Liquid chromatography-tandem mass spectrometric monitoring of whole blood concentrations of tacrolimus (previously known as FK506). Gold-standard assay for best management of dosage of Prograf and Advagraf used in immunosuppression.

Trl_110105

Varies widely with indication and patient characteristics but usually within the range 1 –12 µg/L.

For further advice: T 020 3299 3147

Pre-dose whole blood sample taken in EDTA (0.5mL minimum; 12h post-dose for bd dosing).

Please submit with a request form showing the last dose, last dose time and sample time/date.

Tacrolimus is stable in blood at normal ambient temperatures for at least one week. Ship adequately contained samples by 1st class mail or courier depending on urgency.

Send directly to:

IDM Service,

Institute of Liver Studies,

King’s College Hospital,

Denmark Hill,

London SE5 9RS

Same day Monday to Friday for samples received before 3 to 3.30 pm.

Same day for other immunosuppressants e.g. ciclosporin, sirolimus or mycophenolate in the same sample.

Interpretation is affected by indication for tacrolimus, time from start of therapy, immunosuppressant comedication and patient’s clinical condition. Results vary during co-medication with inducers and inhibitors of cytochrome P450 3A and P-glycoprotein and with liver function (see Purpose of the Test).

On application

IDM service:

E kch-tr.KCHIDMService@nhs.net

T 020 3299 3147

Brown et al. Clinical Chemistry 2005; 51: 586-592. (Tacrolimus measurements by LCMS and MEIA compared)

Ciclosporin - LC/MS

Everolimus

HBV DNA (quantitative)

HCV genotyping

HCV RNA (qualitative)

HCV RNA (quantitative)

HDV antibody (IgM)

HDV antibody (Total)

HEV antibody (IgG)

HEV antibody (IgM)

Liver biopsy

Mycophenolate – LC/MS

Sirolimus - LC/MS

Tacrolimus – LC/MS