Seizure
Encyclopedia
An epileptic seizure, occasionally referred to as a fit, is defined as a transient symptom of "abnormal excessive or synchronous neuronal activity in the brain". The outward effect can be as dramatic as a wild thrashing movement (tonic-clonic seizure) or as mild as a brief loss of awareness. It can manifest as an alteration in mental state
, tonic
or clonic movements, convulsion
s, and various other psychic symptoms (such as déjà vu
or jamais vu
). Sometimes it is not accompanied by convulsions but a full body "slump", where the person simply will lose control of their body and slump to the ground. The medical syndrome of recurrent, unprovoked seizures is termed epilepsy
, but seizures can occur in people who do not have epilepsy.
About 4% of people will have an unprovoked seizure by the age of 80 and the chance of experiencing a second seizure is between 30% and 50%. Treatment may reduce the chance of a second one by as much as half. Most single episode seizures are managed by primary care physicians (emergency or general practitioners), whereas investigation and management of ongoing epilepsy is usually by neurologists. Difficult-to-manage epilepsy may require consultation with an epileptologist
, a neurologist with an interest in epilepsy.
, myoclonic
, clonic, tonic, tonic–clonic, and atonic
seizures. A mixed seizure is defined as the existence of both generalized and partial seizures in the same patient.
Following standardization proposals published in 1970, outdated terms such as "petit mal", "grand mal", "Jacksonian", "psychomotor", and "temporal-lobe seizure" have fallen into disuse.
, visual changes, sensing/discharging of an unpleasant odor, a strange epigastric sensation, or a sensation of fear and total state of confusion. A seizure can last from a few seconds to status epilepticus
, a continuous group of seizures that is often life-threatening without immediate intervention. Therefore seizures are typically classified as motor, sensory
, autonomic
, emotion
al or cognitive. After the active portion of a seizure, there is typically a period referred to as postictal before a normal level of consciousness returns.
In some cases, the full onset of a seizure event is preceded by some of the sensations described above, called vertiginous epilepsy
. These sensations can serve as a warning to that a generalized tonic–clonic seizure is about to occur. These warning sensations are cumulatively called an aura
and are due to a focal seizure.
Some patients are able to tell when a seizure is about to happen. Some symptoms experienced by the person before a seizure may include dizziness, lightheadedness, tightening of the chest, and some experience things in slow-motion just prior to the seizure. Symptoms experienced by a person during a seizure depend on where in the brain the disturbance in electrical activity occurs. Partial and frontal seizures and focal epileptic discharges tend to happen more during sleep than during wakefulness. In contrast, psychogenic nonepileptic seizures are rare between midnight and 6 a m. and never occur during sleep. Generalized epilepsy but not focal epilepsy is higher in the morning probably reflecting a diurnal variation in cortical excitability. A person having a tonic–clonic seizure may cry out, lose consciousness and fall to the ground, and convulse, often violently. A person having a complex partial seizure
may appear confused or dazed and will not be able to respond to questions or direction. Some people have seizures that are not noticeable to others. Sometimes, the only clue that a person is having an absence seizure
is rapid blinking, extreme confusion for a few seconds or sometimes into hours.
Causes of provoked seizures include:
Some medications produce an increased risk of seizures and electroconvulsive therapy
(ECT) deliberately sets out to induce a seizure for the treatment of major depression. Many seizures have unknown causes.
Seizures which are provoked are not associated with epilepsy, and people who experience such seizures are normally not diagnosed with epilepsy. However, the seizures described above resemble those of epilepsy both outwardly, and on EEG
testing.
Seizures can occur after a subject witnesses a traumatic event. This type of seizure is known as a psychogenic non-epileptic seizure and is related to posttraumatic stress disorder.
. It is important to distinguish primary epileptic seizures from secondary causes. Blood tests, lumbar puncture
or toxicology screening can be helpful in specific circumstances suggestive of an underlying cause like alcohol or benzodiazepine withdrawal, meningitis
or drug overdose
, but there is insufficient evidence to support their routine use in the work-up of an adult with an apparently unprovoked first seizure. A 2007 review recommends an electroencephalogram and brain imaging with CT scan or MRI scan in the work-up. MRI is more sensitive in a first apparently unprovoked seizure.
following a seizure. In this state they are drowsy and often confused. There may be signs of other injuries. A small study found that finding a bite to the side of the tongue was very helpful when present: while only a quarter of those with seizures had such a bite (sensitivity of 24%), the finding was very specific for seizures, with only 1% due to other causes (specificity of 99%).
have quantified the role of an elevated serum prolactin
.
