Is there a time window for MRI in Wernicke encephalopathy - a decade of experience from a tertiary hospital

Wernicke Encephalopathy Related to Hyperemesis Gravidarum: A Retrospective Study of 12 Cases

Objective: Wernicke encephalopathy (WE) related to hyperemesis gravidarum (HG) is a devastating neuropsychiatric syndrome that remains frequently undiagnosed in pregnant women. Although many cases have been published, more studies are required to establish guidelines for the early detection and treatment of this condition. Material and Methods: We conducted a retrospective study to analyze the available data concerning 12 cases of WE complicating HG in the Mother and Child Hospital's Obstetric Intensive Care Unit, belonging to Mohamed VI University Hospital of Marrakesh. Results: Twelve out of 76 HG admitted cases developed WE. Pregnant WE patients became depleted after 11 weeks of vomiting at median gestational weeks of 16.2. They had a severe weight loss of more than 5% of their body and had all presented prodromal signs of WE before the actual onset of the clinical triad. WE diagnosis was clinically made based on Caine's operational criteria as they allow early identification of the disease. A good tool that could also aid diagnosis is an encephalic MRI; however, it should not delay treatment with prompt administration of high doses of thiamin of > 500 mg/day. Chronic sequelae in this study occurred in 45.5% and death in one case. Conclusion: In HG, thiamin rapidly depletes which can lead to WE with adverse outcomes for the mother and fetus. Therefore, physicians must be vigilant in detecting early signs of WE to promptly provide a high dose of thiamin with targeted multimodal therapies as this could be lifesaving.

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.

Typical and atypical MRI abnormalities in Wernicke's encephalopathy: Correlation with blood vitamin B1 levels

PURPOSE

Clinical features of Wernicke's encephalopathy (WE) confirmed strictly through the low blood vitamin B1 (VB1) levels are limited. This study aimed to analyse magnetic resonance imaging (MRI) findings, and clinical characteristics, in patients with WE who have confirmed low blood VB1 levels.

METHODS

Clinical and laboratory records of 12 consecutive patients with WE admitted to our hospital during the past 11 years were reviewed. The WE diagnosis was confirmed based on low blood VB1 levels and the presence of at least one of the classical triad.

RESULTS

Ophthalmoplegia and nystagmus were recorded in 75% and 50% of the patients, respectively. Eleven of 12 patients presented with consciousness disturbance/memory loss. All patients experienced gait disturbances. Eight of the 12 patients exhibited MRI abnormalities at typical sites (the dorsal midbrain [n = 7], medial thalamus [n = 6], mammillary bodies [n = 5], and dorsal pons [n = 5]). Of the 12 patients, six showed abnormalities at atypical sites (the splenium of the corpus callosum [n = 4], fornix [n = 3], cerebral cortex [n = 2], cerebellar vermis [n = 2], and dorsal medulla [n = 1]). Patients with positive MRI abnormalities had significantly lower blood VB1 levels than those without abnormalities (9.5 vs. 16.0 ng/mL).

CONCLUSIONS

In cases of confirmed WE with low blood VB1 levels, the corpus callosum, fornix, and cerebral cortex were more frequently involved than in previous studies. MRI abnormalities at both typical and atypical sites were correlated with low blood VB1 levels in WE, suggesting that lower blood VB1 levels are associated with more severe brain damage in patients with WE.

Alcohol Use Disorder and Dementia: A Review

PURPOSE

By 2040, 21.6% of Americans will be over age 65, and the population of those older than age 85 is estimated to reach 14.4 million. Although not causative, older age is a risk factor for dementia: every 5 years beyond age 65, the risk doubles; approximately one-third of those older than age 85 are diagnosed with dementia. As current alcohol consumption among older adults is significantly higher compared to previous generations, a pressing question is whether drinking alcohol increases the risk for Alzheimer's disease or other forms of dementia.

