encephalopathy
(en-sef‵ă-lop'ă-thē 
)
[encephalo- + -pathy]
Generalized brain dysfunction marked by varying degrees of impairment of speech, cognition, orientation, and arousal. In mild instances, brain dysfunction may be evident only during specialized neuropsychiatric testing. In severe instances, e.g., the last stages of hepatic encephalopathy, the patient may be unresponsive even to unpleasant stimuli.
acute lead e.A syndrome seen mostly in children who have absorbed a large amount of lead. Initially there are clumsiness, vertigo, ataxia, headache, insomnia, restlessness, and irritability. As the syndrome progresses, vomiting, agitation, confusion, convulsions, and coma will occur. A sudden, marked increase in intracranial pressure accompanies these symptoms. Sequelae include permanent damage to the central nervous system, causing mental retardation, electroencephalogram abnormalities, cerebral palsy, and optic atrophy.
Exposure to lead must be discontinued. Corticosteroids and intravenous mannitol (20% solution) will relieve increased intracranial pressure. Lead can be removed from the body by giving dimercaprol (BAL) and calcium disodium edetate in carefully administered doses. Convulsions may be controlled with phenobarbital, hydantoin, or diazepam. Hydration should be maintained with intravenous administration of fluids; solutions containing sodium should be avoided. Oral fluids or food should not be given for at least 3 days.
asphyxial e.Hypoxic encephalopathy
ABBR: BSE
A progressive neurological disease of cattle, marked by spongelike changes in the brain and spinal cord and associated with rapid and fatal deterioration. SYN: mad cow disease.SEE: Creutzfeldt-Jakob disease; transmissible spongiform encephalopathy.
BSE is found in cattle that have been fed offal. A prion is thought to be the cause.
Because of the possible link between BSE and rapidly fatal neurological diseases in humans, many countries have banned the use of ruminant proteins in the preparation of cattle feed.
early infantile epileptic e. with suppression bursts
ABBR: EIEE
Ohtahara syndrome.epileptic e.Any of several severe forms of childhood epilepsy, in which recurrent seizures are associated with cognitive impairment. Examples include Dravet syndrome, Lennox-Gastaut syndrome, and Ohtahara syndrome.
hepatic e.Portal-systemic encephalopathy.
hypertensive e.The abrupt onset of headache and altered mental status that may occur with sudden and extreme elevations in blood pressure (usually diastolic pressures greater than 125 mm Hg). The altered mental states include irritability, confusion, convulsions, and /or coma. Nausea, vomiting, and visual disturbances are common. The symptoms resolve as the blood pressure is brought under control. Hypertensive encephalopathy is an emergency that requires immediate treatment, usually with intravenous medications. SYN: posthypoxia syndrome.
hyponatremic e.Headache, nausea, and vomiting, sometimes preceding seizures, lethargy, coma, and death in patients with low serum sodium levels, esp. hospitalized patients receiving hydration with dilute intravenous fluids.
hypoxic e.Neurological damage due to deprivation of oxygen and /or blood to the brain for several minutes. The damage may range from a transient loss of short-term memory to persistent vegetative coma. Many conditions can result in an oxygen deficiency in the brain, including carbon monoxide inhalation; cardiac arrest; hypotensive episodes of any kind, e.g., any form of shock; near-drowning; and suffocation. If patients are not rapidly revived and oxygenation restored, the hippocampus, and later the other cerebral structures, may be permanently injured and the patient may suffer irreversible brain damage. SYN: asphyxial encephalopathy; hypoxic-ischemic encephalopathy.
hypoxic-ischemic e.Hypoxic encephalopathy.
metabolic e.An alteration of brain function or consciousness due to failure of other internal organs. In the hospital, metabolic encephalopathy is among the most common causes of altered mental status. Renal failure, liver injury, electrolyte or acid-base abnormalities, hypoxia, hypercarbia, and inadequate brain perfusion caused by a failing heart are but some of the medical conditions that may produce treatable encephalopathies.
Confusion, irritability, seizures, and coma are common findings.
perinatal asphyxial e.Brain damage to newborn infants due to insufficient oxygenation and blood flow during delivery. Affected newborns have persistently low Apgar scores and need prolonged resuscitation; they are also affected by coma, lethargy, floppy musculature, seizures, acidosis, and /or absent reflexes. The long-term effects of asphyxia on the child include impairments of cognition, motor function, vision, and altered behavior.
ABBR: PSE
Brain dysfunction in patients with chronic liver disease and portal hypertension, in which chemicals that the liver normally detoxifies are shunted past it and left to circulate in the blood. Some patients are asymptomatic; others have mild impairments in memory, calculation, speech, affect, or judgment. Severely affected patients may lapse into coma. SYN: hepatic encephalopathy.SEE: asterixis.
e. of prematurity Encephalopathy resulting from damage to the periventricular cerebral white matter and to gray matter primarily in the cerebrum and diencephalon of very low birth weight infants. The disease also affects to a lesser extent the gray matter in the brain stem and cerebellum.
subcortical arteriosclerotic e.Binswanger disease.
transmissible spongiform e.Encephalopathy marked by rapidly developing dementia or the sudden onset of psychiatric illnesses, often with myoclonus, ataxia, and aphasia. Death may occur within months of onset. These illnesses are believed to be caused by prions. Examples include kuru, mad cow disease (bovine spongiform encephalopathy), and Creutzfeldt-Jakob disease.
SEE: under Wernicke, Carl.