The first meta-analysis found that:
"If a serum prolactin concentration is greater than three times the baseline when taken within one hour of syncope, then in the absence of test "modifiers":
The second meta-analysis found:
The serum prolactin level is less sensitive for detecting partial seizures.
examination without a clinical presentation is called subclinical seizure
. They can identify background epileptogenic activity, as well as help identify causes of seizures.
As seizures have a broad differential diagnosis
, it is common for patients to be simultaneously investigated for cardiac and endocrine causes. Checking glucose
levels, for example, is a mandatory action in the management of seizures as hypoglycemia
may cause seizures, and failure to administer glucose would be harmful to the patient. Other causes typically considered are syncope and cardiac arrhythmias, and occasionally panic attack
s and cataplexy
. In addition, 5% of patients with a positive tilt table test
may have seizure-like activity that seems to be due to cerebral hypoxia
. For more information, see non-epileptic seizures
.
, migraine headaches, and strychnine poisoning.
.
A seizure longer than five minutes is a medical emergency. Caregivers may carry medicine.
. This may be repeated if there is no effect after 10 minutes. If there is no effect after two doses, barbiturate
s or propofol
may be used. Ongoing medication is not typically needed after a first seizure and is generally only recommended after a second has occurred or those with structural lesions in the brain.
can be trained to summon help or ensure personal safety when a seizure occurs. These are not suitable for everybody. Rarely, a dog may develop the ability to sense a seizure before it occurs. Helmets may be used to provide protection of the head during a seizure.
. In those with a status epilepticus mortality is between 10 and 40%.
in 400B.C. as "the sacred disease".
Mental state
* In psychology, mental state is an indication of a person's mental health**Mental status examination, a structured way of observing and describing a patient's current state of mind...
, tonic
Tonic (physiology)
Tonic in physiology refers to a physiological response which is slow, and may be graded. This term is typically used in opposition to a fast response...
or clonic movements, convulsion
Convulsion
A convulsion is a medical condition where body muscles contract and relax rapidly and repeatedly, resulting in an uncontrolled shaking of the body. Because a convulsion is often a symptom of an epileptic seizure, the term convulsion is sometimes used as a synonym for seizure...
s, and various other psychic symptoms (such as déjà vu
Déjà vu
Déjà vu is the experience of feeling sure that one has already witnessed or experienced a current situation, even though the exact circumstances of the prior encounter are uncertain and were perhaps imagined...
or jamais vu
Jamais vu
In psychology, jamais vu is the phenomenon of experiencing a situation that one recognises but that nonetheless seems very unfamiliar.-Linguistics:...
). Sometimes it is not accompanied by convulsions but a full body "slump", where the person simply will lose control of their body and slump to the ground. The medical syndrome of recurrent, unprovoked seizures is termed epilepsy
Epilepsy
Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
, but seizures can occur in people who do not have epilepsy.
About 4% of people will have an unprovoked seizure by the age of 80 and the chance of experiencing a second seizure is between 30% and 50%. Treatment may reduce the chance of a second one by as much as half. Most single episode seizures are managed by primary care physicians (emergency or general practitioners), whereas investigation and management of ongoing epilepsy is usually by neurologists. Difficult-to-manage epilepsy may require consultation with an epileptologist
Epileptologist
An epileptologist is a neurologist who specializes in the treatment of epilepsy. Epileptologists are experts in seizures and seizure disorers, anticonvulsants, and special situations involving seizures, such as cases in which all treatment intended to stop seizures has failed and epilepsy in...
, a neurologist with an interest in epilepsy.
Classification
Clinicians organize different types of seizure according to whether the source of the seizure within the brain is localized (partial- or focal-onset seizures) or distributed (generalized seizures). Partial seizures are further divided on the extent to which consciousness is affected (simple partial seizures and complex partial seizures). If consciousness is unaffected, then it is a simple partial seizure; otherwise it is a complex partial seizure. A partial seizure may spread within the brain—a process known as secondary generalization. Generalized seizures are divided according to the effect on the body, but all involve loss of consciousness. These include absenceAbsence seizure
Absence seizures are one of several kinds of seizures. These seizures are sometimes referred to as petit mal seizures ....
