PATHOPHYSIOLOGY OF EPILEPSY
Introduction
Epilepsy is a brain disease that collects neuron in the brain leading to abnormal effects. Basically, neurons make electro-chemicals impulses that act on muscles, gland and on other neurons to generate feelings, thoughts and action in human. The normal pattern activities of the human nerve cells are distorted during epilepsy, resulting in strange emotions, consciousness and behavior. In the severe cases, loss of consciousness, convulsion and muscle spasms may result. During a seizure, nerve cells can generate impulses as many as 500 in one second, which is much higher than the normal rate[1] . The rate differs among people as for some people it happens occasionally while on others it may occur frequently in a day. A person with severe seizure may wail, fall down unconscious or may be unable to control the urinary system. Epilepsy attack end in minutes and the victim recovers. However, the patient is always very confused and fatigued. A seizure arises when nerve cells in the brain produce rapid impulses cause sudden, uncontrollable activities of the brain cells. The systematic communication between nerve cells is disrupted causing the feelings; movement and thought of the victim become confused and uncontrolled in a short period of time.
Causes of epilepsy
The causes of epilepsy differ with the age at which the seizures begin and the nature of the seizures. The cause of most cases of epilepsy is not yet found. The only known cause involves brain injury. The brain is made of delicate neurotransmitters which include nerves cells, chemicals and impulses. There are three types of epilepsy namely symptomatic, cryptogenic and idiopathic epilepsy. The cause of epilepsy of a person is known in symptomatic epilepsy for instance head damage is a well known cause. Cryptogenic epilepsy has no apparent cause but the available evidence links it with head injury. Idiopathic epilepsy has no known cause despite all the research done. Notably, annually there are about 180,000 new cases of epilepsy[2]. Children and the elderly people are prone to the disease.
There are factors that have been identified to provoke seizures in people who have epilepsy which include heavy consumption of alcohol which interact with the anti-epilepsy drugs in particular ways. Alcohol reduces the effectiveness of anti-epilepsy drugs increasing the likelihood of the occurrence of seizures. Excessive consumption of alcohol can lead to poor control of seizure as a result of sleeping late night, poor feeding schedule and at time the patient may forget the dosage result in more seizures. Secondly, infections and illness particularly in children are likely to cause more seizures after developing infections such as earache and tonsillitis. Allergies in some people provoke seizures. Vomiting and diarrhea trigger seizure because anti-epilepsy drugs are not absorbed into the body. Thirdly, the other common factor that triggers seizures is the lack of sleep as a result of fluctuation. Fourthly, women have more seizure before and during menstrual periods[3]. These seizures result from the combination of factors such as alteration of the hormonal level, increased fluid withholding and anti-epilepsy level in the blood vessels. Catamental epilepsy result during this time.
Skipping medication by sensitive people increases the chances for the occurrence of seizures. Long break between dosages, lowers the blood level in the body increasing the chances of having seizures. In addition, extreme stress lowers seizure threshold and trigger seizures.
Pathophysiology of Epilepsy
The concentration of ion in both inside and outside the nerve cells change during epileptic seizures. This is due to the abnormal change of ion flow from and into the neuron. Basically, the concentration of sodium in the intracellular is lower that of the extracellular. However, the concentration of potassium in the extracellular is lower than that of intracellular. During a seizure, sodium ions move from the extracellular space into the neurons, while potassium ions move from the neurons to the extracellular space. The continuous and the increase in sodium concentration in the intracellular cause the termination of the seizure. Anti-epilepsy drugs slow down the rate of sodium buildup in the intracellular and prolong the duration of seizures. Chloride ions increase in the intracellular terminates seizure and prevents the sudden release of electro-chemicals in nerve cells. Notably, the occurrence of seizure depends on the movement of ion that occur on the surface of neurons[4].
