Abscesses in adults and children: typical, atypical, simple and complex

It happens that a person loses consciousness for a certain moment for no reason - as a rule, this is more common in childhood, and is called "absence". Outwardly, it looks like a temporary frozen state with an "empty" look. Absence is considered a mild form of an epileptic seizure: such a condition cannot be ignored, as it is fraught with quite negative consequences.

[ 1 ], [ 2 ]

Epidemiology

Absence was first discussed in the 17th-18th centuries. The term literally translated from French means "absence", meaning a temporary loss of consciousness in the patient. Neurologists also use an additional term related to absences - "petit mal", which translates as "little illness".

Absence is a type of generalized epilepsy and is most often found in pediatric patients, mostly aged 4 to 7 years, sometimes aged 2 to 8 years. In many children, loss of consciousness occurs in combination with other types of epileptic manifestations.

Girls are more likely to get sick, but the disease can also occur in boys.

According to statistics, absence occurs in 20% of all diagnosed childhood epilepsies.

If absence is the dominant clinical symptom, the patient is diagnosed with absence epilepsy.

Adults get sick much less often – only in 5% of cases.

[ 3 ], [ 4 ], [ 5 ], [ 6 ], [ 7 ], [ 8 ], [ 9 ]

Causes absences

The basic cause of absence is considered to be a violation of the balance of inhibitory and excitatory processes in the nerve cells of the cerebral cortex. Depending on this, absence can be of two types:

• Secondary absence is caused by factors that change biological-electrical activity. These factors can be inflammatory processes (abscess, encephalitis), tumor processes. In such a situation, absence becomes a symptom of the underlying pathology.
• Idiopathic absence is a disease of uncertain etiology. Presumably, such pathology is hereditary, as indicated by family episodes of the disease. Idiopathic absence usually manifests itself in the period from 4 to 10 years.

Despite the fact that absences are considered to be genetically determined pathologies, the nuances of inheritance and the involvement of genes currently remain unknown.

[ 10 ], [ 11 ], [ 12 ], [ 13 ]

Risk factors

Spontaneous absence seizures may occur if one of the following risk factors is present:

• heredity, by type of chromosomal aberration;
• problems that arise during pregnancy and labor (oxygen starvation, prolonged intoxication, infections, trauma during childbirth);
• neurointoxications and infections;
• head injuries;
• severe exhaustion of the body;
• strong hormonal changes;
• metabolic disorders, degenerative processes affecting brain tissue;
• tumor processes in the brain.

In most cases, the recurrence of an attack is also associated with the impact of a certain factor. Such a factor may be a flash of light, frequent flickering of episodes, excessive nervous tension, a sharp forced influx of air, etc.

[ 14 ], [ 15 ], [ 16 ], [ 17 ], [ 18 ], [ 19 ], [ 20 ]

Pathogenesis

The mechanism by which absence develops has not yet been precisely determined. Scientists have conducted a fairly large number of different studies on this issue and have established that the cortex and thalamus, as well as inhibitory and excitatory transmitters, play a certain role in the development of the disease.

It is possible that the pathogenetic basis is genetically determined abnormal abilities of nerve cells. Experts believe that absence develops with the dominance of blocking activity. This is the main difference between absence and convulsive paroxysm, which is the result of overexcitation.

Hyperinhibitory activation of the cortex can arise as a compensatory mechanism to suppress the painful excitation that has occurred.

The development of absence in a child and the overwhelming disappearance of the problem as he or she grows older indicates a relationship between the pathology and the degree of maturity of the brain.

[ 21 ], [ 22 ], [ 23 ], [ 24 ], [ 25 ], [ 26 ], [ 27 ], [ 28 ]

Symptoms absences

Absence usually develops without any precursors, against the background of an absolutely favorable state. The attack is spontaneous, it cannot be predicted or calculated in advance.

Only in isolated cases do patients notice the first signs of an approaching paroxysm. This includes a sudden headache and nausea, increased sweating and rapid heartbeat. In some cases, relatives notice that immediately before the attack the child may behave inexplicably - for example, unmotivated irritability or capriciousness occurs. In isolated cases, auditory, sound or taste hallucinations appear.

