• Safety and Health at Work
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• v.3 no.4
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• pp.243-256
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• 2012

This article schematically reviews the clinical features, diagnostic approaches to, and toxicological implications of toxic encephalopathy. The review will focus on the most significant occupational causes of toxic encephalopathy. Chronic toxic encephalopathy, cerebellar syndrome, parkinsonism, and vascular encephalopathy are commonly encountered clinical syndromes of toxic encephalopathy. Few neurotoxins cause patients to present with pathognomonic neurological syndromes. The symptoms and signs of toxic encephalopathy may be mimicked by many psychiatric, metabolic, inflammatory, neoplastic, and degenerative diseases of the nervous system. Thus, the importance of good history-taking that considers exposure and a comprehensive neurological examination cannot be overemphasized in the diagnosis of toxic encephalopathy. Neuropsychological testing and neuroimaging typically play ancillary roles. The recognition of toxic encephalopathy is important because the correct diagnosis of occupational disease can prevent others (e.g., workers at the same worksite) from further harm by reducing their exposure to the toxin, and also often provides some indication of prognosis. Physicians must therefore be aware of the typical signs and symptoms of toxic encephalopathy, and close collaborations between neurologists and occupational physicians are needed to determine whether neurological disorders are related to occupational neurotoxin exposure.

• Investigative Magnetic Resonance Imaging
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• v.20 no.3
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• pp.196-199
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• 2016

Viagra has been prescribed worldwide to treat men with erectile dysfunction. Clinical trials have shown that Viagra may cause various kinds of adverse effects include some central nervous system (CNS) adverse effects. Although extremely rare, toxic encephalopathy also can be one of those effects. This report presents a case of encephalopathy caused by Viagra in correlation with its radiologic findings. Its pharmacologic mechanism and potential effects on the biochemistry of the CNS are reviewed.

• Journal of Korean Neurosurgical Society
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• v.48 no.3
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• pp.301-304
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• 2010

Metronidazole is commonly used for brain abscess but is not well known for its neurotoxic complications. Metronidazole-induced encephalopathy (MIEP) is toxic encephalopathy associated with the use of metronidazole. We experienced a case of brain abscess which developed reversible severe MIEP during treatment period. Although MIEP occurs in typical locations, it is not easy to differentiate from other conditions such as cerebral infarction, demyelinating diseases and metabolic diseases. Neurosurgeons should be aware that severe MIEP can occur during the use of metronidazole though it is not common.

• Journal of the Korean neurological association
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• v.36 no.4
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• pp.322-324
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• 2018

Oculogyric crisis is an acute dystonia involving ocular muscles characterized by sustained conjugate upward or lateral deviation of the eyes. Metronidazole is a commonly used antimicrobial agent in treatment of anaerobic infections. However, its long-term use can cause toxic encephalopathy particularly in patients with hepatic dysfunction. Here, we describe a case of oculogyric crisis as a presenting manifestation of metronidazole-induced encephalopathy.

• Investigative Magnetic Resonance Imaging
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• v.22 no.3
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• pp.200-203
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• 2018

Metronidazole is an antimicrobial agent widely used for the treatment of anaerobic infection or antibiotics-associated diarrhea. It is generally thought to be safe, but can induce reversible toxic encephalopathy in the case of excessive or cumulative over-dose. Metronidazole-induced encephalopathy generally demonstrates the characteristic features of typical lesion location and bilaterality on magnetic resonance imaging (MRI). We report a case of metronidazole-induced encephalopathy with the involvement of asymmetric white matter. To our knowledge, only a few cases have been reported with respect to white matter lesion characteristics on MRI with diffusion-weighted images.

• The Journal of Internal Korean Medicine
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• v.42 no.5
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• pp.904-915
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• 2021

This study is a case report of Korean medicine treatment for a patient with quadriplegia and impaired cognition as neurological sequelae after ingestion of herbicides. A 59-year-old man with toxic encephalopathy and hypoxic encephalopathy after the ingestion of herbicides was treated with acupuncture, Hyulbuchuko-tang mixed with Ondam-tang-gami (血府逐瘀湯合溫膽湯加味), cupping, moxibustion, and rehabilitation. Clinical symptoms were measured with the Manual Muscle Test (MMT), Korean Mini Mental Status Exam (K-MMSE), Functional Independence Measure (FIM), and Modified Barthel Index (MBI). After three months of treatment, clinical symptoms improved. The motor function improved (MMT on both sides, Gr. 3+F/4G→Gr. 4-G~4G/4+G), cognition improved (K-MMSE, 13→21), and ADL (Activities of Daily Living) scores also improved (FIM 41→74; MBI 20→63). Korean medical treatment could effectively treat neurological sequelae after ingestion of herbicides in this case.

