Mycophenolic Acid Drug Level
Label Mnemonic: MYCPHN
Epic code: LAB3666
Downtime form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
Commercial Mailout Laboratory
6240-8 RCP
356-8593
Specimen(s):
Serum
Collection Medium:
Red top tube 5 mL (Clot Activator)
Minimum:
Preferred Minimum: 1 mL serum
Absolute Minimum: 0.25 mL serum
Rejection Criteria:
Serum gel tube is not acceptable.
Turn Around Time:
3 days upon receipt at reference laboratory
Reference Range:
MYCOPHENOLIC ACID
   1.0-3.5 mcg/mL

MPA GLUCURONIDE
   35-100 mcg/mL
Interpretive Data:
Trough serum levels of MPA at steady-state (>2 weeks at the same dose) in the range of 1.0-3.5 ug/mL indicate adequate therapy. MPA-G levels in the range of 35-100 ug/mL indicate that the patient has normal UGT metabolic capacity. MPA-G levels are typically in the range of 100-250 ug/mL during the 2 weeks following transplantation. MPA-G typically decreases after this initial post-transplant phase.

Trough steady-state serum MPA levels >4.0 ug/mL indicate that the patient is overimmunosuppressed and susceptible to systemic infections. Decreased dosages may be indicated in these cases.
Comments:
The principle clinical problem encountered in MPA therapy is excessive immunosuppression, which predisposes the patient to systemic infection. Measurement of the blood level of MPA and MPA-G can be useful to guide therapy.

Monitoring is recommended immediately after transplant up to 3 weeks after therapy is initiated to evaluate dosing adequacy. Additional monitoring is indicated if the MPA level is not in the therapeutic range or if a major change in health status occurs.

Cautions:
Correct interpretation requires a trough serum specimen (just before the next regular dose). Specimens drawn at other times in the dosing cycle are likely to have higher MPA levels. In these cases, the reference range does not apply.
Methodology:
Tandem Mass Spectrometry (MS/MS)
CPT Code:
80180