But, as we have already noted, the first signs are not observed in all patients. Usually, common symptoms are found in all cases:

• The attack develops abruptly and ends in the same way. The patient seems to "freeze"; outwardly, this may resemble "thoughtfulness", without any reaction to a call or other irritants. The duration of the paroxysm is on average 12-14 seconds, after which the patient comes to his senses, as if nothing had happened. Neither weakness nor drowsiness occurs after the attack.
• If the patient suffers from a complex course of absence, then the "switching off" may be accompanied by a tonic component. It may look like this: the patient stops abruptly, if there was something in his hands - it falls out, the head falls back. The person rolls his eyes, sometimes makes repeated sounds or smacks his lips (the so-called automatisms).

Absence attacks are repeated with varying frequency – from 6-9 per day to several hundred times – mainly in a state of wakefulness (during the daytime).

Absence at night is considered rare, but its occurrence is possible during the slow sleep phase. It is almost impossible to notice the paroxysm from the outside. However, if special sensors are attached to the patient that read nerve impulses, then the corresponding pathological signs can be detected.

[ 29 ], [ 30 ], [ 31 ], [ 32 ]

Absences in adults

Absences develop much less frequently in adults than in children – only in 5% of cases. Doctors associate the occurrence of this problem with the lack of necessary therapy at an earlier age – for example, when the patient was a teenager.

The duration of a paroxysm in adult patients is a few seconds, so the attack may not be noticed from the outside. In medicine, this is called "minor absences" when the attack lasts only a couple of seconds and is repeated infrequently. However, the difficulty is that loss of consciousness can occur while driving a car, or when working with dangerous devices and mechanisms. A person can "switch off" while swimming in a pool, or in another potentially dangerous situation.

In adults, the disease may be accompanied by tremors of the upper body and head, which often leads to impaired motor coordination. However, most often the seizure does not have any specific symptoms: there are no convulsions or myoclonus of the eyelids, the patient simply "switches off" for a certain time, suspends his activity, "freezes".

If you ask the patient what happened during these few seconds of the seizure, the person will not be able to answer anything, since his consciousness was switched off during this period.

[ 33 ], [ 34 ]

Absences in children

In childhood, absence epilepsy is more often detected, which is related to the varieties of idiopathic epilepsy. This form is predominantly hereditary (in about 2/3 of patients).

Childhood absences occur mostly in girls aged two to eight years. The prognosis for such a disease is usually favorable and benign: the disease lasts about six years and ends either in complete recovery or in long-term stable remission (up to twenty years). The main condition for a positive outcome is timely detection and treatment.

It should be noted that parents do not always pay attention to the presence of attacks - often they simply go unnoticed. Absences in infants are especially unnoticeable - such attacks last no more than a couple of seconds, and are not accompanied by any special symptoms.

Depending on the age category when absence is first detected, the disease is divided into childhood (under seven years) and juvenile (adolescence).

The International Commission ILAE identified four childhood syndromes in which absences are observed at different stages:

• childhood absence epilepsy;
• juvenile absence epilepsy;
• juvenile myoclonic epilepsy;
• myoclonic absence epilepsy.

More recently, it has been proposed to include other syndromes accompanied by typical absence in the classification list:

• myoclonus of the eyelids with absences;
• perioral absence epilepsy;
• stimulus-sensitive absence epilepsy.

Atypical paroxysms may be observed in patients with Lennox-Gastaut syndrome, a syndrome of continuous spike-wave activity during slow-wave sleep.

[ 35 ]

Forms

Absences have a number of varieties, depending on the course, stage, form of the underlying disease, the symptoms present, etc. First of all, the disease is divided into two basic types:

• typical absences (they are also called simple);
• atypical absences (so-called complex).

Simple absences are short-term, abruptly arising and ending attacks that occur without any significant change in muscle tone.

Complex absences most often appear in childhood, against the background of impaired mental development, and are accompanied by symptomatic epilepsy. During the paroxysm, there is a fairly strong hyper- or hypotonia of the muscles, which is also indicated in the classification of the disease. Some specialists use the term "generalized absences" when describing complex paroxysms, which indicates that the disease is accompanied by generalized myoclonus.