, myoclonic
Myoclonus
Myoclonus is brief, involuntary twitching of a muscle or a group of muscles. It describes a medical sign and, generally, is not a diagnosis of a disease. Brief twitches are perfectly normal. The myoclonic twitches are usually caused by sudden muscle contractions; they also can result from brief...
, clonic, tonic, tonic–clonic, and atonic
Atonic seizure
Atonic seizures , are a type of seizure. They consist of a brief lapse in muscle tone that are caused by temporary alterations in brain function. The seizures are brief - usually less than fifteen seconds. They begin in childhood and may persist into adulthood...
seizures. A mixed seizure is defined as the existence of both generalized and partial seizures in the same patient.
Following standardization proposals published in 1970, outdated terms such as "petit mal", "grand mal", "Jacksonian", "psychomotor", and "temporal-lobe seizure" have fallen into disuse.
Signs and symptoms
The signs and symptoms of seizures vary depending on the type. Seizures may cause involuntary changes in body movement or function, sensation, awareness, or behavior. Seizures are often associated with a sudden and involuntary contraction of a group of muscles and loss of consciousness. However, a seizure can also be as subtle as a fleeting numbness of a part of the body, a brief or long term loss of memoryMemory
In psychology, memory is an organism's ability to store, retain, and recall information and experiences. Traditional studies of memory began in the fields of philosophy, including techniques of artificially enhancing memory....
, visual changes, sensing/discharging of an unpleasant odor, a strange epigastric sensation, or a sensation of fear and total state of confusion. A seizure can last from a few seconds to status epilepticus
Status epilepticus
Status epilepticus is a life-threatening condition in which the brain is in a state of persistent seizure. Definitions vary, but traditionally it is defined as one continuous unremitting seizure lasting longer than 5 minutes, or recurrent seizures without regaining consciousness between seizures...
, a continuous group of seizures that is often life-threatening without immediate intervention. Therefore seizures are typically classified as motor, sensory
Sensory neuron
Sensory neurons are typically classified as the neurons responsible for converting external stimuli from the environment into internal stimuli. They are activated by sensory input , and send projections into the central nervous system that convey sensory information to the brain or spinal cord...
, autonomic
Autonomic nervous system
The autonomic nervous system is the part of the peripheral nervous system that acts as a control system functioning largely below the level of consciousness, and controls visceral functions. The ANS affects heart rate, digestion, respiration rate, salivation, perspiration, diameter of the pupils,...
, emotion
Emotion
Emotion is a complex psychophysiological experience of an individual's state of mind as interacting with biochemical and environmental influences. In humans, emotion fundamentally involves "physiological arousal, expressive behaviors, and conscious experience." Emotion is associated with mood,...
al or cognitive. After the active portion of a seizure, there is typically a period referred to as postictal before a normal level of consciousness returns.
In some cases, the full onset of a seizure event is preceded by some of the sensations described above, called vertiginous epilepsy
Vertiginous epilepsy
Vertiginous epilepsy is infrequently the first symptoms of a seizure. When it occurs there is a movement sensation that lasts for a few seconds before full seizure activity. The movement activity is either of the body moving away from the side of the brain lesion or of the environment in the...
. These sensations can serve as a warning to that a generalized tonic–clonic seizure is about to occur. These warning sensations are cumulatively called an aura
Aura (symptom)
An aura is a perceptual disturbance experienced by some migraine sufferers before a migraine headache, and the telltale sensation experienced by some people with epilepsy before a seizure. It often manifests as the perception of a strange light, an unpleasant smell or confusing thoughts or...
and are due to a focal seizure.
Some patients are able to tell when a seizure is about to happen. Some symptoms experienced by the person before a seizure may include dizziness, lightheadedness, tightening of the chest, and some experience things in slow-motion just prior to the seizure. Symptoms experienced by a person during a seizure depend on where in the brain the disturbance in electrical activity occurs. Partial and frontal seizures and focal epileptic discharges tend to happen more during sleep than during wakefulness. In contrast, psychogenic nonepileptic seizures are rare between midnight and 6 a m. and never occur during sleep. Generalized epilepsy but not focal epilepsy is higher in the morning probably reflecting a diurnal variation in cortical excitability. A person having a tonic–clonic seizure may cry out, lose consciousness and fall to the ground, and convulse, often violently. A person having a complex partial seizure
Complex partial seizure
A complex partial seizure is an epileptic seizure that is associated with bilateral cerebral hemisphere involvement and causes impairment of awareness or responsiveness, i.e. loss of consciousness.-Presentation:...
may appear confused or dazed and will not be able to respond to questions or direction. Some people have seizures that are not noticeable to others. Sometimes, the only clue that a person is having an absence seizure
Absence seizure
Absence seizures are one of several kinds of seizures. These seizures are sometimes referred to as petit mal seizures ....
is rapid blinking, extreme confusion for a few seconds or sometimes into hours.
