Seizure

	Main Article	Discussion	Related Articles  [?]	Bibliography  [?]	External Links  [?]	Citable Version  [?]
	This editable Main Article is under development and subject to a disclaimer. [edit intro]

In humans, seizures are "Clinical or subclinical disturbances of cortical function due to a sudden, abnormal, excessive, and disorganized discharge of brain cells. Clinical manifestations include abnormal motor, sensory and psychic phenomena. Recurrent seizures are usually referred to as epilepsy or "seizure disorder.""^[1]

Status epilepticus is a "prolonged seizure or seizures repeated frequently enough to prevent recovery between episodes occurring over a period of 20-30 minutes."^[2]

Diagnosis[edit]

Determining whether a seizure occurred[edit]

Differentiating a seizure from other conditions such as syncope can be difficult. In addition, 5% of patients with a positive tilt table test may have seizure like activity that seems to be due to cerebral hypoxia.^[3]

Medical history taking[edit]

Video-documented signs during video electroencephalography can help distinguish epileptic seizures and pseuodseizures; however, eye-witness reports of the presence of these signs are unreliable:^[4]

• predictive of psychogenic nonepileptic seizures: "preserved awareness," "eye flutter," and "bystanders can intensify or alleviate"
• predictive of epileptic seizures: "abrupt onset," "eye-opening/widening," and postictal "confusion/sleep"

Interviewing witnesses must be carefully done.^[5] Allowing observers to answer "I do not know" may be important.^[5]

Physical examination[edit]

A small study found that finding a bite to the side of the tongue was very helpful when present^[6]"

• sensitivity of 24%
• specificity of 99%

A more recent meta-analysis yielded similar results.^[7]

Serum prolactin level[edit]

Two meta-analyses have quantified the role of an elevated serum prolactin. The first meta-analysis found that^[8]: "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":

1. 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))
2. 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:^[9]

1. "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)."
2. "Serum prolactin assay does not distinguish epileptic seizures from syncope (Level B).
3. "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.^[10]

EEG[edit]

An isolated abnormal electrical activity recorded by an electroencephalography examination without a clinical presentation is called subclinical seizure. They may identify background epileptogenic activity, as well as help identify particular causes of seizures.

About 25% of adults with a first, unprovoked seizure will have an abnormal EEG.^[11] These patients are at higher risk of recurrence.^[11]

Brain imaging[edit]

About 10% of adults with a first, unprovoked seizure will have an abnormal brain imaging study (CT or MRI).^[11]

Complications[edit]

Status epilepticus[edit]

Status epilepticus is a "prolonged seizure or seizures repeated frequently enough to prevent recovery between episodes occurring over a period of 20-30 minutes."^[2]

References[edit]

See also[edit]

• Epilepsy