Epileptic Seizion, Clinical Manifestations

Epileptic seizion, clinical manifestations

The epileptic seizure has different clinical manifestations, which allows to divide it into three phases: 

1. Pre-ictal where it precedes the convulsive episode, has a variable duration, from a few seconds to several days and is characterized by behavioral changes such as anxiety, fear, abnormal perception, excitability, impulsivity, defensive and aggressiveness and even vegetative manifestations such as, sialorrheaVomiting and mydriasis, 
2. Lictus in itself, lasts from several seconds a few minutes generally less than two minutes its manifestations are variable since it depends on the area of the affected brain, however, it can include motor, autonomic, behavior and conscience changes 
3.  Post-ictal, it is the neuronal recovery period after the convulsive episode and that also has a variable duration, from a few more frequent minutes to rare days, precipitating a cognitive impairment, the animal can show disorientation, compulsive march, low performanceIn space work memory activities, deafness, ataxia, depression, aggression and vocalizations.

Therefore, convulsive crises can be influenced to trigger factors among them we have visits at home, a change in the situation of life, change in daily routine, altered sleep patterns, unknown places, climate and hormonal factors, focusing on These hormonal factors, in a study, whose purpose was to deter if there was a relationship between the stral cycle of dog females and the appearance of seizures in entire dogs with alleged idiopathic epilepsy, suggested that progesterone has protective effects against seizures, put That in the different stages of the stral cycle, there are some intervals where there is a partial decrease in this way its protective effects in the nervous system and thus influencing the appearance of these epileptiform crises, following the largest number of factors with the context Single dog precipitators is 9, the stress being the trigger factor and more frequent having pro -convulsive effects affecting the brain excitely.

In order to group patients, standardize diagnoses and facilitate the comparison of different cases, it is necessary to understand the convulsive crises by classifying them in order to improve the evaluation of therapeutic options; From an etiological point of view, this neurological disease is characterized by recurring convulsions of unknown origin despite the fact that it is apparently independent of the race, some dog breeds, show a greater predisposition, which leads to consider that this condition can have genetic influence , dogs of the Border Collie race with idiopathic epilepsy have a variation of a single c-g-180t It seems to play a role in the component of idiopathic epilepsy as a low -penetrated risk gene in 37 races of which they have presented idiopathic epilepsy, being able to play an important role in the pathophysiological mechanism of this disease, so It requires that in these their function and expression in neurons be evaluated in order to improve the understanding of L To molecular pathogenesis, it should be noted that there are other alterations that cause convulsive crises such as intracranial structural lesions, unlike idiopathic epilepsy, in this form of epilepsy, in addition to seizures, animals show other neurological changes, also other extracranial alterations generally to causes to causes of metabolic origin such as hypocalcemia, hypoglycemia, thiamine deficiency, among others, these may not be considered as a form of epilepsy, since seizures cease after the main cause is resolved.

 The clinical or semiological form, in which epileptic crises are manifested indicate the origin of the epileptogenic focus since these can be focal or generalized, the focus originate in only one of the hemispheres with a normal or altered state of consciousness, subdividing themselves in Motor or autonomous and generalized affects both cerebral hemispheres, with loss of consciousness, followed by symmetric tonic-clonic contractions of the muscles of the extremities, neck and face; The most common way is isolated epileptic crises, in which the animal has two or more episode of crisis in a 24 -hour period, last less than two minutes and between each one the animal recovers consciousness this condition is known as seizures of Cluster or cluster, instead in which two or more seizures occur within 24 hours, with a duration of more than five minutes and the animal does not recover consciousness between each episode is known as epileptic status, a patient with this Condition needs urgent medical attention.

In how much and holding the fact that idiopathic epilepsy is an unknown etiological condition and before this it requires a diagnosis that is abstained by discard, the difficulty that arises to reach a definitive diagnosis is notable, therefore, the orientation must be carried outthoroughly following a protocol that includes from an anamnesis which should be as complete as possible in all phases of convulsive crises, a physical examination to detect the possible concomitant or not related conditions to seizures and an integral neurological examination since during thisExam can be observed some neurological deficits thus contemplating during the post-ictal phase, however, it is considered that animals under the effect of anticonvulsive medication can also show cognitive impairment such as canines treated with polytherapy based on zonosamide and bromide ofPotassium exhibit less training capacity. Finally, the protocol must address the use of complementary laboratory and image tests.

