What is CIDP?
Obviously suppressing the immune response cannot be undertaken lightly because it runs the risk of suppressing normal immune responses to infections. The decision whether to try these treatments has to be tailored by your doctor to your individual needs. However it is reassuring to know that treatments are available, that demyelinated nerves can repair themselves, and that some patients get better without treatment.
Due to the small number of patients and because most of the treatment methods are quite new, there is limited evidence available of the relative effectiveness of different treatments. Some patients respond to one method and not to others. There is only a very unfortunate few that cannot be helped by any of these treatments.
Controlled trials have demonstrated that cortisone-like steroid are beneficial in CIDP. This group of drugs, which includes Prednisolone, is similar to the normal cortisone made by the adrenal gland as part of the normal mechanisms for coping with stress. A wide range of dosage schedules has been used and no work has been addressed to the question of which is best.
The high risks of serious side effects resulting from the prolonged use of high dose steroids are well known. These include osteoporosis (thinning of bones), cataracts, diabetes, hypertension (raised blood pressure), obesity and myopathy (muscle weakness). Steroid treatment also suppresses your normal production of cortisone, sometimes for up to a year after stopping. If you are undergoing stress such as an operation, your anaesthetist needs to know, as extra cortisone may need to be injected at the time. If the dosage levels required to control CIDP appear unacceptably high or unacceptably prolonged, it may be suggested that other immunosuppressive drugs be used.
Clinical evidence suggests that immunosuppressive drugs help. These include Azathioprine, Cyclo-phosphamide and Cyclosporin. Azathioprine is the most widely used in the treatment of CIDP. Regular blood tests (such as blood count, liver or kidney function) are required to check for side effects that can be avoided by stopping these drugs or reducing the dose. In addition, the use of these drugs carries the theoretical side effect of increased risk of developing cancer, but in practice this increased risk is very small.
Plasma exchange involves being connected to a machine which can separate the blood cells from the fluid or plasma. In an on-line process, blood is continuously taken from the patient, separated, the plasma is discarded, the blood cells are mixed with clean plasma (which has been collected from blood donors) and returned to the patient. (The process is not unlike that used in kidney dialysis). At each session about two or three litres of plasma are exchanged. The procedure is usually repeated several times over about two weeks until sufficient plasma has been exchanged. The procedure is safe and the risks are small. It is uncomfortable but not painful, however some patients find that it leaves them feeling tired for a day or two.