Causes
Unprovoked seizures are often associated with epilepsy and related seizure disorders.Causes of provoked seizures include:
- sleep deprivationSleep deprivationSleep deprivation is the condition of not having enough sleep; it can be either chronic or acute. A chronic sleep-restricted state can cause fatigue, daytime sleepiness, clumsiness and weight loss or weight gain. It adversely affects the brain and cognitive function. Few studies have compared the...
- cavernoma or cavernous malformation is a treatable medical condition that can cause seizures, headaches, and brain hemorrhages. An MRI can quickly confirm or reject this as a cause.
- arteriovenous malformationArteriovenous malformationArteriovenous malformation or AVM is an abnormal connection between veins and arteries, usually congenital. This pathology is widely known because of its occurrence in the central nervous system, but can appear in any location. An arteriovenous malformation is a vascular anomaly. It is a...
(AVM) is a treatable medical condition that can cause seizures, headaches, and brain hemorrhages. An MRI can quickly confirm or reject this as a cause. - head injuryTraumatic brain injuryTraumatic brain injury , also known as intracranial injury, occurs when an external force traumatically injures the brain. TBI can be classified based on severity, mechanism , or other features...
may cause non-epileptic post-traumatic seizures or post-traumatic epilepsyPost-traumatic epilepsyPost-traumatic epilepsy is a form of epilepsy that results from brain damage caused by physical trauma to the brain . A person with PTE suffers repeated post-traumatic seizures more than a week after the initial injury...
, in which the seizures chronically recur. - intoxicationDrug overdoseThe term drug overdose describes the ingestion or application of a drug or other substance in quantities greater than are recommended or generally practiced...
with drugs, for example aminophyllineAminophyllineAminophylline is a bronchodilator. It is a compound of the bronchodilator theophylline with ethylenediamine in 2:1 ratio. The ethylenediamine improves solubility, and the aminophylline is usually found as a dihydrate-Properties:...
or local anaesthetics - normal doses of certain drugs that lower the seizure threshold, such as tricyclic antidepressantTricyclic antidepressantTricyclic antidepressants are heterocyclic chemical compounds used primarily as antidepressants. The TCAs were first discovered in the early 1950s and were subsequently introduced later in the decade; they are named after their chemical structure, which contains three rings of atoms...
s - infectionInfectionAn infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
, such as encephalitisEncephalitisEncephalitis is an acute inflammation of the brain. Encephalitis with meningitis is known as meningoencephalitis. Symptoms include headache, fever, confusion, drowsiness, and fatigue...
or meningitisMeningitisMeningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs... - feverFeverFever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
leading to febrile convulsions (but see above) - metabolicMetabolismMetabolism is the set of chemical reactions that happen in the cells of living organisms to sustain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories...
disturbances, such as hypoglycaemia, hyponatremiaHyponatremiaHyponatremia is an electrolyte disturbance in which the sodium concentration in the serum is lower than normal. In the vast majority of cases, hyponatremia occurs as a result of excess body water diluting the serum sodium and is not due to sodium deficiency. Sodium is the dominant extracellular...
or hypoxiaHypoxia (medical)Hypoxia, or hypoxiation, is a pathological condition in which the body as a whole or a region of the body is deprived of adequate oxygen supply. Variations in arterial oxygen concentrations can be part of the normal physiology, for example, during strenuous physical exercise... - withdrawalWithdrawalWithdrawal can refer to any sort of separation, but is most commonly used to describe the group of symptoms that occurs upon the abrupt discontinuation/separation or a decrease in dosage of the intake of medications, recreational drugs, and alcohol...
from drugs (anticonvulsantAnticonvulsantThe anticonvulsants are a diverse group of pharmaceuticals used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of bipolar disorder, since many seem to act as mood stabilizers, and in the treatment of neuropathic pain. The goal of an...