The first thing that is carried out in laboratory tests includes complete blood count (hemogram), serum biochemistry (glucose, electrolytes such as sodium, potassium and chlorine, total and differentiated proteins, aspartate aminotransferase (AST), Alanino Aminotransferase (ALT), Alkaline phosphatase (fas), calcium and cholesterol) and urine analysis (urea and creatinine), with this some metabolic origin disorders are discard , selenium and zinc can suggest a role in the pathophysiology or treatment of canine idiopathic epilepsy, while the analysis of cerebrospinal fluid in cases of suspicion of idiopathic epilepsy is commonly used to discard the diagnosis of convulsive disorders of inflammatory and infectious ethology, by Its use as a direct diagnosis in patients with idiopathic epilepsy would have a low value, however, even To a better compression, the determination of the laboratory of markers such as GABA and glutamate in the cerebrospinal fluid is possible, allowing to identify that animals are more likely to have new episodes and which therapeutic therapy is the most appropriate, this must be performed after magnetic resonance, Not to alter the images obtained.

After laboratory exams, image tests are performed, to rule out possible tumor masses that may cause seizures, magnetic resonance is the technique of choice to diagnose intracranial changes, the contrast administration is only indicated when injuries are detected, to Despite this, it is currently used in most patients, although it is considered that an animal with idiopathic epilepsy has no abnormalities in magnetic resonance, postcerebral lesions can be detected, which generally lies in a seemingly higher diffusion coefficient with areas of areas of T2 hyperintensity mainly at the level of the piriform and temporal lobe bark within the cingualad and hippocampus circumference, patients with idiopathic epilepsy have hypochocampus asymmetry, in which they demonstrate a volume change of 0.53cm, these changes are a consequence of epileptic crises recent and not the cause of crises, to Lugo changes can cause uncertainty at the time of diagnosis, so it is recommended to repeat magnetic resonance around the sixteen week in which the patient ceases. 

The electroencephalogram is the graphical representation of the electrical activity of the brain, allowing the recognition of epileptic activity, identification of focal brain lesions and evaluation of evolution to the therapeutic response of epileptic crises, although a protocol has not yet been established in veterinarianTo standardize its use and is currently not used as a routine test, when used, it allows to demonstrate the presence of epileptiform discharges detectable in the exam and a decrease in unilateral volume of the hippocampus with magnetic resonance, both tests provide a diagnostic valuemore effective when they are done together .

The epileptic attack is thus produced by a neuronal paroxysmal discharge, which is recurrent and generally self-limited, without a way of predicting when and how serious it will occur, although there is no definitive treatment for idiopathic epilepsy, these attacks can be controlled with medications indefinitely, So, this must be symptomatic and preventive, whose purpose will be to reach the longest interval without convulsions and that in the event that they occur, they are the least serious possible, in relation to idiopathic epilepsy, monotherapy must always be chosen As the initial therapy, that is, the administration of a single drug, since in this way it will be better unequivocally, the effectiveness and safety of the selected medication, being necessary to inform the owner of the complexity of the treatment, by virtue of the possibility of adverse effects or refractory animals where it would be constantly needed to adjust the doses, change or Add medications, being an exhausting and frustrating process for the owner as for the veterinarian.

An animal with an acute epileptic crisis is considered a medical emergency especially when it is in epileptic status, it is usually due to the release of catecholamines in each crisis, which stimulate the sympathetic nervous system causing the increase in heart rate, pressurearterial and muscular activity, subsequent trigger reactions that could cause death to the animal.  Midazolam is a sedative anxiolytic action toLong -term treatments, since it would require a greater frequency of administration, in urgent situations the route of administration of Midazolam is elementary since it is sought that the central nervous system be used immediately being used by the intravenous route, however, the intranasal administrationIt is a viable option since by establishing intravenous access in a dog with convulsive crisis, it is problematic, delaying the control of the patient, therefore this route offers alternatives as to its fast and non -invasive administration of easily accessible for both the veterinarian and forThe owner with a reduction in seizures is around 33 to 64 sec.

