Toxic encephalopathy is a term denoting brain injury and potentially life-threatening central nervous system (CNS) damage that can be induced by various toxic compounds. In the literature, the majority of patients suffer from this condition as a result of exposure to organic solvents or other lipophilic neurotoxins in the occupational setting [1] [2] [3], whereas several gases, chemotherapeutic drugs (such as L-asparagine, methotrexate), bacterial neurotoxins, recreational drugs, and ethanol can all be the underlying cause [4] [5] [6] [7]. Signs and symptoms of toxic encephalopathy appear in proportion to the amount of toxin that reaches the CNS, as well as the rate at which it damages the brain, thus a broad classification into acute and chronic forms has been made [1] [2] [3] [6]:

• Acute toxic encephalopathy is characterized by the development of acute alterations in consciousness, euphoria, seizures, stupor and in most severe cases, coma and even sudden death [1] [7]. Symptoms appear within days or weeks after the initial toxin exposure. Some of the most important toxins are gasses (such as carbon monoxide (CO), cyanide, and hydrogen sulfide) and heavy metals, both inorganic and organic (mercury, lead, and tin) [1] [2].
• Chronic toxic encephalopathy, on the other hand, causes a slowly progressive cognitive, intellectual, emotional and physical decline due to chronic exposure (months or even years) to a neurotoxic substance [1] [3] [6]. The severity of toxicity is divided into three stages. Initial symptoms (stage I) include mood changes and trouble concentrating, while attention and memory deficits, together with impaired learning, are typically encountered in stages II and III when a severe decline in psychomotor function is observed [1] [2] [3] [6].

In addition, toxic encephalopathy can also manifest through a specific subset of symptoms, such as cerebellar dysfunction (gait disturbances, ataxia, nystagmus, etc.) in methyl mercury (known as Minamata disease), methyl bromide, or organic tin toxicity, whereas chronic exposure to manganese produces Parkinson-like complaints accompanied by psychosis and various other neuropsychiatric symptoms, as it greatly interferes with the function of globus pallidus [1].

• Headache

  Persistent symptoms developed, an average, 16 years after exposure onset and included impaired memory (38), altered mood (21), imbalance (18), and headache (17). [ncbi.nlm.nih.gov]

  Chronic solvent inhalation, also called "chronic painter's disease", is associated with unsteadiness, headache, and psychological disturbances. This is attributed to cumulative slow damage to the lipophilic nervous system. [dizziness-and-balance.com]

• Confusion

  Encephalopathy causes confusion, abnormal thought processes, poor memory, hallucinations, and psychotic thinking. [healthcare-online.org]

  Alcohol intoxication can cause __ in the nervous system Euphoria, ataxia, confusion, coma, death Alcohol withdrawal can cause __ in the nervous system Delirium tremens (Tremor, hallucinations, confusion, autonomic features); Seizures within 48 hours Wernicke's [quizlet.com]

  There may be memory loss and confusion, loss of coordination and ataxia with a wobbling gait (walk), and confusion. Non-alcohol related causes can include AIDS, cancer, renal (kidney) dialysis, and hyperthyroidism (thyrotoxicosis). [emedicinehealth.com]

  If patients with hypoglycemia are given glucose at the first signs of encephalopathy (for example, irritability, mild confusion), most patients recover completely. [medicinenet.com]

  Wernicke's encephalopathy a neurological disorder characterized by confusion, apathy, drowsiness, ataxia of gait, nystagmus, and ophthalmoplegia; it is due to thiamine deficiency, usually from chronic alcohol abuse. [medical-dictionary.thefreedictionary.com]

• Tremor

  Two patients lost their consciousness, while two patients had typical extrapyramidal tremor symptoms. Further neurological examination revealed various degrees of muscle strength impairment in these patients. [ncbi.nlm.nih.gov]

  […] progressing to global dementia. hepatic encephalopathy a condition, usually occurring secondary to advanced liver disease, marked by disturbances of consciousness that may progress to deep coma (hepatic coma), psychiatric changes of varying degree, flapping tremor [medical-dictionary.thefreedictionary.com]