SEARCH METHODS

Databases explored included PubMed, Web of Science, and ScienceDirect. To accomplish this narrative review on the effects of alcohol consumption on dementia risk, the literature covered included clinical diagnoses, epidemiology, neuropsychology, postmortem pathology, neuroimaging and other biomarkers, and translational studies. Searches conducted between January 12 and August 1, 2023, included the following terms and combinations: "aging," "alcoholism," "alcohol use disorder (AUD)," "brain," "CNS," "dementia," "Wernicke," "Korsakoff," "Alzheimer," "vascular," "frontotemporal," "Lewy body," "clinical," "diagnosis," "epidemiology," "pathology," "autopsy," "postmortem," "histology," "cognitive," "motor," "neuropsychological," "magnetic resonance," "imaging," "PET," "ligand," "degeneration," "atrophy," "translational," "rodent," "rat," "mouse," "model," "amyloid," "neurofibrillary tangles," "α-synuclein," or "presenilin." When relevant, "species" (i.e., "humans" or "other animals") was selected as an additional filter. Review articles were avoided when possible.

SEARCH RESULTS

The two terms "alcoholism" and "aging" retrieved about 1,350 papers; adding phrases-for example, "postmortem" or "magnetic resonance"-limited the number to fewer than 100 papers. Using the traditional term, "alcoholism" with "dementia" resulted in 876 citations, but using the currently accepted term "alcohol use disorder (AUD)" with "dementia" produced only 87 papers. Similarly, whereas the terms "Alzheimer's" and "alcoholism" yielded 318 results, "Alzheimer's" and "alcohol use disorder (AUD)" returned only 40 citations. As pertinent postmortem pathology papers were published in the 1950s and recent animal models of Alzheimer's disease were created in the early 2000s, articles referenced span the years 1957 to 2024. In total, more than 5,000 articles were considered; about 400 are herein referenced.

DISCUSSION AND CONCLUSIONS

Chronic alcohol misuse accelerates brain aging and contributes to cognitive impairments, including those in the mnemonic domain. The consensus among studies from multiple disciplines, however, is that alcohol misuse can increase the risk for dementia, but not necessarily Alzheimer's disease. Key issues to consider include the reversibility of brain damage following abstinence from chronic alcohol misuse compared to the degenerative and progressive course of Alzheimer's disease, and the characteristic presence of protein inclusions in the brains of people with Alzheimer's disease, which are absent in the brains of those with AUD.

Diagnosis and treatment of Wernicke's encephalopathy: A systematic literature review

BACKGROUND

Wernicke's encephalopathy (WE) is a serious neurological disorder that is underdiagnosed. Despite limited clinical guidelines, the standard use of intravenous (IV) thiamine is underutilized and remains an area of research deserving much attention.

OBJECTIVES

We conducted a systematic review using Medline, Embase, and CENTRAL databases to identify and summarize the literature on IV thiamine treatment in WE. Human studies with WE patients who received ≥100 mg of thiamine IV met inclusion criteria. Randomized controlled trials, cross-sectional studies, and case reports were included.

RESULTS

A total of 27 studies were included: 20 case reports, five retrospective studies, one prospective study and one randomized control trial. Of the case reports, 11 (55%) cases were female, and the average age of all cases was 45 years (SD = 15). The other seven studies included 688 patients; the average age was 52 years (SD = 9), and 266 (38.7%) were female. Among the case reports, neurological and clinical findings were used to diagnose WE in 16 (80%) cases. MRI was utilized to diagnose 15 (75%) cases. 500 mg IV thiamine TID was reported in 12 case reports (60%). 18 (90%) of case reports had partial or complete resolution of symptoms following IV thiamine.

CONCLUSION

IV thiamine can alleviate neurological symptoms, cognitive dysfunction, and brain imaging lesions associated with WE. We found key limitations in the evidence for IV thiamine and diagnostic standards for WE. Future targeted research should establish clear diagnostic and treatment guidelines for WE to prevent this serious condition from being underdiagnosed or undertreated.