s, antidepressantAntidepressantAn antidepressant is a psychiatric medication used to alleviate mood disorders, such as major depression and dysthymia and anxiety disorders such as social anxiety disorder. According to Gelder, Mayou &*Geddes people with a depressive illness will experience a therapeutic effect to their mood;...
s, and sedativeSedativeA sedative or tranquilizer is a substance that induces sedation by reducing irritability or excitement....
s such as alcoholEthanolEthanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
, barbiturates, and benzodiazepines,) - space-occupying lesions in the brain (abscessAbscessAn abscess is a collection of pus that has accumulated in a cavity formed by the tissue in which the pus resides due to an infectious process or other foreign materials...
es, tumorTumorA tumor or tumour is commonly used as a synonym for a neoplasm that appears enlarged in size. Tumor is not synonymous with cancer...
s) - seizures during (or shortly after) pregnancy can be a sign of eclampsiaEclampsiaEclampsia , an acute and life-threatening complication of pregnancy, is characterized by the appearance of tonic-clonic seizures, usually in a patient who had developed pre-eclampsia...
. - seizures in a person with hydrocephalusHydrocephalusHydrocephalus , also known as "water in the brain," is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid in the ventricles, or cavities, of the brain. This may cause increased intracranial pressure inside the skull and progressive enlargement of the head,...
may indicate severe shuntShuntShunt may refer to:* Shunt - a hole or passage allowing fluid to move from one part of the body to another* Shunt - a device allowing electrical current to pass around a point in a circuit...
failure. - binaural beat brainwave entrainment may trigger seizures in both epileptics and non-epileptics
- haemorrhagic strokeStrokeA stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
can occasionally present with seizures, embolicEmbolismIn medicine, an embolism is the event of lodging of an embolus into a narrow capillary vessel of an arterial bed which causes a blockage in a distant part of the body.Embolization is...
strokes generally do not (though epilepsy is a common later complication); cerebral venous sinus thrombosisCerebral venous sinus thrombosisCerebral venous sinus thrombosis is a rare form of stroke that results from thrombosis of the dural venous sinuses, which drain blood from the brain. Symptoms may include headache, abnormal vision, any of the symptoms of stroke such as weakness of the face and limbs on one side of the body, and...
, a rare type of stroke, is more likely to be accompanied by seizures than other types of stroke - multiple sclerosisMultiple sclerosisMultiple sclerosis is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring as well as a broad spectrum of signs and symptoms...
sufferers may rarely experience seizures
Some medications produce an increased risk of seizures and electroconvulsive therapy
Electroconvulsive therapy
Electroconvulsive therapy , formerly known as electroshock, is a psychiatric treatment in which seizures are electrically induced in anesthetized patients for therapeutic effect. Its mode of action is unknown...
(ECT) deliberately sets out to induce a seizure for the treatment of major depression. Many seizures have unknown causes.
Seizures which are provoked are not associated with epilepsy, and people who experience such seizures are normally not diagnosed with epilepsy. However, the seizures described above resemble those of epilepsy both outwardly, and on EEG
EEG
EEG commonly refers to electroencephalography, a measurement of the electrical activity of the brain.EEG may also refer to:* Emperor Entertainment Group, a Hong Kong-based entertainment company...
testing.
Seizures can occur after a subject witnesses a traumatic event. This type of seizure is known as a psychogenic non-epileptic seizure and is related to posttraumatic stress disorder.
Diagnosis
Only about 25 percent of people who have a seizure or develop status epilepticus have epilepsyEpilepsy
Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...
. It is important to distinguish primary epileptic seizures from secondary causes. Blood tests, lumbar puncture
Lumbar puncture
A lumbar puncture is a diagnostic and at times therapeutic procedure that is performed in order to collect a sample of cerebrospinal fluid for biochemical, microbiological, and cytological analysis, or very rarely as a treatment to relieve increased intracranial pressure.-Indications:The...
or toxicology screening can be helpful in specific circumstances suggestive of an underlying cause like alcohol or benzodiazepine withdrawal, meningitis
Meningitis
Meningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs...
or drug overdose
Drug overdose
The term drug overdose describes the ingestion or application of a drug or other substance in quantities greater than are recommended or generally practiced...
, but there is insufficient evidence to support their routine use in the work-up of an adult with an apparently unprovoked first seizure. A 2007 review recommends an electroencephalogram and brain imaging with CT scan or MRI scan in the work-up. MRI is more sensitive in a first apparently unprovoked seizure.
