalopathy. On the third day of thiamine replacement, neurologic signs improved dramatically In addition to our case, we review 29 previously reported cases of Wernicke's encephalopathy associated with hyperemesis gravidarum, and emphasize the importance of thiamine supplementation to women with prolonged vomiting in pregnancy especially if they are given intravenous or parenteral nutrition.

Diffusion-weighted MR in reversible wernicke encephalopathy

Diffusion-weighted images (DWI) of a patient with Wernicke encephalopathy were obtained during routine MR examination. Mammillary bodies were hyperintense on T2-weighted and enhanced on T1-weighted images; on DWI, a mild hyperintensity was noticed. Calculation of the apparent diffusion coefficient (ADC) demonstrated an increased diffusion on the affected regions; the hyperintensity on DWI was probably due to a "T2-shine-through" effect. These findings are consistent with the presence of extracellular oedema, without significant neuronal damage. The patient recovered promptly after thiamine administration, and MR alterations disappeared. The favourable evolution indicates that no relevant neuronal death occurred. This is consistent with DWI findings. DWI are more sensitive than ordinary T1- and T2-weighted images to neuronal irreversible damage, and may differentiate between neuronal necrosis and extracellular oedema in various brain pathologies. The demonstration of a limited neuronal damage may represent a favourable prognostic factor in patients with WE.

Thiamine deficiency and unexplained encephalopathy in hemodialysis and peritoneal dialysis patients

Patients with end-stage renal disease undergoing regular dialysis are prone to encephalopathy, but the cause is often unclear. Dialysis patients are at risk for thiamine deficiency, which may mimic many uremic complications, including encephalopathy. To determine whether unexplained encephalopathy in regular dialysis patients is associated with thiamine deficiency, we conducted a prospective study that enrolled 30 consecutive dialysis patients with altered mental status admitted to a referred hospital during a 1-year period. A complete history, physical and neurological examinations, laboratory investigations, and computed tomographic scans or magnetic resonance imaging of the brain were obtained for each subject. In 10 of the 30 patients, diagnoses remained obscure after the initial workup. Manifestations included confusion, chorea, acute visual loss, rapidly progressive dementia, myoclonus, convulsions, and coma. Intravenous thiamine was administered to these 10 patients. All 10 patients had thiamine deficiency confirmed by a marked response to thiamine supplementation and/or a low serum thiamine concentration (35.3 +/- 6.0 nmol/L; normal, >50 nmol/L). Nine patients recovered, but one patient failed to respond because of delayed treatment. We conclude that in regular dialysis patients, unexplained encephalopathy can be mainly attributed to thiamine deficiency. This condition is fatal if unrecognized and can be successfully treated with prompt thiamine replacement.

Wernicke's encephalopathy in a non-alcoholic man: case report and brief review

Wernicke's encephalopathy, a serious neurological disorder caused by thiamine deficiency, is most commonly found in chronic alcoholics. We present a typical case of Wernicke's encephalopathy in a non-alcoholic man. Our patient presented with altered mental status, slurred speech, fever, vomiting and headache of one-week duration. An infectious etiology of the symptoms was ruled out by spinal fluid cultures. The patient improved dramatically within 24 hours of administration of thiamine.

Wernicke's encephalopathy in patients with hyperemesis gravidarum

Our two patients presented with Wernicke's Encephalopathy (WE) resulting from prolonged hyperemesis gravidarum. This is an unusual cause of WE, a potentially fatal medical emergency due to thiamine deficiency. We discuss the clinical settings, presentation, diagnosis, neurophysiological and radiological findings, treatment and outcome of WE in these two cases and the neuropathologic correlation of this condition. We stress upon the importance of early diagnosis and prompt treatment of WE.

'Iatrogenic' Wernicke's encephalopathy in Japan

'Iatrogenic' Wernicke's encephalopathy has appeared to occur more frequently in Japan, probably induced by the change of our Japanese national health insurance policy in 1992. We report 4 nonalcoholic patients with such Wernicke's encephalopathy, which occurred during the early postoperative oral food intake period following intravenous nutrition without vitamin supplements. We analyzed the medical records of 4 patients, 3 men and 1 woman, aged between 55 and 71 years, who were admitted to our hospital between 1992 and 1995. Three patients underwent gastrointestinal surgery and 1 suffered chronic pyothorax. We diagnosed our patients as having Wernicke's encephalopathy based on typical neurological abnormalities, in addition to typical cranial magnetic resonance image findings, low serum vitamin B(1) levels, or both. Although all of the patients were treated with vitamin B(1) and showed some improvement, 1 patient developed Korsakoff syndrome, 2 made incomplete neurological recovery, and 1 died. We speculated that the body vitamin B(1) stores had been decreasing in our patients who did not receive any vitamin supplements during intravenous hyperalimentation or hydration. Subsequent administration of high calorie and high carbohydrate oral diets increased the demand for vitamin B(1), further depleting the vitamin stores, thereby causing 'iatrogenic' Wernicke's encephalopathy. The change of our national health insurance policy in 1992 discouraged the routine administration of vitamins, probably causing Wernicke's encephalopathy in our patients.