Specimen requirement

Adult patient:

EDTA tube

Minimum blood volume: 3 mL

Paediatric EDTA tube

Number of vials: 1

Minimum blood volume: 1.3 mL

Authorisation code required

No

24 Hr available service

No

Collect full tube of blood and mix thoroughly.

Label the specimen with the correct time point of collection:

C2 = 2 Hr post-dose

C0 = trough (pre-dose)

Consult duty biochemist if other time points are required.

Method

Liquid chromatography-tandem mass spectrometry

Reference interval

Cyclosporin (C2):

Post-Tx	Kidney	Liver
< 1 month	1,600	-
< 2 months	1,400	-
< 3 months	1,200	-
< 6 months	1,000	900
< 12 months	800	700
> 12 months	700	500

(Source: modified from Bio Drugs 2001; 15: 279 - 90)

Cyclosporin (C0):

Post-Tx	Kidney	Liver
< 1 week	230 - 300	230 - 470
< 1 month	200 - 300	150 - 350
< 3 months	150 - 230	150 - 270
< 6 months	70 - 150	150 - 230
< 1 year	70 - 100	110 - 200
< 2 years	70 - 100	-

(Source: modified from Clin Chem 1990; 36: 1,841 - 6)

Clinical indication

Therapeutic drug monitoring in patients receiving cyclosporin A therapy to avoid rejection of organ transplants and to detect toxic levels.

Result interpretation

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

Measurement of uncertainty

See table.

Frequency of measurement

Daily