According to the degree of change in muscle tone, the following are distinguished:

• atonic absences;
• akinetic absences;
• myoclonic absences.

The listed conditions are complex absences: they are easily identified by motor characteristics associated with changes in muscle tone. Atonic paroxysm manifests itself as decreased muscle tone: this is noticeable by the drooping of the arms and head. If the patient was sitting on a chair, he can literally "slide" off it. In akinetic paroxysm, a standing patient falls abruptly. Flexion or extension movements in the limbs, throwing back the head, bending the body can be observed. In myoclonic absence, typical muscle contractions with a small motor amplitude are present - the so-called twitching. Muscle contractions of the chin, eyelids, lips are often noted. Twitching occurs symmetrically or asymmetrically.

Complications and consequences

In most patients, typical manifestations of absence disappear by about 18-20 years of age. And only in some cases does the disease degenerate into a grand mal seizure - in such patients the problem lasts a long time or remains for life.

The transition to the status state occurs in 30% of cases. The status lasts from about 2 to 8 hours, less often - for several days. Signs of such a complication are confusion of consciousness, varying degrees of disorientation, inadequate behavior (with preserved movements and coordination). Speech activity is also impaired: the patient pronounces mainly simple words and phrases, such as "yes", "no", "I don't know".

Experts point out several signs that indicate a positive tendency for absence:

• early onset of the disease (between four and eight years of age) with a normal level of intelligence development;
• absence of other paroxysmal conditions;
• positive changes during monotherapy using one anticonvulsant drug;
• unchanged EEG pattern (typical generalized spike-wave complexes do not count).

Atypical absences respond poorly to treatment, so the consequences of such diseases depend on the course of the underlying pathology.

During the period of attacks, difficulties with socialization may be observed: the occurrence of attacks and the degree of their manifestation are difficult to predict. The probability of injury during a paroxysm is not excluded. Thus, patients often experience falls, head injuries, fractures.

[ 36 ], [ 37 ], [ 38 ], [ 39 ], [ 40 ]

Diagnostics absences

The main diagnostic procedure that allows confirmation of absence is the assessment of brain electrical activity, or electroencephalography. EEG is a very sensitive research method that indicates minimal functional changes in the cerebral cortex and deep structures. EEG has no alternative: even the well-known diagnostic procedures PET (two-photon emission tomography) and fMRI ( functional magnetic resonance imaging ) cannot compare with this method in terms of information content.

Other methods are used only if, for some reason, it is impossible to conduct an EEG:

• magnetic resonance imaging;
• computed tomography;
• positron emission tomography;
• single photon emission tomography.

The listed diagnostic procedures help to register structural changes in the brain – for example, traumatic injuries, hematomas, tumor processes. However, these studies do not provide information about the activity of brain structures.

Electroencephalography is able to demonstrate a distinctive feature of a typical absence seizure: impaired consciousness correlates with generalized spike and polyspike-wave activity (discharge frequency 3-4, less often 2.5-3 Hz).

In atypical absence, the EEG shows slow wave excitations - less than 2.5 Hz. The discharges are characterized by heterogeneity, jumps and asymmetry of peaks.

[ 41 ], [ 42 ]

Differential diagnosis

Absence is distinguished from other types of epilepsy, where a short-term loss of consciousness is only one of the leading symptoms. For example, typical absences are distinguished from complex focal seizures.

	Focal epilepsy seizures	Typical absence
Preceding aura	Everywhere.	Absent.
Duration	Mostly more than a minute.	5-20 seconds.
The effects of hyperventilation	In isolated cases.	Everywhere.
Photosensitivity	In isolated cases.	In many cases.
Loss of consciousness	Usually deep.	Variations are possible depending on the current.
The emergence of automatisms	Almost always involving one side of the trunk and limb.	Mild, without involvement of the trunk and limbs.
The emergence of outpatient automatisms	Everywhere.	Only in the absence status.
The appearance of clonic seizures	In rare cases, unilateral, as the end of an attack.	Often, bilaterally, near the oral cavity and eyelids.
No cramps	In isolated cases.	It is quite possible.
Post-ictal symptoms	In almost all cases: confusion, amnesia, dysphasia.	Absent.

Paroxysms of focal epilepsy are characterized by combined motor automatisms, hallucinatory states, and rich post-ictal clinical symptoms.

