World Epilepsy Day: An article on the diagnosis and differential diagnosis of epilepsy

With the improvement of people's living standards, the spectrum of human diseases has also changed, resulting in an increase in the incidence of epilepsy year by year, which seriously affects people's life and health
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Since 2015, the International Epilepsy Association (IBE) and the International League Against Epilepsy (ILAE) have jointly proposed that the second Monday of February each year be designated as "International Epilepsy Day", or "World Epilepsy Day"
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Today is World Epilepsy Day, let's learn about the diagnosis and differential diagnosis of epilepsy together
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Epilepsy diagnosis Epilepsy is a disease caused by a variety of etiologies, and its diagnosis should follow a three-step principle: first, determine whether the epileptic symptoms are epileptic seizures; second, determine the type of epilepsy and whether it is an epilepsy syndrome; finally, determine what the cause of the seizure is
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Clinical features Different types of epilepsy have different clinical seizure features, but all seizures have common features: 1.
Paroxysmal, seizures occur suddenly, recover quickly, with normal intervals; 2.
Transient, each seizure lasts for several seconds, Scores or counts for 10 minutes; 3.
Repetitive, with multiple seizures from time to time; 4.
Stereotype, each type or patient has almost the same performance for each seizure
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Auxiliary examination ➤ EEG: EEG is the most important auxiliary examination method for the diagnosis of epilepsy, which can confirm the diagnosis, classification and specific syndrome of epilepsy
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Conventional EEG can detect epileptiform discharges in about 50% of patients, and induction techniques such as hyperventilation, flash stimulation, sleep or sleep deprivation can improve the detection rate
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24-hour long-term EEG monitoring and video EEG can increase the likelihood of epileptiform discharges and help to identify seizure-like disorders such as syncope, transient ischemic attack, cataplexy, and hysteria
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However, some patients with epilepsy are always normal in EEG examination, while a few normal people occasionally detect epileptiform discharges, so it is not possible to determine whether epilepsy is epilepsy based solely on the changes of EEG
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➤Neuroimaging examination: CT and MRI should be used as routine examinations to exclude intracranial organic lesions, which can determine whether there is abnormal brain structure, and can be used for the etiological diagnosis of epilepsy, and MRI diagnosis is more sensitive
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Functional imaging examinations such as SPECT and PET can reflect local metabolic changes in the brain from different angles, which are helpful for the localization of epileptic lesions
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➤Others: For infectious diseases of the central nervous system, especially cerebral cysticercosis, routine, biochemical, immunological and molecular biological examinations of cerebrospinal fluid are meaningful for identifying the etiology of epilepsy
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Other tests such as blood sugar, blood calcium, blood magnesium, liver function and renal function are also important for the diagnosis of certain epilepsy
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Differential diagnosis ➤ syncope: transient loss of consciousness and falls caused by diffuse transient cerebral ischemia and hypoxia
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Some patients may have limb rigidity or clonus, which needs to be differentiated from absence seizures and generalized seizures
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Diagnosis of syncope is based on: 1.
There are many obvious incentives, such as anxiety, pain, blood, severe cold, emotional agitation, prolonged standing, coughing, suffocation, urination, defecation, etc.
; 2.
The attack is often accompanied by pale face, black eyes, and cold sweat 3.
The occurrence and recovery of falls are slow, and there is an obvious post-ictal state; 4.
Cardiogenic, brain-derived, neurogenic and hypoglycemic syncope, often accompanied by symptoms and signs of the corresponding primary disease; 5.
EEG detection mostly without epileptiform discharge
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➤ Pseudo-seizure: It is a non-epileptic seizure disorder, which is abnormal brain function caused by psychological disturbance rather than brain electrical disturbance
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The clinical manifestations are similar to epilepsy and difficult to distinguish
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The absence of epileptiform discharges on EEG during seizures and the ineffectiveness of antiepileptic drug treatment are the keys to distinguish it from epilepsy
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However, it should be noted that 10% of patients with pseudo-seizures may be accompanied by epilepsy, and 10% to 20% of patients with epilepsy have pseudo-seizures
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➤ Migraine: Identification points: 1.
Migraine is characterized by severe unilateral or bilateral headaches, while epilepsy headaches are milder and usually appear successively; 2.
Epilepsy EEG is paroxysmal spikes or spikes Epileptiform discharges such as slow complex waves, and migraine are mainly focal slow waves; 3.
Visual hallucinations can occur on both sides, but complex visual hallucinations are more common in epilepsy; 4.
The incidence of disturbance of consciousness in epileptic seizures is high
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➤Hypertensive encephalopathy: Different degrees of disturbance of consciousness, severe headache, nausea and vomiting, and convulsions are the three main whole-brain symptoms of hypertensive encephalopathy.
The gradual disappearance of symptoms with the decrease of blood pressure is an important basis for distinguishing from epileptic convulsions
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➤ Febrile seizures: Febrile seizures are closely related to epilepsy, and there is a high chance of seizures after complex febrile seizures.
Although they are all manifested as seizures, febrile seizures are not epilepsy
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Afebrile seizures are characteristic of epilepsy
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➤Hyperventilation syndrome: Hyperventilation syndrome is mainly caused by psychological factors, induced by inappropriate hyperventilation, and clinically manifested as various episodic somatic symptoms.
One of the major diseases recognized by the patient or physician
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The episodic psychiatric symptoms, transient loss of consciousness and limb twitches it causes should be differentiated from automatisms, absence seizures and generalized seizures of epilepsy, respectively
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The patient's symptoms can be reproduced by hyperventilation, which is the main basis for identification.
There is no epileptiform discharge on the EEG during or during the attack, and the blood gas analysis before and after the attack shows that the partial pressure of carbon dioxide is also an important identification point
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➤ Transient ischemic attack (TIA): Identification points: 1.
TIA is more common in the elderly, often with a history of arteriosclerosis, coronary heart disease, hypertension, diabetes, etc.
The duration varies from minutes to hours, while epilepsy It can be seen at any age, mostly in adolescents, the aforementioned risk factors are not prominent, the onset time is mostly a few minutes, rarely more than 5 minutes; 2.
The clinical symptoms of TIA are mostly absence rather than stimulation, so the loss or decrease of sensation is more than paresthesia.
3.
The twitching of the limbs in TIA patients is similar to epilepsy on the surface, but most patients have no family history of epilepsy, and the twitching of the limbs is irregular, and there is no head and neck rotation; Transient global amnesia is a memory disorder that occurs suddenly without warning.
It is more common in the elderly over 60 years old.
The symptoms often last for 15 minutes to several hours.
The probability of recurrence is less than 15%.
There is no obvious epilepsy on the EEG.
Epileptic discharges; epileptic amnesia episodes are shorter in duration, often have recurrent seizures, and are often characterized by epileptic discharges on EEG
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The diagnosis of epilepsy also needs to consider the results of EEG
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➤Others: Epilepsy manifested as convulsions should also be differentiated from hypocalcemic convulsions, non-epileptic seizures after head injury, and eclampsia; nocturnal seizures should be distinguished from narcolepsy disorders: including sleepwalking, night terrors, and periodic legs during sleep Disorders of movement and rapid eye movement sleep
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