| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Infliximab Level and Anti-Drug Antibody
Test Code36311
CPT Codes
82397, 80230
Preferred Specimen
0.8 mL serum
Patient Preparation
Dietary supplements containing biotin may interfere in assays and may skew results to be either falsely high or falsely low. For patients receiving the recommended daily doses of biotin, draw samples at least 8 hours following the last biotin supplementation. For patients on mega-doses of biotin supplements, draw samples at least 72 hours following the last biotin supplementation.
Collect immediately before next scheduled dose (trough specimen).
Minimum Volume
0.5 mL
Transport Temperature
Refrigerated (cold packs)
Specimen Stability
Room temperature: 48 hours
Refrigerated: 7 days
Frozen -20°C: 28 days
Frozen -70°C: 70 days
Refrigerated: 7 days
Frozen -20°C: 28 days
Frozen -70°C: 70 days
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Moderate and gross hemolysis
Methodology
Chemiluminescent Immunoassay
FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.
Setup Schedule
Set up: Mon, Tues, Thurs-Sat; Report available: 4-6 days
Reference Range
| Infliximab Level | See Laboratory Report |
| Infliximab Ab | <38 AU/mL |
Clinical Significance
Infliximab is a therapeutic monoclonal antibody with the ability to bind to tumor necrosis factor (TNF), an inflammatory cytokine, blocking its action. Infliximab is indicated for the treatment of Crohn's disease, ulcerative colitis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, plaque psoriasis, and juvenile idiopathic arthritis. Trough concentrations of infliximab correlate with the likelihood of clinical remission, but the role of routine monitoring is not clear. Target concentrations may depend on indication, induction vs. maintenance, dosing schedules, drug clearance, and other factors. Infliximab is immunogenic and a significant percentage of treated patients develop antibodies. In these patients, antibodies may be associated with lower trough levels of the drug. Measuring both drug level and antibody may help manage patients with an inadequate clinical response. If drug concentrations are low and antibody levels are also low, drug optimization may be necessary. If drug concentrations are low and antibody levels are high, switching to another class of biologic agents may be necessary.
Performing Laboratory
| Quest Diagnostics Nichols Institute-San Juan Capistrano, CA |
| 33608 Ortega Highway |
| San Juan Capistrano, CA 92675-2042 |
