Alzheimer's disease

Alzheimer's disease is a progressive mental disorder that brings about changes in the brain slowly leading to dementia. Named after the German physician Alois Alzheimer, Alzheimer's disease has 2 characteristic neuronal changes : Loss of cholinergic cells in the basal forebrain and the development of neuritic plaques in the cerebral cortex. Neurofibrillary tangles can also occur due to Neuritic plaques.

Here the brain cells degenerate and die thus causing a decline in the mental functioning and memory of a person. Alzheimer's disease (AD) or Presenile dementia as it was earlier known as, is one of the primary causes of dementia. The levels of the brain neurotransmitters serotonin, norepinephrine and acetylcholine are found to be low in AD. This kind of brain disorder causes loss of social and intellectual skills of a person. In severe cases it interferes with the day-to-day activities of a person.

Alzheimer's disease causes

• Most scientists believe that Alzheimer's disease is caused due to increase in production and accumulation of a protein called beta-amyloid protein. The accumulation of this protein leads to nerve cell death.
  
• Environment factors that causes a change in the brain's functioning can also lead to Alzheimer's disease
  
• Genetic causes
  
• Abnormal levels of elements like aluminum and lead
  
• Chronic cerebrovascular condition resulting from high blood pressure can lead to cerebral microbleeds. These microbleeds over a long period can result in mild cognitive impairment.
  
• Head injury
  
• Some viruses
  
• Lifestyle changes that causes change in the brain's functioning can also lead to Alzheimer's disease
  
  

There are 4 major cognitive deficits arising out of AD :

1. Amnesia : Memory loss is probably the most common symptoms of Alzheimer' disease.
2. Aphasia : Loss of Language - Failure to recollect names of objects
3. Apraxia : Inability to perform voluntary movements
4. Agnosia : Inability to recognize people and places

• Forgetfulness, unusual difficulty in remembering things
  
• Mild confusion
  
• Occasional memory lapse
  
• Disorientation day, date, etc.
  
• Problem with speaking and writing
  
• Problem in thinking and reasoning
  
• Decision making problems
  
• Depression, anxiety, mood swing and many such behavioral problems
  
• Problems with cognitive skills like calculating, judgment, etc
  
  

Alzheimer's disease diagnosis

1. A physical examination and a neurological examination to check:

• Muscle tone and strength
  
• Sense of touch and sight
  
• Reflexes
  
• Balance
  
• Coordination, etc.
  

2. Brain imaging (CT scans, MRI) to check for tumors, etc.
3. Lab tests for thyroid etc so as to rule out other possibilities for memory loss

Treating Alzheimer's disease

As this disease is of degenerative nature, there is no permanent cure. Early diagnosis and changes in lifestyle can slow down its progression or improve the quality of life for the afflicted.

• Drugs to deal with cognitive changes and memory symptoms
  
• Drugs to increase acetylcholine or butylcholine levels. eg; Donepezil hydrochloride or rivastigmine, a cholinergic agonist or Cholinesterase inhibitor.
  
• Vitamin E combined with Cholinesterase inhibitors
  
• Alternate medicines like Ginkgo Biloba, Brahmi, Gotu kola, Ginseng and St. John's Wort
  
• Exercise
  
• Well balanced and nutritious food
  
• Lifestyle changes that help deal with and improve the current condition
  

CJD

This is a rare degenerative disease, a fatal brain disorder. One in every million worldwide is affected by Creutzfeldt Jakob disease which occurs about age 60, and about 90 percent of patients die within a year. Since first described in 1920, less than 1 percent of cases have acquired CJD.

Signs and symptoms

During the early stages of the disease failing memory, behavioral changes, lack of coordination and visual disturbances are exhibited. Impaired memory, judgment and thinking and insomnia, depression or unusual sensations are other symptoms. CJD may also cause fever or other flu-like symptoms. As the illness progresses, mental deterioration becomes severe. Involuntary movements, blindness and weakness of extremities are other symptoms.

Rapidly the disease progresses into dementia. Patients eventually lose the ability to move and speak and then enter a coma. Pneumonia and other infections may occur in these individuals and can lead to death. Some symptoms of CJD can be similar to Alzheimers or Huntington disease. CJD causes unique changes in brain tissue which can be seen at autopsy and the deterioration is more rapid than Alzheimer's disease or other types of dementia.

Major categories of CJD

Sporadic CJD: Here the disease appears even though the person may not exhibit any known risk factors. This is by far the most common type of CJD and 85 percent cases come under this category.

Variant CJD is caused by consuming meat from a cow that had Bovine Spongiform Encephalopathy (BSE) or mad cow disease, a prion disease similar to CJD. Strict controls have proved very effective since its discovery in 1996.

In hereditary CJD, the person has a family history of the disease and tests positive for a genetic mutation associated with CJD. About 5 to 10 percent of cases in the US are hereditary and the symptoms usually develop in early 50s.

In latrogenic CJD, the infection spreads from someone through medical or surgical treatment. A common instance of this is spread of CJD from someone with growth hormone treatment using human pituitary growth hormones extracted from deceased individuals who might have had CJD infection.
CJD is not contagious through casual contact with a CJD patient.

