Ustekinumab Quantitation with Antibodies, Serum
Also known as: USTEK
Use
This test measures the trough level of ustekinumab in patients treated with the drug. It is used for therapeutic drug monitoring to ensure effective dosing and to assess the presence of antibodies against ustekinumab, which may impact the drug's efficacy. This is particularly relevant for managing treatment in conditions like inflammatory bowel disease, where maintaining appropriate drug levels is crucial for therapeutic success.
Special Instructions
Collect the specimen immediately before the patient's next scheduled dose of ustekinumab to ensure accurate trough level measurement.
Limitations
The test has a lower limit of quantitation of 0.3 mcg/mL for ustekinumab, meaning results below this level cannot be reliably measured. The presence of antibodies against ustekinumab can vary based on factors such as patient's immunological status and disease activity. Additionally, this test was developed by Mayo Clinic in accordance with CLIA requirements and lacks FDA clearance or approval, which may affect its recognition for certain regulatory purposes.
New York Approved
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 87408-1
- 87409-9
Result Turnaround Time
5-8 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.35 mL
Container
ARUP standard transport tube, serum separator tube (SST), or plain red tube
Patient Preparation
Collect immediately before next scheduled dose (trough).
Storage Instructions
Refrigerated transport preferred, freezing acceptable.
Causes for Rejection
Heat-inactivated specimens
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unacceptable |
| Refrigerated | 21 days |
| Frozen | 21 days |