• Journal of The Korean Society of Clinical Toxicology
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• v.4 no.2
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• pp.131-136
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• 2006

Metronidazole is an antimicrobial drug widely used against various types of infectious agents, including protozoa, amoeba, Helicobacter pylori, and anaerobes. Metronidazole may produce some adverse effects on hematologic, immunologic, neurologic and other systems. We report a case of reversible metronidazole-induced encephalopathy. The toxic dose of metronidazole and the onset of encephalopathy were variable. Two patients showed abnormally high signal intensity in the bilateral dentate nucleus of cerebellum, and characteristic abnormalities were detected by brain magnetic resonance imaging (MRI) and T2-weighted images, fluid-attenuated inversion recovery images and/or diffusion weighted imaging (DWI). Discontinuation of metronidazole resulted in the improvement of the neurologic symptoms over a period of two to three weeks. We followed up the brain MRI with DWI in one case following obvious clinical improvement, and the previously detected lesion had disappeared.

• Journal of Korean Neurosurgical Society
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• v.58 no.2
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• pp.159-162
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• 2015

Neurological deficits after brain surgery are not uncommon, and correct and prompt differential diagnosis is essential to initiate appropriate treatment. We describe a patient suffering from loss of consciousness due to hyperammonemia, following valproic acid treatment after surgery for an unruptured cerebral aneurysm. A 57-year-old female patient underwent successful aneurysmal neck clipping to correct an unruptured aneurysm. Her postoperative course was good, and she received anti-epileptic therapy (valproic acid) and a soft diet. Within a few days the patient experienced mental deterioration. Her serum valproic acid reached toxic levels (149.40 mg/L), and serum ammonia was fifteen times the upper normal limit (553 mmol/L; normal range, 9-33 mmol/L). After discontinuation of valproic acid and with conservative treatment, the patient recovered without any complications. Valproate-induced hyperammonemic encephalopathy is an unusual but serious neurosurgical complication, and should not be disregarded as a possible cause of neurological deficits after neurovascular surgery. Early diagnosis is crucial, as discontinuation of valproic acid therapy can prevent serious complications, including death.

• Toxicological Research
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• v.33 no.4
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• pp.299-304
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• 2017

Thallium and its compounds are a class of highly toxic chemicals that cause wide-ranging symptoms such as gastrointestinal disturbances; polyneuritis; encephalopathy; tachycardia; skin eruptions; hepatic, renal, cardiac, and neurological toxicities; and have mutagenic and genotoxic effects. The present research aimed to evaluate the efficacy of the chelating agents deferasirox (DFX) and deferiprone (L1) in reducing serum and tissue thallium levels after the administration of thallium (III), according to two different dosing regimens, to several groups of Wistar rats for 60 days. It was hypothesized that the two chelators might be more efficient as a combined therapy than as monotherapies in removing thallium (III) from the rats' organs. The chelators were administered orally as either single or combined therapies for a period of 14 days. Serum and tissue thallium (III) and iron concentrations were determined by flame atomic absorption spectroscopy. Serum and tissue thallium (III) levels were significantly reduced by combined therapy with DFX and L1. Additionally, iron concentrations returned to normal levels and symptoms of toxicity decreased.

• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.99-99
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• 2003

To exhibit our clinical experience of diffusion-weighted (DW) MR imaging for various brain pathologies and to determine its role in characterizing brain pathologies in children. DW images in 177 children (M：F＝96：81, mean age, 4.7 years) with various brain pathologies were retrospectively collected over past 3 years. DW images (b value： 1000 s/mm) were reviewed along with corresponding apparent diffusion coefficient (ADC) maps. Brain pathologies included cystic or solid brain tumor (n = 55), cerebral infarct (n = 32), cerebritis with or without brain abscess (n = 21), metabolic or toxic brain disorder (n = 19), demyelinating disease (n = 16), hypoxic-ischemic encephalopathy (n = 16), intracerebral hemorrhage including traumatic brain lesion (n = 15), and posterior reversible leukoencephalopathy (n = 3). We reviewed whether DW images and ADCmaps contribute to further characterization of brain pathologies by defining a chronological age of lesions, the presence of cytotoxic edema in lesions, and the nature of cystic lesions.