Pathophysiology of Epilepsy
Pathophysiology of Epilepsy
Epilepsy is defined as a common and diverse combination of disorders which may be chronic or neurological and are characterized by seizures. It is basically a behavior spell which is caused by excessive discharge (disorderly) of cortical cells of the nerves in the brain. These are diverse comprising of undetectable seizures, to clearly visible convulsions. These seizures may be recurrent and occur naturally without being provoked, or some may be independent with only a single step in brain alteration as cited by Sudha 1. Epilepsy is classified by: etiology (first cause), semiology (observance of seizure manifestations), the area in the brain where the seizure starts, using discrete medical syndromes, by analyzing the occasion which triggers the seizure. Types include: simple, complex, absence, myoclinic, tonic-clonic and atonic types of seizures
Causes of epilepsy
In most cases, the exact cause is unidentifiable. However, factors which are associated with causing epilepsy include brain tumor, brain cancer, misuse of drugs and alcohol, and strokes among other factors. In certain cases, they can be analyzed as either those which occur spontaneously or those that are just triggered by small occurrences, such as reflex epilepsy as based from Sudha’s argument 2. A good example of reflex epilepsy is in patients who have reading epilepsy, where the seizures occur when the subject is reading. Children who have childhood absence epilepsy may be vulnerable to hyperventilation (although hyperventilation together with flashing lights is procedures are used to trigger seizures during diagnosis). In women who are epileptic, the menstrual cycle may be an influence to occurrence of a seizure. Seizures triggered by the menstrual cycle are referred to as catamenial epilepsy. Other causes include emotional stress, heat stress, and lack of enough sleep as based from Sudha’s argument 3.
Acute seizures are caused by the interactions between albumin (blood protein) and astrocytes and the disruption of the blood brain barrier by either inflammatory or artificial methods Sudha 3(p 12). The various triggers of epilepsy are common in certain age classes; during early childhood. Epilepsy results to trauma and central nervous infections when the patient is in childhood stages. Well developed epilepsy syndromes occur in the adolescence stage due to, stress, traumas, brain tumors, misuse of drugs and alcohol. These activities are well known triggers in adolescents and adults as reported by Sudha 3(p 19). In old age, the causes of epileptic seizures are celebrovascular disease and degenerative diseases such as dementia Sudha 4.
Signs and symptoms of epilepsy
The symptoms depend on the type of seizure and also the section of the brain where the seizure occurs. Signs of simple seizures include states of unconsciousness, motor, psychic,sensory and autonomic signs. Motor signs include movement of the eyes and the turning of the head to the same side, sudden lack of speech and vocalization, alternative relaxation and contraction of muscles. Sensory signs consist of patient experiencing foul odors and tastes, dizziness and lightheadedness and hallucinations as observed by Sudha5 .Psychic signs include: being in a dreamy state, depersonalization, distortion of time, sudden and unprovoked emotions such as pleasure, fear, and anger among other emotions. Autonomic signs include: rumbling noises in the stomach, nausea and vomiting, pupilary dilation, abnormally fast heartbeat rate and goose bumps. Signs and symptoms of complex seizures include: Loss of consciousness and while in this state, the patient may have scared look of expression and also may pose other signs of simple seizures as cited by Kanner1 (pg17).When unconscious, automatism may occur in the following ways; chewing and excessive production of saliva, repetitive hands movement, running wildly and use of repeated word phrases.
There are other types of seizures such as tonic-clonic seizures which develop from simple and complex seizures. In this type, the patient will not remember this phase (tonic). Signs include loss of consciousness, falling, yelling and also autonomic symptoms as discussed above.Kanner2 .The next phase is the clonic one where; muscles relax and then suddenly contract causing the body to move in rhythmic jerky positions and after these jerky movements cease, the person may be unconscious for a while and later wake up disoriented. Kanner3 (pg 32)
Symptoms of absence seizures normally affect children. There is blank staring, changes in the facial expressions, and lack of responsiveness and loss of memory. There are also myoclinic seizures which are brief seizure characterized by muscle contractions and loss of consciousness although they are so brief such that it may not be known that consciousness is lost
Pathophysiology of epilepsy
These are the changes that occur in body cells both intracellular and extracellular. Gene mutations are associated with various types of epilepsy. Some forms of inherited epilepsy are caused by the mutations of genes that code for sodium channel proteins which may stay too long as open hence triggering excitement of the neuron hyper. This causes excessive release of glutamate and excessive release of calcium and this becomes neurotoxic to the affected cells. The hippocampus is highly vulnerable to epileptic seizure and even possible neuronal death as cited by Kanner4. There also exist epilepsy-related mutations in non-ion channel genes. Epileptogenesis is the process where the brain develops epilepsy slowly over a period of time due to strokes, trauma or lesions on the brain. Kanner5
The above analysis discusses the pathophysiology of epilepsy and the causes and the signs and symptoms puts to light the effects of epilepsy. The different forms of seizures discussed in the essay above show that epilepsy can affect anybody regardless of age and sometimes it is natural such as hereditary conditions. In conclusion, patients suffering from epilepsy should always be monitored regularly and having a person look after them at almost all times is important because seizures occur suddenly and the patient might lose consciousness. Currently there is no acute cure for epilepsy but there are control mechanisms for this condition which affects all age-groups.
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