  […] encephalopathy is: Impaired ATTENTION (early finding in delirium, late finding in dementia) Symptoms of encephalopathy include: Hallucinations, delusions, agitation or lethargy; Irritation to light touch; Withdraw limbs unequally; Asterixis, myoclonus, tremor [quizlet.com]

  Significant tremors were present at rest, which increased on intention. There was lack of co-ordination of rapid alternating movements. The rest of the physical exam was non-contributory. [ijri.org]

  Other neurological symptoms may include myoclonus (involuntary twitching of a muscle or group of muscles), nystagmus (rapid, involuntary eye movement), tremor, muscle atrophy and weakness, dementia, seizures, and loss of ability to swallow or speak. [web.archive.org]

• Personality Change

  Depending on the type and severity of encephalopathy, common neurological symptoms are progressive loss of memory and cognitive ability, subtle personality changes, inability to concentrate, lethargy, and progressive loss of consciousness. [web.archive.org]

  Such injury may lead to chronic depression or other personality changes that can result in life-changing consequences. Even infants and children can suffer encephalopathy. [medicinenet.com]

• Ataxia

  A toxic encephalopathy characterized by depressed level of consciousness, marked irritability, and ataxia developed in seven children, 5 years of age and younger, following administration of an antiemetic combination of pentobarbital and pyrilamine maleate [ncbi.nlm.nih.gov]

  Need WIDE variations to change neuronal and glial dysfunction Because the brain is location-based, global disruption of metabolic homeostasis can result in: Behavior change, poor coordination, ataxia, confusion, seizures, stupor and coma; May be a lag [quizlet.com]

  Wernicke's encephalopathy a neurological disorder characterized by confusion, apathy, drowsiness, ataxia of gait, nystagmus, and ophthalmoplegia; it is due to thiamine deficiency, usually from chronic alcohol abuse. [medical-dictionary.thefreedictionary.com]

  In addition, toxic encephalopathy can also manifest through a specific subset of symptoms, such as cerebellar dysfunction (gait disturbances, ataxia, nystagmus, etc.) in methyl mercury (known as Minamata disease), methyl bromide, or organic tin toxicity [symptoma.com]

Acute toxic encephalopathy can often be fatal and brain damage caused by chronic exposure to neurotoxic substances may be irreversible in the absence of an early diagnosis, implying that clinical suspicion toward this syndrome must exist early on. Several reports have emphasized the vital role of a properly obtained patient history, which will assess the patient's occupancy, potential exposure to substances that may induce CNS-related symptoms (both in acute or chronic forms), as well as the course and progression of symptoms [1] [2] [3] [6]. Furthermore, a complete neurological examination, including the examination of cranial nerves, muscle tone, sensation, cerebellar function and evaluation of mental function should be subsequently conducted [1]. When there is a clinical suspicion of a primary CNS disorder, electroencephalography (EEG) and imaging studies of the brain must be carried out promptly [1] [3] [6]. Computed tomography (CT) is a useful initial method to rule out hemorrhage and other acute vascular incidents in the brain, while magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), functional MRI (fMRI), single photon emission tomography (SPECT) and positron emission tomography (PET) have all been described as important modalities in the evaluation of toxic encephalopathy [1] [3]. However, clinical criteria and findings obtained during history taking remain the cornerstone in diagnosing this condition.

• Triphasic Waves

  […] to diffuse slow activity (theta and delta), triphasic waves with bifrontal predominance may be registered. [neurologyindia.com]

RESULTS: Ninety-five patients started treatment, 84 patients had complete data. Treatment satisfaction was high. [ncbi.nlm.nih.gov]

Treatment [ edit ] Treatment is mainly for the symptoms that toxic encephalopathy brings upon victims, varying depending on how severe the case is. Diet changes and nutritional supplements may help some patients. [en.wikipedia.org]

Prognosis is usually good but fatalities and neurological deficits have been reported. We report here two infants with Margosa Oil poisoning presenting with encephalopathy. [ncbi.nlm.nih.gov]

Consequently, the prognosis varies from patient to patient and ranges from complete recovery to a poor prognosis that often leads to permanent brain damage or death. [medicinenet.com]

Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. [icd10coded.com]

