NEUROPATHY - A.I.D.P
In this chapter, we will discuss about the diseases of the nerves, which originate from the brain and the spinal cord, and carry messages to the muscles of the face, neck, limbs, chest, stomach etc and take the sensory impulses from the skin and other sensory organs as well as important organs to the brain and the spinal cord. The nerves that carry messages to the muscles are known as motor nerves and the nerves that carry sensations from end organs towards brain are called sensory nerves. The initial part of the nerve emerging from spinal cord is called a radical. These radicals are again of two types; motor and sensory. The diseases of the radicals are known as radiculopathy. Whereas the diseases of the nerves mentioned earlier are known as peripheral neuropathy.
There are many types of peripheral neuropathies and the main ones are polyneuropathy, entrapment neuropathy, mononeuropathy, mononeuropathy multiplex etc. peripheral neuropathy occurs due to many diseases and various other causes.
Many neuropathies are primary where the neurological disease occurs on its own like hereditary neuropathy (HMSN-I to HMSN-VI) or A.I.D.P. There are other cases in which the neuropathy is secondary to other neurological disease or disease of any other system, e.g. neuropathy related to cancer or affliction of nerves occurring in long term diabetes. In some rapidly progressing neuropathies like A.I.D.P. immediate hospitalization may be required.
In mononeuropathy there is damage in the working of one or more different types of nerves, which ache together. In entrapment neuropathy one or more nerves are compressed somewhere in their routine pathway e.g. carpel tunnel syndrome in which the median nerve gets compressed at the root of the wrist.
In polyneuropathy, usually sensations decrease equally on both sides of the body, muscle power decreases and other problems like bowel and bladder problems also arise. Polyneuropathy is usually of two types:
1. Axonal Neuropathy in which there is tingling in thepalms and soles of the hands and feet, burning sensation, and the disease starts spreading upwards gradually weakening the muscles and reducing the sensations. Metabolic diseases like diabetes, diseases of the kidney, liver, vitamin deficiency, poisonous chemicals, heavy metals and side effects of medicines (some antibiotics, cancer chemotherapy, anti malarial.... etc) cause Axonal Neuropathy. This disease occurs gradually, is of long duration and difficult to cure.
2. Demyelinating Neuropathy : In this, abnormalityoccurs in the insulatory myelin sheath of the nerves. It can be considered a kind of allergy. Virus or other causes may damage the myelin sheath covering the nerves, disturbing the functioning of the nerves. Some neuropathies may occur quickly and recover quickly too, and some may even be life threatening like A.I.D.P. about which we will discuss in detail. Many neuropathies may recur after recovering. In many cases diseases of the muscles and nerves are seensimultaneously like Myotonic Dystrophy.In short one can say, that heredity, virus, cancer, side effects of medicines, disease of any part of the body, deficiency of nutritional elements, leprosy, diabetes - such various reasons can affect the nerves. In other words if the nerves are afflicted, it may be necessary to investigate systematically the entire body to find out the source of the disease and even then the exact reason cannot be found in 20 to 30% polyneuropathy cases, which is still a challenge to modern medical science.
1. A.LD.P. :means Acute Inflammatory Demyelinating Polyradiculoneuropathy. It is also known as G.B.S. or GuillainBarre Syndrome. In this disease,, forsome intricate reasons the nerves become weak. It first starts from the patient’s legs causing symptoms ranging from tingling and numbness in the legs with nominal weakness to paralysis of the limbs, some life threatening symptoms related to respiration may also be seen in patients of this disease. The inflammation of the nerves due to some reasons causes an increase in the proportion of .cells called Monocyte Macrophages. As a reaction to this, the coating of the nerves called myelin is destroyed resulting in the weakening of the nerves. It is believed that formation of antibodies against myelin starts the process of the weakening of the nerves.
The causes of the above mentioned reactions are not clear, although in 50% to 60% patients, viral infections of the throat, stomach or intestines precede the occurrence of A.I.D.P. In some patients the disease is seen occurring after taking the vaccine for rabies, tetanus and polio. A.I.D.P. can also occur in a few weeks after a minor surgery.
This disease can occur at any age, especially in the age group of 40 to 55 years. Not only this, research shows that a relation of this disease can also be established with particular seasons. The disease can be divided into 3 parts according to its intensity - mild, moderate and severe.
In the initial stage of the disease the patient experiences tingling in the feet, cramps, pain, or in many cases the patient may lose balance while walking. Both the legs get affected almost at the same time and as the weakness increases gradually both the legs and hands become completely paralyzed. This can happen in 2 -4 days or two to four weeks.
When the cranial nerves are affected, the facial muscles stop working. There is a change in the voice and difficulty in swallowing food. While drinking water, the water may come out through the nose and there may be difficulty in respiration. 10% of the patients suffer from life threatening respiratory problems. Such patients can be given artificial respiration through a ventilator.
The other symptoms of this disease include irregularity of the heartbeats and sometimes there may be low B.P. or profuse perspiration. There is a decrease in the sodium content of the blood. The patient remains completely conscious and a few may lose bowel and bladder control, but this happens rarely.
The primary neurological examination of the patient with the above mentioned symptoms could give important clues indicative of the diagnosis, in which mainly “TendonJerk” (the involuntary contraction of a muscle produced bystriking the tendon) is destroyed in this disease.
The second conclusive investigation is the C.S.F. test that shows an increase in protein levels (especially Ig G) but there are hardly any cells.
The tests called E.M.G., N.C.V. show a decline in strength and working of the nerves.
It is advisable for patients suffering from A.I.D.P. to be admitted to the hospital for the first 1 to 2 weeks. Since there is a difference of opinion regarding the indication of steroids like Methyl Prednisolone and A.C.T.H in the treatment of this disease, new drugs are being used in place of them.
In the Plasmapheresis therapy, 1500 to 3000 ml blood is taken from the patient’s body at a time and purified. The cells are separated with the help of a cell separator, purified, harmful antibodies are removed and the purified blood is transfused again in the body. This treatment can arrest the progress of the disease, prevent respiratory difficulties and speed up recovery. This method is carried out on alternate days for approximately five times.
Another more effective drug is Gamma globulin. Given intravenously, this drug neutralises harmful antibodies. This medicine is given for S days in a daily dose of approximately 20 to 30 grams (400mg/kg body weight). There are very few side effects of this drug. It can also be given to children as well as heart patients, but the treatment being very expensive ,makes it difficult for many patients to take advantage of this drug. A drug called Fucidine has also been found effective, in A.LD.P. patients. It is not so expensive but is still in the experimental stage.
Apart from treatment, A.I.D.P. patient has to take certain other precautions too. The patient should get proper nutrition, and care should be taken to prevent bedsores and infections. The doctor should be informed immediately if there is slightest respiratory distress. In emergency, the patient can be kept on a ventilator, which is expensive, but can save life. Besides, physiotherapy has been found to be extremely beneficial in this disease and is an important aspect of treatment. In the initial fifteen days if the disease is not progressing and especially there are no respiratory problems, the possibility of complete recovery is greater, though it may take months to get completely cured.