Correlation of magnetic resonance images with neuropathology of irreversible metronidazole-induced encephalopathy: an autopsy case report.

BACKGROUND: Neurological symptoms and radiographic abnormalities may remain in a small proportion of patients with metronidazole-induced encephalopathy (MIE). Although experimental animal models of MIE have suggested a Wernicke's encephalopathy-like pathology, little is known about the histopathological features of MIE. Here we report the first autopsy case of irreversible MIE. CASE PRESENTATION: A 72-year-old Japanese woman with pancreatic neuroendocrine tumour and metastatic tumours in the liver developed intraabdominal bleeding from a hepatic abscess. She was administered metronidazole for 79 days (1.5 g/day), which caused dysarthria followed by hand tremor and altered mental status. Brain magnetic resonance imaging at the time of onset revealed hyperintensities in the deep white matter of the bilateral parietal lobes and splenium of the corpus callosum on diffusion-weighted imaging (DWI) with reduced apparent diffusion coefficient (ADC) values. Despite the improvement of dysarthria and hand tremor, her cognition remained affected even after the withdrawal of metronidazole. She died of pancreatic neuroendocrine tumour at the age of 74 years. Histopathological examinations of the brain confirmed a combination of severe demyelination and moderate axonal degeneration, which corresponded to the regions showing abnormal signal intensities on DWI with reduced ADC values. There were no pathological findings suggestive of Wernicke's encephalopathy in the brain. CONCLUSION: We have demonstrated the clinical, radiographic and histopathological aspects of irreversible MIE. Hyperintensities on DWI with reduced ADC values in affected regions may indicate a poor clinical prognosis due to irreversible pathological damage.

Stem Cell Transplant-Associated Wernicke Encephalopathy in a Patient with High-Risk Neuroblastoma.

Children undergoing intense cancer treatment frequently require total parenteral nutrition (TPN). Rarely, vitamins are removed due to hypersensitivity to the carrier vehicle in the formulation. We present the case of a 5-year-old patient with stage 4, high-risk neuroblastoma who developed altered mental status, ataxia, and tachycardia during consolidative autologous stem cell transplantation. Skin findings and brain MRI were consistent with thiamine (vitamin B1) deficiency and Wernicke encephalopathy. Vitamin B1 administration rapidly reversed all skin and neurologic symptoms. This case highlights the importance of close monitoring of micronutrients in pediatric patients receiving prolonged courses of chemotherapy and stem cell transplantation.

Neuropathology of alcoholism.

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

Associations between in vivo neuroimaging and postmortem brain cytokine markers in a rodent model of Wernicke's encephalopathy.

Thiamine (vitamin B1) deficiency, associated with a variety of conditions, including chronic alcoholism and bariatric surgery for morbid obesity, can result in the neurological disorder Wernicke's encephalopathy (WE). Recent work building upon early observations in animal models of thiamine deficiency has demonstrated an inflammatory component to the neuropathology observed in thiamine deficiency. The present, multilevel study including in vivo magnetic resonance imaging (MRI) and spectroscopy (MRS) and postmortem quantification of chemokine and cytokine proteins sought to determine whether a combination of these in vivo neuroimaging tools could be used to characterize an in vivo MR signature for neuroinflammation. Thiamine deficiency for 12days was used to model neuroinflammation; glucose loading in thiamine deficiency was used to accelerate neurodegeneration. Among 38 animals with regional brain tissue assayed postmortem for cytokine/chemokine protein levels, three groups of rats (controls+glucose, n=6; pyrithiamine+saline, n=5; pyrithiamine+glucose, n=13) underwent MRI/MRS at baseline (time 1), after 12days of treatment (time 2), and 3h after challenge (glucose or saline, time 3). In the thalamus of glucose-challenged, thiamine deficient animals, correlations between in vivo measures of pathology (lower levels of N-acetyle aspartate and higher levels of lactate) and postmortem levels of monocyte chemotactic protein-1 (MCP-1, also known as chemokine ligand 2, CCL2) support a role for this chemokine in thiamine deficiency-related neurodegeneration, but do not provide a unique in vivo signature for neuroinflammation.

[Wernicke encephalopathy accompanying linitis plastica]. / Wernicke-encephalopathia linitis plasticában.

Wernicke encephalopathy (or Wernicke-Korsakoff encephalopathy) is a rarely diagnosed neurological disorder, which is caused by vitamin B1 deficiency. In the classical form it is characterized by a typical triad (confusion, oculomotor disturbance and ataxia), however, in the majority of the cases only confusion is present. It can be frequently observed in subjects with chronic alcohol consumption, but it may accompany different pathological states of which end stage malignant diseases are the most importants, where confusion may have different backgrounds. The authors present the case of an old male patient with advanced gastric cancer recognised and treated vitamin B1 deficiency, and they draw attention to difficulties of the diagnosis of Wernicke's disease.