Sign and symptoms of epilepsy
The type of seizure and the part of the brain in which they occur determines the sign and symptoms of epilepsy. I will discuss the signs and symptoms in simple and complex partial seizures. In simple partial seizures, symptoms include sensory, motor, conscious state and the involuntary activities that are controlled by the autonomic nervous system. In simple partial seizures there is no impairment of consciousness. Most of the symptoms are stereotypical. Motor signs include speech arrest, alternating relaxation and contraction of muscles and asymmetrical posture of the limbs[5]. Sensory symptoms of epilepsy include dizziness, hallucinations, experiencing unpleasant tastes and odors. Sign and symptoms of autonomic include profusely sweating, vomiting, flushing, rapid heart rate, flushing and papillary dilation. Conscious state symptoms include withdrawal, hallucinations, time disruption and having unprovoked emotions such as anger, fear, unhappiness and elation.
Complex partial seizures
Seizure result in loss of consciousness and the patient may have a frightened look. During the state of unconsciousness automatisms may occur[6]. The automatisms include the following
- Gestural appearance which includes the continuous movement of the hands and fingers
- Verbal automatism such as swearing and short phrased sentences
- Alimentary automatism such as increased salivation and rumbling noises that emanates from intestinal gas
- Ambulatory automatism such as running and wandering
- And mimetic automatism which includes laughter, an expression of fear and discomfort.
Patients with long term seizure may develop drop attacks. After the occurrence of drop attack patients lose tone and unconscious fall suddenly.
Conclusion
Epilepsy can be controlled through the use of the anti-epilepsy medications. The patient should avoid lifestyle that may result in increased seizure and should follow the instruction to reduce seizure occurrence. More research needs to be carried out to determine the cause of the disease and this may probably lead to a cure for the disease.
Reference
Johannessen Landmark C. Antiepileptic drugs in non-epilepsy disorders: relations between mechanisms of action and clinical efficacy. CNS Drugs [serial online]. 2008;22(1):27- 47. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
Meacham J. A storm in the brain. Newsweek [serial online]. April 20, 2009;153(16):38-41. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
Nesbitt V, Kirkpatrick M, Pearson G, Colver A, Forsyth R. Risk and causes of death in c hildren with a seizure disorder. Developmental Medicine & Child Neurology [serial online]. July 2012;54(7):612-617. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
Singhi P. Infectious causes of seizures and epilepsy in the developing world. Developmental Medicine & Child Neurology [serial online]. July 2011;53(7):600-609. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
Solomon N, McHale K. An overview of epilepsy in children and young people. Nursing Children & Young People [serial online]. July 2012;24(6):28-35. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
Whatley A, DiIorio C, Yeager K. Examining the relationships of depressive symptoms, stigma, social support and regimen-specific support on quality of life in adult patients with epilepsy. Health Education Research [serial online]. August 2010;25(4):575- 584. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
Zeqiraj K, Shatri N, Kruja J, Blyta A, Isaku E, Dakaj N. Epileptic Seizures in Multiple Sclerosis Patients. Turkish Journal Of Neurology / Turk NorolojiDergisi [serial online]. June 2013;19(2):40-43. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
[1] Meacham J. A storm in the brain. Newsweek [serial online]. April 20, 2009;153(16):38-41. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
[2] Singhi P. Infectious causes of seizures and epilepsy in the developing world. Developmental Medicine & Child Neurology [serial online]. July 2011;53(7):600-609. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
[3] Zeqiraj K, Shatri N, Kruja J, Blyta A, Isaku E, Dakaj N. Epileptic Seizures in Multiple Sclerosis Patients. Turkish Journal Of Neurology / Turk NorolojiDergisi [serial online]. June 2013;19(2):40-43. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
[4]Johannessen Landmark C. Antiepileptic drugs in non-epilepsy disorders: relations between mechanisms of action and clinical efficacy. CNS Drugs [serial online]. 2008;22(1):27- 47. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
[5] Solomon N, McHale K. An overview of epilepsy in children and young people. Nursing Children & Young People [serial online]. July 2012;24(6):28-35. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
[6] Whatley A, DiIorio C, Yeager K. Examining the relationships of depressive symptoms, stigma, social support and regimen-specific support on quality of life in adult patients with epilepsy. Health Education Research [serial online]. August 2010;25(4):575- 584. Available from: CINAHL Complete, Ipswich, MA. Accessed November 13, 2013.
