What is being tested?This test measures the amount of cyclosporine in the blood. Cyclosporine is an
immunosuppressive drug used to dampen the body’s natural defenses. When patients undergo an organ transplant, their immune system recognizes the graft as a foreign substance and will begin to attack it just as it would any invasive bacteria or virus. Cyclosporine affects the ability of certain white blood cells in the immune system to respond to this foreign tissue. The transplanted organ then has a better chance of survival and will not be as easily rejected by the patient’s system. Cyclosporine is used routinely in the transplantation of kidney, heart, liver, and other organs.
The immunosuppressive qualities of cyclosporine have also been found to be useful in treating symptoms of some autoimmune and other disorders. These conditions are characterized by the immune system reacting to the body’s own cells or tissue. Cyclosporine helps to control the immune response in these cases, decreasing the severity of symptoms. Some examples include rheumatoid arthritis, psoriasis, aplastic anemia, and Crohn’s disease.
When the symptoms in these cases are judged to be severe, extensive, and disabling, cyclosporine may be prescribed. Usually, the symptoms have not responded well to other treatments or medications. Cyclosporine is used with caution in these cases and needs to be carefully monitored with blood tests.
Testing cyclosporine levels in the blood can help ensure that drug levels are in a range that will be therapeutic for you. If the level is too low, organ rejection may occur (in the case of transplantation) or symptoms may reappear (autoimmune cases). It is also important to ensure levels are not too high and will not result in toxicity.