Isolated mammillary body involvement on MRI in Wernicke's encephalopathy.

A 48-year-old woman, with a remote history of gastric-banding as well as recent-onset post-prandial vomiting and excessive wine-drinking, was admitted with progressively-worsening gait incoordination. She showed gaze-evoked nystagmus and gait ataxia. Brain MRI revealed conspicuous, isolated, symmetrical T2/FLAIR-hyperintensities and gadolinium-enhancement of the mammillary bodies. Serum thiamine and folate were low. Following thiamine and folate replacement therapy, her ataxia resolved. Given the rising number of bariatric procedures, we discuss the importance of recognizing thiamine-deficiency in these patients. Additionally, while isolated involvement of the mammillary bodies is a rare finding in this disorder, we highlight radiologic changes that neurologists should recognize.

Evolution of abnormal eye movements in Wernicke's encephalopathy: correlation with serial MRI findings.

A 33-year-old woman with Wernicke's encephalopathy (WE) due to poor oral intake after allogeneic stem cell transplantation for acute myeloid leukemia showed a sequential development of bilateral gaze-evoked nystagmus (GEN), rightward gaze palsy, and upbeat nystagmus. Initial MRIs obtained when she had GEN only showed a lesion involving the medullary tegmentum, and follow-up MRIs revealed additional lesions in the pontine and midbrain tegmentum along with development of rightward gaze palsy, and finally bilateral medial thalamus lesions in association with upbeat nystagmus. The evolution of abnormal ocular motor findings and serial MRI changes in our patient with WE provide imaging evidence on relative vulnerability of the neural structures, and on the progression of lesions and ocular motor findings in thiamine deficiency.

Non-alcoholic acute Wernicke's encephalopathy: role of MRI in non typical cases.

AIM: Acute Wernicke's encephalopathy (WE) is a severe neurological disorder caused by thiamine deficiency, most commonly found in chronic alcoholics. It is not so easy to suspect acute WE when the clinical picture does not include all the typical symptoms and alcohol abuse is not reported. Three rare cases of Wernicke's encephalopathy (WE) in non-alcoholic patients are reported. CASES PRESENTATION: Two patients developed the disease following prolonged intravenous feeding, the third was carrying a gastric lymphoma. None of them presented with the classic clinical triad of WE (ophtalmoplegia/nystagmus, ataxia and consciousness disturbance), showing just one or two of the typical symptoms. Brain Magnetic Resonance Imaging (MRI) represented the key tool to suspect and define WE diagnosis, showing a picture characterized by bilaterally altered signal of the thalamic pulvinar, mesencephalic cup, mammillary bodies, periaqueductal grey matter and floor of fourth ventricle. All patients dramatically improved within 48 h after administration of thiamine. CONCLUSION: We emphasize that WE should be suspected in all patients showing typical MRI features presenting with at least one of the clinical triad of WE.

Immunohistochemical expression of proinflammatory cytokines IL-1ß, IL-6, TNF-α and involvement of COX-2, quantitatively confirmed by Western blot analysis, in Wernicke's encephalopathy.

Selective cerebral vulnerability is a major consequence of Wernicke's encephalopathy (WE), in which focal areas of the brain exhibit symmetrical profound neuronal loss and accompanying gliosis, occurring most frequently in diencephalic regions such as the thalamus and the mammillary bodies. Many processes have been proposed to explain the selective cerebral vulnerability and the focal neuronal cell death in Wernicke's encephalopathy. There are several mechanisms which are common to the pathophysiology of encephalopathies caused by thiamine deficiency (TD). Recently, emphasis is being placed on deficit in mitochondrial oxidative metabolism, oxidative/nitrosative stress, and the release of proinflammatory cytokines such as IL-1ß, IL-6, and tumor necrosis factor-α (TNF-α). Cyclooxygenase-2 (COX-2) plays major roles in regulating brain damage and inflammation. Here we present two fatal cases of non-alcohol associated WE. The immunohistochemical study revealed increased proinflammatory cytokine immunoreactivity in the neurons of the mammillary bodies and medial thalamus, and in the periaqueductal regions, compared with basal constitutive levels of expression in the frontal cortex. Positive (WE cases) and negative (immediate trauma deaths) case-controls were used to confirm the results. TD induced IL-1ß proteins weakly, while moderate increase was observed for TNF-α and IL-6. Immunofluorescence analysis by confocal microscopy confirmed the staining results for immunoreactivity in WE brains. Further, the induction of proinflammatory cytokine protein expression levels was quantified by Western blot analysis.