Absence or thoughtfulness?

Many parents at first cannot tell the difference: is the child really having an absence, or is the baby just thinking for a few seconds? How can you tell if the seizure is real?

In such a situation, doctors advise knocking loudly or clapping your hands. If the child turns around at the sound, it means that we are talking about a false absence or banal "thoughtfulness". This question can only be answered accurately after conducting a diagnostic EEG.

Treatment absences

Treatment for absences is quite complicated, primarily because the body periodically develops resistance. Therefore, the approach to therapy should be individual and differentiated: anticonvulsants are prescribed in accordance with the type and etiology of attacks.

• In typical absences, monotherapy is acceptable, using Ethosuximide, valproic acid. The proposed medications demonstrate an effect in more than 70% of patients. In the development of resistance, monotherapy is combined with Lamotrigine, in small doses.
• In idiopathic cases of absence, monotherapy with anticonvulsants is used, which are active against all types of seizures. As a rule, Levetiracetam or valproic acid derivatives are used - such medications are equally effective both for absences and for myoclonic or tonic-clonic paroxysms. If there is a combination of absence and tonic-clonic seizures, then it is appropriate to prescribe Lamotrigine.
• In atypical absence, monotherapy is carried out using valproic acid, Lamotrigine, Phenytoin. Sometimes it is necessary to connect steroid drugs. It is undesirable to use Tiagabine, Carbamazepine, Phenobarbital, due to the likelihood of increased symptoms.
• If monotherapy is ineffective, a number of drugs are prescribed. As a rule, anticonvulsant medications are combined with each other, taking into account the individual characteristics of the patient and the disease.

The dosage of the selected anticonvulsant is gradually reduced, up to its discontinuation, but only in the case of stable remission for 2-3 years. If repeated episodes of epilepsy are detected, then the underlying pathology is treated, against the background of symptomatic therapy.

If the cognitive side is affected, then a psychologist is definitely involved in the treatment.

Help with absences

Absence is a short-term depression of consciousness, and it develops unpredictably. It is believed that in most cases such moments pass almost unnoticed by others, because the attack lasts no more than a few seconds.

Absence appears as a short pause in motor and speech activity. Mostly, the patient does not need any specific help. The only thing that should be focused on is ensuring the patient's safety. In no case should the person be left alone until consciousness is fully restored.

Is it possible to distract a child from absence seizures?

There is such a thing as a false absence - this is a "freezing", "looping" on one point, which disappears if the patient is called, touched, or simply clapped sharply. A real absence cannot be stopped by such measures, so it is believed that it will not be possible to distract a person from a real attack.

It is also impossible to prevent an attack, since it usually begins suddenly and unpredictably.

Since the absence does not last long, you should not try to influence the patient in any way - the attack will end on its own, just as it began.

Prevention

Full prevention of absence consists of eliminating any moments that can provoke an attack. Thus, it is necessary to prevent the development of stress, psycho-emotional situations, fears in advance. The emergence of conflicts and disputes should be reduced to a minimum.

It is also no less important to spend less time watching TV or computer. Instead, you should rest more (active rest is welcome), get a good night's sleep.

In addition, it is necessary to take care of your health and prevent injuries and inflammatory processes.

There is no specific prevention for absences.

[ 43 ], [ 44 ]

Forecast

Absences are considered benign pathologies, since 80% of patients experience stable remission over time - of course, if the patient received timely medical care and completed a full course of treatment.

In some cases, single attacks recur in old age. This condition requires additional anti-relapse treatment, while observing personal safety rules. Until the attacks are completely stopped, such people do not have the right to drive a car or work with any mechanisms.

As for the general development of children suffering from absences, it does not differ from that of their other peers. Of course, in some cases there is a lack of physical or intellectual development, but these are only isolated cases, and only under the condition of a malignant course of the disease.

And yet, we must not forget that frequent repeated attacks can lead to certain problems with the child's concentration. The suffering child can become withdrawn, inattentive, and this will sooner or later affect the quality of his studies. Therefore, children diagnosed with "absence" should be under the supervision of not only a doctor, but also teachers and educators.

[ 45 ], [ 46 ]