Cyclosporin

Keywords: Cyclosporin measurement

Specimen:

5 mL blood in EDTA tube, usually taken at 2 h post dose. Additional time points are sometimes required.

Method:

Immunoassay or HPLC.

Therapeutic Interval:

Depends on method and on the indication for therapy.

There is a wide variation in the therapeutic intervals recommended by different institutions. The following is an approximation only.

Organ transplant - kidney
Time post transplant: < 6 months; Cyclosporin levels: 250-350 µg/L
Time post transplant: > 6 months; Cyclosporin levels: 100-200 µg/L.

Organ Transplant - Liver
Time post transplant: < 1 month; Cyclosporin levels: 350-450 µg/L
Time post transplant: 2-6 months; Cyclosporin levels: 250-350 µg/L
Time post transplant: > 6 months; Cyclosporin levels: 170-240 µg/L.

Organ Transplant - Heart
Time post transplant: < 6 weeks; Cyclosporin levels: 350-450 µg/L
Time post transplant: 6-12 weeks; Cyclosporin levels: 250-350 µg/L.

For bone marrow transplant, the therapeutic intervals vary with the type of transplant, that is allogeneic, unrelated, or syngeneic.

The role of therapeutic monitoring is less well established in autoimmune disease; monitoring is only indicated if high doses of cyclosporin are used.

Application:

Maintenance of therapeutic levels of cyclosporin in patients receiving immunosuppressive therapy, usually to avoid rejection of organ transplants.

Detection of toxic levels.

Consult pathologist.

Interpretation:

An elevated result provides an early indication of the possibility of toxicity.

Reference:

Keown PA. Curr Opin Nephrol Hypertens 2002; 11(6): 619-626.

Andrews DJ and Cramb R. Ann Clin Biochem 2002; 39(Pt 5): 424-435.