Consistent of what has already been mentioned above, that it is a disease that has no cure, requires a continuous medication, restricting neuronal hyperexcitation situations, reducing the seriousness of the crises, taking into account the quality of the patient andThe security of the medication used to choose the medication that will be administered is necessary to know its mechanism of action, pharmacodynamics and pharmacokinetics, in order to know its secondary therapeutic effects, such as its duration of action and power, it is advisable to always begin treatment with the more dose treatmentLow, in order to observe the effect and tolerance for an established period, adjusting the doses, until finding the appropriate and effective.

The phenobarbital is a drug that can be used to treat acute and chronic attacks of epilepsy, it is a potential of the inhibitory action of the GABA, thus increasing the membrane excitability threshold, reducing the probability of seizures, as it presents activity in activity inCalcium channels and conductibility of sodium and potassium ions. When used as a long -term treatment, it is commonSide effects, dependence and medicine tolerance, between the adverse effects we commonly find sedation, polyphia, polydipsia and polyuria, therefore to control the accumulation of phenobarbital and the possible side effects, it is suggestedto reach stable blood levels of 20-45 UG/ml.

Imepitine is a state -of -the -art drug, whose mechanism of action is to improve the regulatory activity of the GABA, which leads to the hyperporation of the membrane, causing an increase in the excitability threshold by reducing the probability of seizures and generating an action of Blocking in calcium channels, thus presenting a series of advantages since being an agonist of low affinity for benzodiazepines of chlorine channels, does not cause dependence, since it has an action dependent on the GABA and dose -dependent, dose -dependent, Reducing the risk of overdose, being a short half -life medicine reduces its accumulation and with this the appearance of side effects, so its use in veterinary medicine has recently been approved, suggesting an effective minine dose of 19mg/kg/each 12 hours, a minority of patients can present side effects such as polyphia and does not seem to improve behavior related to anxiety in Dogs with idiopathic epilepsy, not all patients react correctly to the medication, so that cases of refractory can be presented, for this different combinations of drug are analyzed that may be useful at the time of which the patient does not tolerate imepitoine as monotherapy, Several studies have suggested that the combination of imepitoin and phenobarbital at low initial dose of 5mg/kg/every 12 hours, significantly reduces the frequency of crises around 50% of patients, as well as the use of phenobarbital or bromide of Potassium in patients who are refractory at maximum doses of 30mg/kg/every 12 hours of imepitoine, since the frequency of monthly seizures decreases, being able to be used as an optional treatment. 

The slighttam is a drug that has no license for veterinary use, however, the American School of Internal Veterinary Medicine (ACVIM) recommends its use as an adjuvant, so it deserves to be addressed, it is a third generation medication of the Pirrolidones group, acts on calcium channels of type N inhibiting it by improving inhibitory activity, with high safety profile, mild side effects and its long -term administration does not seem to generate tolerance or dependence, a study suggests that, it is not effective as monotherapy in dogswith idiopathic epilepsy so it has the possibility of losing its medium term effect.

Finally, the increase in number of cases to patients refractory to pharmacology therapy, has focused on new research on non -pharmacological options, one of these is the use of diets, where in sick animals this becomes increasingly relevant, studies studies Recent have shown that food can play an important role in handling epilepsy, since the consumption of a high ketogenic diet in fat and low carbohydrates, among them we have the use of a diet enriched in medium chain triglycerides oil And coconut oil with a well tolerated palatability, seems to improve around 30% convulsions and behavior in some patients, it seems that these are metabolizes in the liver in ketone bodies, with high ketogenic performance, providing a source of energy that improves Brain metabolism improves the frequency of seizures by 88%, the severity of seizures by 61% and protection Against possible side effects in 65%, they could influence the pharmacokinetic properties of antiepileptic drugs and potentially modulate their efficacy and safety profile, so it is proposed that more research is carried out where its mechanism and monitoring by monitoring by part of veterinarians to improve the future management of idiopathic epileptic patients.