Physical examination
Most patients are in a postictal statePostictal state
The postictal state is the altered state of consciousness that a person enters after experiencing a seizure. It usually lasts between 5 and 30 minutes, but sometimes longer in the case of larger or more severe seizures and is characterized by drowsiness, confusion, nausea, hypertension, headache or...
following a seizure. In this state they are drowsy and often confused. There may be signs of other injuries. A small study found that finding a bite to the side of the tongue was very helpful when present: while only a quarter of those with seizures had such a bite (sensitivity of 24%), the finding was very specific for seizures, with only 1% due to other causes (specificity of 99%).
Serum prolactin level
Two meta-analysesMeta-analysis
In statistics, a meta-analysis combines the results of several studies that address a set of related research hypotheses. In its simplest form, this is normally by identification of a common measure of effect size, for which a weighted average might be the output of a meta-analyses. Here the...
have quantified the role of an elevated serum prolactin
Prolactin
Prolactin also known as luteotropic hormone is a protein that in humans is encoded by the PRL gene.Prolactin is a peptide hormone discovered by Henry Friesen...
.
The first meta-analysis found that:
"If a serum prolactin concentration is greater than three times the baseline when taken within one hour of syncope, then in the absence of test "modifiers":
- the patient is nine times more likely to have suffered a GTCS as compared with a pseudoseizure positive LR = 8.92 (95% CI (1.31 to 60.91)), SN = 0.62 (95% CI (0.40 to 0.83)), SP = 0.89 (95% CI (0.60 to 0.98))
- five times more likely to have suffered a GTCS as compared with non-convulsive syncope positive LR 4.60 (95% CI (1.25 to 16.90)), SN = 0.71 (95% CI (0.49 to 0.87)), SP = 0.85 (95% CI (0.55 to 0.98)). "
The second meta-analysis found:
- "Elevated serum prolactin assay, when measured in the appropriate clinical setting at 10 to 20 minutes after a suspected event, is a useful adjunct for the differentiation of generalized tonic-clonic or complex partial seizure from psychogenic nonepileptic seizure among adults and older children (Level B)."
- "Serum prolactin assay does not distinguish epileptic seizures from syncope (Level B).
- "The use of serum PRL assay has not been established in the evaluation of status" epilepticus, repetitive seizures, and neonatal seizures (Level U)."
The serum prolactin level is less sensitive for detecting partial seizures.
EEG
An isolated abnormal electrical activity recorded by an electroencephalographyElectroencephalography
Electroencephalography is the recording of electrical activity along the scalp. EEG measures voltage fluctuations resulting from ionic current flows within the neurons of the brain...
examination without a clinical presentation is called subclinical seizure
Subclinical seizure
A Subclinical seizure is a type of seizure often experienced by people with epilepsy, in which an EEG trace will show abnormal brain activity, usually for a short duration of time but which does not present any noticeable clinical signs or symptoms...
. They can identify background epileptogenic activity, as well as help identify causes of seizures.
Determining the underlying cause
Additional diagnostic methods include CT Scanning and MRI imaging or angiography. These may show structural lesions within the brain and heart, but the majority of those with epilepsy show nothing unusual.As seizures have a broad differential diagnosis
Differential diagnosis
A differential diagnosis is a systematic diagnostic method used to identify the presence of an entity where multiple alternatives are possible , and may also refer to any of the included candidate alternatives A differential diagnosis (sometimes abbreviated DDx, ddx, DD, D/Dx, or ΔΔ) is a...
, it is common for patients to be simultaneously investigated for cardiac and endocrine causes. Checking glucose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
levels, for example, is a mandatory action in the management of seizures as hypoglycemia
Hypoglycemia
Hypoglycemia or hypoglycæmia is the medical term for a state produced by a lower than normal level of blood glucose. The term literally means "under-sweet blood"...
may cause seizures, and failure to administer glucose would be harmful to the patient. Other causes typically considered are syncope and cardiac arrhythmias, and occasionally panic attack
Panic attack
Panic attacks are periods of intense fear or apprehension that are of sudden onset and of relatively brief duration. Panic attacks usually begin abruptly, reach a peak within 10 minutes, and subside over the next several hours...
s and cataplexy
Cataplexy
Cataplexy is a sudden and transient episode of loss of muscle tone, often triggered by emotions. It is a rare disease , but affects roughly 70% of people who have narcolepsy...