Other alternative etiological entities were also excluded. Our findings indicate that long-term exposure to organic solvents may lead to a chronic brain syndrome. [ncbi.nlm.nih.gov]

Applicable To Toxic encephalitis Toxic metabolic encephalopathy Code First Code First Help Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. [icd10data.com]

Abstract A … More Psychosis possibly linked to an occupational disease: an e-patient’s participatory approach to consideration of etiologic factors Summary: The purpose of … More [psychoticdisorders.wordpress.com]

To be able to properly diagnose toxic encephalopathy, the professor believes doctors must have a specialized knowledge of the central and peripheral nervous systems, as well as toxicology, epidemiology and occupational medicine in order to understand [gesinjuryattorneys.com]

Page 69 - Epidemiology is defined as the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to control of health problems. ‎ [books.google.com]

These hydrocarbons have been confirmed in multiple human epidemiological studies to induce toxic encephalopathy among workers chronically exposed to levels near the OSHA PEL. [experttoxicologist.com]

"There is no epidemiological evidence or biological foundation for this allegation, yet I've seen a number of patients who believe that they have contracted Lyme disease from a sexual encounter," says Dr. Gary P. [sites.google.com]

Health science Providing basic knowledge of medical terminology, anatomy and physiology, and pathophysiology of diseases and conditions. [icd-10online.com]

The Centers for Medicare & Medicaid Services (CMS) assigns a lower severity to the nonspecific behavioral diagnosis of delirium than for the pathophysiological diagnosis of encephalopathy. [icd10monitor.com]

Encephalopathy may also develop in primary infections of CNS, as well as due to the prolonged effect of anesthetics and sedatives. [13] Pathophysiological mechanisms Pathophysiological mechanisms of encephalopathy are not fully understood. [neurologyindia.com]

[…] to WHO, the CTE can be classified into three stages ( Table I ): 1) ''organic affective syndrome'' (type I): characterized by depression, irritability, loss of interest in daily activities; course ranging from days to weeks with no sequels; unknown pathophysiology [scielo.br]

Can encephalopathy be prevented? Many cases of encephalopathy can be prevented. The key to prevention is to stop or limit the chance of developing any of the multitudes of causes of encephalopathy. [medicinenet.com]

Phase 3 monosialotetrahexosylganglioside Sodium 38 Monosialoganglioside(GM1) Preventing Neurotoxicity Induced by Cisplatin Contained Chemotherapy in NSCLC Patients Unknown status NCT01882621 Phase 3 Monosialoganglioside(GM1);normal saline 39 Evaluation [malacards.org]

According to the results of the study, conditions at work places ought to be changed in such a way that harmful exposure can be prevented in the future. [ncbi.nlm.nih.gov]

1. Kim Y, Kim JW. Toxic Encephalopathy. Saf Health Work. 2012;3(4):243-256.
2. Triebig G, Hallermann J. Survey of solvent related chronic encephalopathy as an occupational disease in European countries. Occupational and Environmental Medicine. 2001;58(9):575-581.
3. Ramos A, Jardim SR, Silva-Filho JF. Solvent-related chronic toxic encephalopathy as a target in the worker's mental health research. An Acad Bras Cienc. 2004;76(4):757-769.
4. Frantzeskaki F, Rizos M, Papathanassiou M, et al. L-asparaginase fatal toxic encephalopathy during consolidation treatment in an adult with acute lymphoblastic leukemia. Am J Case Rep. 2013;14:311-314.
5. Müller J1, Kralovánszky J, Adleff V, et al. Toxic encephalopathy and delayed MTX clearance after high-dose methotrexate therapy in a child homozygous for the MTHFR C677T polymorphism. Anticancer Res. 2008;28(5B):3051-3054.
6. Sørensen AM, Shapiro AU, Lund SP, Brun B, Rosenberg T, Lykke J. Toxic encephalopathy and noise-induced hearing loss. Noise Health. 2006;8(33):139-46.
7. Pourakbari B, Mamishi S, Kohan L, et al. Lethal toxic encephalopathy due to childhood shigellosis or Ekiri syndrome. J Microbiol Immunol Infect. 2012;45(2):147-150.