Cyclosporine
Norm (depends on the manufacturer’s recommendations)
Induction
after kidney transplant 150–250µg/l
after liver transplant 150–300µg/l
after heart transplant 250–300µg/l
Maintenance dose
after kidney transplant 100–200µg/l
after liver transplant 100–250µg/l
after heart transplant 150–300µg/l
Toxic concentration more than 400µg/l
Synonyms: Sandimmune®.
Blood EDTA
Cap violet
Cyclosporine is one of the best immunosuppressants that needs to be taken continuously after organ transplantation. For cyclosporine testing, blood should be drawn 12–18 hours after oral drug intake (maintenance phase), 12 hours after intravenous administration, or just before a regular dose.
Cyclosporine pharmacokinetics show high variability. The drug concentration in the blood depends on individual characteristics, metabolic activity, liver, and kidney function. When taken orally, on average 28% of the drug enters the blood (variation from 3% to 98%). 1–8 hours after a single oral dose, the maximum concentration is reached in the blood. During the induction phase of treatment, a certain concentration in the blood must be achieved and maintained during the first three months after organ transplantation. Later, the drug concentration is reduced to the maintenance dose, and the level of cyclosporine in the blood must meet the requirements of the maintenance period concentration (if liver and kidney function is normal). The concentration of cyclosporine in the blood fluctuates the most after liver transplantation.
Cyclosporine is the main drug used in organ transplant surgeries. It effectively reduces immune rejection reactions and prolongs the functioning time of the transplanted organ. The results of transplantation before and after the discovery of cyclosporine are significantly different. Nowadays, in countries with advanced transplantology, about 90% of kidneys function for more than a year after the transplant surgery. After heart transplantation, 80% of patients live for a year. Modern transplantology cannot be imagined without the continuous use of this medication. Excessive concentration of cyclosporine in the blood is dangerous because it can lead to infectious complications and damage to parenchymal organs. Too low a dose of this drug in the blood is also dangerous because the immune response can reject the transplanted organ. This happens when doses of the drug are too low to sufficiently weaken the immune system. Several drugs similar to cyclosporine are currently being studied in clinics. Their therapeutic monitoring commercial tools are also starting to be used: FK 506, Prograf®, Tacrolimus®, Sirolimus, Rapamune®, Rapamycin®.
Various schemes may be recommended for transplantation: cyclosporine; cyclosporine with prednisolone; cyclosporine, prednisolone, and azathioprine. Drugs that increase cyclosporine toxicity: aminoglycoside antibiotics, cephalosporins, trimethoprim, amphotericin B, acyclovir, ketoconazole, furosemide. Drugs that increase cyclosporine serum concentration: methylprednisolone, cimetidine, erythromycin. Drugs that decrease cyclosporine serum concentration: phenobarbital, phenytoin, rifampicin, trimethoprim.
Source | Handbook of Basic Laboratory Tests | Doctor of Medical Sciences Gintaras Zaleskis