. In addition, 5% of patients with a positive tilt table test
Tilt table test
A tilt table test, occasionally called upright tilt testing, is a medical procedure often used to diagnose dysautonomia or syncope. Patients with symptoms of dizziness or lightheadedness, with or without a loss of consciousness , suspected to be associated with a drop in blood pressure or...
may have seizure-like activity that seems to be due to cerebral hypoxia
Cerebral hypoxia
Cerebral hypoxia refers to a reduced supply of oxygen to the brain. Cerebral anoxia refers to a complete lack of oxygen to the brain. There are four separate categories of cerebral hypoxia; in order of severity they are; diffuse cerebral hypoxia , focal cerebral ischemia, cerebral infarction, and...
. For more information, see non-epileptic seizures
Non-epileptic seizures
Non-epileptic seizures are paroxysmal events that mimic an epileptic seizure but do not involve abnormal, rhythmic discharges of cortical neurons. They are caused by either physiological or psychological conditions...
.
Differential
Differentiating an epileptic seizure from other conditions such as syncope can be difficult. Other possible conditions that can mimic a seizure include: decerebrate posturing, psychogenic seizures, dystoniaDystonia
Dystonia is a neurological movement disorder, in which sustained muscle contractions cause twisting and repetitive movements or abnormal postures. The disorder may be hereditary or caused by other factors such as birth-related or other physical trauma, infection, poisoning or reaction to...
, migraine headaches, and strychnine poisoning.
Management
Potentially sharp or dangerous objects should also be moved from the vicinity, so that the individual is not hurt. After the seizure if the person is not fully conscious and alert, they should be placed in the recovery positionRecovery position
The recovery position refers to one of a series of variations on a lateral recumbent or three-quarters prone position of the body, in to which an unconscious but breathing casualty can be placed as part of first aid treatment.An unconscious person The recovery position refers to one of a series of...
.
A seizure longer than five minutes is a medical emergency. Caregivers may carry medicine.
Medication
The treatment of choice for someone who is actively seizing is lorazepamLorazepam
Lorazepam is a high-potency short-to-intermediate-acting 3-hydroxy benzodiazepine drug that has all five intrinsic benzodiazepine effects: anxiolytic, amnesic, sedative/hypnotic, anticonvulsant, antiemetic and muscle relaxant...
. This may be repeated if there is no effect after 10 minutes. If there is no effect after two doses, barbiturate
Barbiturate
Barbiturates are drugs that act as central nervous system depressants, and can therefore produce a wide spectrum of effects, from mild sedation to total anesthesia. They are also effective as anxiolytics, as hypnotics, and as anticonvulsants...
s or propofol
Propofol
Propofol is a short-acting, intravenously administered hypnotic agent. Its uses include the induction and maintenance of general anesthesia, sedation for mechanically ventilated adults, and procedural sedation. Propofol is also commonly used in veterinary medicine...
may be used. Ongoing medication is not typically needed after a first seizure and is generally only recommended after a second has occurred or those with structural lesions in the brain.
Other
A seizure response dogSeizure response dog
Seizure response dogs are a special type of service dog, specifically trained to help someone who has epilepsy or a seizure disorder.Due to the differing needs between each case, every potential seizure dog receives specialized training...
can be trained to summon help or ensure personal safety when a seizure occurs. These are not suitable for everybody. Rarely, a dog may develop the ability to sense a seizure before it occurs. Helmets may be used to provide protection of the head during a seizure.
Prognosis
In adults, after 6 months seizure free, after a first seizure the risk of a subsequent seizure in the next year is less than 20% regardless of treatment. Up to 7% of seizure that present to the emergency are in status epilepticusStatus epilepticus
Status epilepticus is a life-threatening condition in which the brain is in a state of persistent seizure. Definitions vary, but traditionally it is defined as one continuous unremitting seizure lasting longer than 5 minutes, or recurrent seizures without regaining consciousness between seizures...
. In those with a status epilepticus mortality is between 10 and 40%.
Epidemiology
About 7 per 1000 people in the United States have a seizure in a given year. Rates are highest in those less than 1 year of age and greater than 55.History
Seizures were long viewed as an otherworldly condition being referred to by HippocratesHippocrates
Hippocrates of Cos or Hippokrates of Kos was an ancient Greek physician of the Age of Pericles , and is considered one of the most outstanding figures in the history of medicine...
in 400B.C. as "the sacred disease".