Causes

Researchers believe that an unusual slow virus or any other organism causes CJD. But they have never been able to isolate a virus or any organism in people with the disease. As the agent causing CJD has several characteristics other than known organisms such as bacteria and virus, it is difficult to destroy as it does not contain any genetic information in the form of nucleic acids. For example, prions are not destroyed by the extremes of heat and radiation used to kill bacteria and viruses, and antibiotics or antiviral medicines have no effect on them. It also incubates for a long period of time before the symptoms appear, as long as even 50 years. The leading scientific theory maintains that CJD is caused by a type of protein called as a prion. Also 5 to 10 percent of CJD cases are inherited. These cases arise from a mutation, or change in the gene that controls formation of the normal prion protein.

Diagnosis of CJD

There is no single diagnostic test for CJD. First, all treatable forms of dementia are ruled out. A neurological examination is performed and consultation with other physicians is sought. Spinal tap, electroencephalogram, CT and MRI and brain scans can reveal characteristic patterns of brain degeneration that can help diagnose CJD.

For a confirmed diagnosis of CJD, brain autopsy is the only way. A neurosurgeon removes a small piece of tissue from the patient's brain and it is examined by a neuropathologist. The procedure may be dangerous as it does not always obtain tissue from the affected part of the brain. Brain biopsy is discouraged unless it is needed to rule out a treatable disorder. In autopsy, the whole brain is examined after death. Special surgical and disinfection procedures can minimize the risk. Scientists are working to develop laboratory tests for CJD.

As such there is no treatment or cure to control CJD. Studies are on to try a variety of drugs but none of the treatments have shown consistent benefits in humans. Treatment aims at alleviating symptoms and making the patient as comfortable as possible. Opiate drugs can help relieve pain. During later stages of the disease, changing person's position frequently can keep them comfortable and help prevent bed sores. A catheter is used to drain urine if bladder control is lost. Intravenous fluids and artificial feeding are also used.

Avoid spreading CJD

To reduce the very low risk of CJD transmission from one person to another, it is better not to donate blood, tissues or organs if suspected or confirmed with CJD because of family history of the disease. As normal sterilization procedures such as cooking, washing and boiling do not destroy prions, the following precautions are suggested by the World Health Organization while dealing with patients contacted with CJD.

• Cuts and abrasions should be covered with waterproof dressings.
  
• Surgical gloves should be worn when handling a patient's tissues and fluids or dressing up patient's wounds.
  
• Avoid cutting or sticking with instruments contaminated by patient's blood or tissues.
  
• Use disposable bedclothes for contact with patient.
  
• Use face protection if there is risk of splashing contaminated material such as blood or cerebrospinal fluid.
  
• Soak instruments that have come in contact with patient in undiluted chlorine bleach for an hour or more and then autoclave to sterilize them in distilled water for at least one hour at 132-134 C.

Convulsions

Seizures or convulsions are associated with the electrical activity of the brain. They have an impact on major systems of the body and can be fatal if not treated. Seizures are classified predominantly based upon their site of occurrence and the affected organ or system.

Types of Convulsions

General or clonic seizures: In most cases, generalized seizures are also called as tonic-clonic seizures as they involve the entire body. In common parlance, it also referred as epileptic attacks. Patients experience changes in sensations such touch, taste, smell and vision. Hallucinations or auras are also experienced as they begin to influence the emotional balance of a person.

Focal or Partial seizures: These types of seizures are cause because of disturbed electrical activity in the brain which is localized to one part of the brain. It acts on the temporal region of the brain leading loss of memory and balance in extreme conditions.

Petit mal Seizures: These are temporary and their effects are usually limited to 20 seconds. They generate temporary muscle spasms which happen because of electrical imbalances in the brain.

Epilepsy: This type of seizure is closely related to general seizures. The factors associated with the onset of epilepsy may include preexisting conditions such as ischemic heart disease, Alzheimer disease, meningitis and encephalitis.

Fever induced convulsions: These types of seizures predominantly occur in children, infants and toddlers. The initial phase of these convulsions is very intense as they cause much discomfort to the child. They usually subside within a few hours. Most of the fever induced convulsions are caused by viruses and ear infections.

Clinical manifestations

Most convulsions or seizures are characterized by classical muscle spasm symptoms which includes rigorous shaking and frothing with prolonged effects like unconsciousness (blackout). Since the predominant reason associated with convulsions are related to the electrophysiology of the brain, neurological symptoms such as confusion, hallucination, dementia, drooling, lack of bladder control and sudden loss of balance may also be noticed.

Convulsions also have effects on the emotions of a person as many people complain of unprecedented symptoms such as sudden aggression, depression, mood swings, panic, extreme laughter and joy for a temporary period of time. Warning signs often appear before any form of seizure such as dizziness, sensitivity to light, vertigo and nausea.

Seizures can also occur as a result of withdrawal from use of drugs such as barbiturates, valium or benzodiazepines. Drug abuse and alcohol abuse along with preexisting health complications such as end-stage renal disease, renal failure and congenital heart disease can indicate high percentage of seizure onset. Seizures also occur in conditions such as Steven Johnson syndrome, a disease occurring in children. In addition to these clinical manifestations, seizures can occur because of severe brain injury, shock or even during athletic events as result of extreme adrenaline levels in the blood.

Diagnosis and Treatment

Epileptics are diagnosed with a meticulous examination of their history. Various biochemical tests such as sodium levels, SGOT, SGPT and blood glucose levels are analyzed. Electro encephalogram is done to understand the electrophysiology of the brain. In some cases, neurologists recommend MRI and CT scans to understand the presence of any abnormalities or to identify any kind of trauma caused in the brain or the spinal cord.

In most cases seizures are treated with antidepressants as the predominant cause of any form of seizure is depression. Anti epileptic drugs such as sodium channel blockers and GABA transaminase inhibitors are recommended.