Basal Ganglia involvement in Wernicke encephalopathy: report of 2 cases.

We present the neuroimaging and clinical findings in 2 nonalcoholic adult patients with WE as assessed by MR imaging. The first patient presented with gait ataxia and changes in consciousness. MR imaging disclosed bilateral lesions in the dorsal striatum and cerebellum. None of the regions typically affected in WE were involved. The second patient showed symmetric lesions in the posterior putamen associated with the alterations frequently and infrequently found WE.

"Syndrome in syndrome": Wernicke syndrome due to afferent loop syndrome. Case report and review of the literature.

Wernicke syndrome is a rare neurological pathology due to a deficit in vitamin B1. The syndrome is common among alcohol abusers, patients with malignant tumor or gastrointestinal diseases, those who undergo hemodialysis or long-term peritoneal dialysis, pregnant women with hyperemesis, women who breast-feed, patients with hyperthyroidism or anorexia nervosa or gastric or jejunal-ileal bypass surgery for obesity, patients submitted to gastric surgery or prolonged total parenteral nutrition or prolonged intravenous therapy. We report a case of Wernicke syndrome due to afferent loop syndrome characterized by incoercible vomiting.

Imaging evaluation of demyelinating processes of the central nervous system.

Demyelinating processes involving the central nervous system have a variety of aetiologies and can be separated into primary and secondary demyelinating processes. The classic example of primary demyelination is multiple sclerosis. Secondary demyelination, where the aetiology is known, includes infectious, metabolic and toxic disease processes. The underlying component of all demyelinating disorders is damage to the myelin sheath and/or the oligodendrocyte, the cell forming the myelin sheath. These processes often have similar imaging findings, making knowledge of the patient's history, physical examination and laboratory evaluation imperative for developing a differential diagnosis. This pictorial essay provides a review of the imaging of these diverse disorders.

Wernicke's encephalopathy: an underrecognized and reversible cause of confusional state in cancer patients.

BACKGROUND: Wernicke's encephalopathy (WE) is a neurological emergency which presents with symptoms of confusion, ophthalmoplegia, and ataxia. Cancer patients are at high risk of this acute encephalopathy due to chronic malnutrition, chemotherapy-induced nausea and vomiting, and consumption of thiamine by rapidly growing tumors. A high index of suspicion is important as these critically ill patients may not present with the classic triad of symptoms. METHODS: This study is a retrospective review of 5 patients with WE identified at M.D. Anderson Cancer Center, Houston, Tex., USA. Detailed clinical histories, risk factors, imaging, and histopathological characteristics are described. RESULTS: Five WE patients were identified and all patients had rapidly growing cancers and were undergoing active treatment. All patients had poor nutritional status due to chronic nausea from chemotherapy. Three patients received bone marrow transplantation (BMT). Acute confusion was the most common symptom. Magnetic resonance imaging studies of the brain revealed restricted diffusion and fluid attenuation inversion recovery sequence hyperintensity in the medial thalami and periaqueductal gray matter. In 2 cases, WE was considered antemortem, and only 1 was empirically treated with thiamine, which rapidly reversed the imaging findings within 7 days and led to clinical improvement. Other cases were diagnosed at autopsy. CONCLUSION: It is crucial to consider WE in the differential diagnosis for all cancer patients with confusion. Cancer patients with malnutrition and patients with BMT are at high risk of developing WE. To prevent this devastating and often fatal neurologic complication, all cancer patients with confusion should be empirically treated with thiamine.

[Wernicke encephalopathy after subtotal gastrectomy for morbid obesity]. / Encéphalopathie de Gayet-Wernicke après gastrectomie partielle pour obésité morbide.

Wernicke's encephalopathy (WE) is one of the potential complications of obesity surgery. It is an acute neuropsychiatric syndrome resulting from thiamine deficiency often associated with repeated vomiting. The classic triad is frequently reported in these patients (optic neuropathy, ataxia and confusion), associated with uncommon features. Cerebral impairment affects the dorsal medial nucleus of the thalamus and the periaqueductal grey area, appearing on MRI, as hyperintense signals on T2, Flair and Diffusion weighted imaging. Early diagnosis and parenteral thiamine are required to decrease morbidity and mortality. We report a case of WE and Korsakoff's syndrome in a young obese patient after subtotal gastrectomy, who still has substantial sequelae. The contribution of MRI with diffusion-weighted imaging is illustrated. The interest of nutritional supervision in the first weeks and preventive thiamine supplementation in case of repeated vomiting are of particular importance in these risky situations.

Neurologic complications of gastric bypass surgery for morbid obesity.

BACKGROUND: The number of bariatric procedures is rapidly growing as the prevalence of obesity in the USA is increasing. Such procedures are not without complications, and those affecting the nervous system are often disabling and irreversible. We now describe our experience with these complications and review the pertinent literature. METHODS: We describe 26 patients with major neurologic conditions that seemed causally related to bariatric surgery encountered in the neurology service of a tertiary referral university medical center over a decade. RESULTS: The neurologic complications affected most regions of the nervous system: encephalopathy, optic neuropathy, myelopathy, polyradiculoneuropathy, and polyneuropathy. Myelopathy was the most frequent and disabling problem; symptoms began about a decade after surgery. Encephalopathy and polyradiculoneuropathy were acute and early complications. Except for vitamin B(12) and copper deficiencies in patients with myelopathy, we could not correlate specific nutritional deficiencies to the neurologic complications. All patients had multiple nutritional deficiencies, but their correction did not often yield dramatic results. The best result was achieved in one patient after surgical revision to reduce the bypassed jejunum. CONCLUSIONS: A wide spectrum of serious neurologic conditions may follow bariatric surgery. These complications may occur acutely or decades later.

[Unusual cortical compromise in a case of Wernicke's encephalopathy]. / Afectación cortical inusual en un caso de encefalopatía de Wernicke.

INTRODUCTION: Wernicke's encephalopathy (WE) is a metabolic disease due to thiamine deficiency; only 10% of cases are diagnosed pre-mortem. Symptoms of WE include ophthalmoplegia, nistagmus, ataxia and mental confusion; post-mortem examination shows characteristic symmetrical lesions in the mamillary bodies (MB), hypothalamus, thalamus, brain stem and cerebellum with spongiosis, demyelination, vascular proliferation and relative preservation of neurons. CASE REPORT: 50 years-old male with alcoholic hepatopathy and orthotopic hepatic transplant who suffered a second surgical intervention 10 days after due to problems in the biliar anastomosis. After this second surgery he showed an altered mental status, with fluctuating global confusion, disorientation and agitation. He died 52 days after the hepatic transplantation. Autopsy study showed bilateral broncopneumonia, brown discoloration of the MB and bilateral linear lesions in the cortex of both motor gyri, which histologically showed identical to the MB lesions with demyelination, capillary and glial proliferation and preservation of neurons. Alzheimer type II astrocytes were also found in basal nuclei and cortex. CONCLUSIONS: Typical WE lesions affect MB, hypothalamus, thalamus, brain stem and cerebellum; cortical lesions, when found, are due to hepatocerebral degeneration with Alzheimer type II astrocytes or to the citopathic effects of ethanol. In our case, cortical lesions were identical to the lesions found in MB, an extraordinary finding which we have not found reported in the literature.

Corpus callosum atrophy in Wernicke's encephalopathy.

BACKGROUND AND PURPOSE: Neuropathologic changes in Wernicke's encephalopathy (WE) involve variable brain structures. Corpus callosum involvement in WE, however, is largely unknown. The authors investigated the degree and the pattern of corpus callosum changes in WE according to the etiologies. METHODS: Nineteen patients with WE (between 34 and 81 years) and 19 age- and sex-matched control participants were included. The total cross-sectional callosal area and 5 callosal subregions (C1-C5) were measured by tracing outer margins in the midsagittal sections. Subregions were determined by placing radial dividers with 10 rays. The pixel numbers for corpus callosums were calculated, and the values obtained were adjusted for head size variations. RESULTS: The causes of WE were alcoholism (10), intestinal surgery (5), anorexia (3), and hyperemesis gravidarum (1). The mean size of the total corpus callosum was significantly reduced in alcoholic WE (P< .001; 527.8 +/- 70.8 mm2 for alcoholic WE; 664.6 +/- 58.1 mm2 for the corresponding controls), but not in nonalcoholic WE. In subregion analysis, prefrontal callosum (C2) atrophy was the most prominent in alcoholic WE. In contrast, only splenium (C5) was atrophied in nonalcoholic WE. The degree of atrophy did not change throughout the follow-up period (mean 5.3 weeks). CONCLUSION: This study suggests that the extent and location of corpus callosum atrophy differs between alcoholic WE and nonalcoholic WE, implying separate contribution of alcohol neurotoxicity and nutritional deficiency.