Test Details
Methodology
Electrochemiluminescence Immunoassay (ECLIA)
Result Turnaround Time
5 - 10 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Test Includes
This test includes serial monitoring.
Use
Provides infliximab drug concentration levels as well as levels of anti-infliximab antibodies.
In the absence of anti-infliximab antibodies, the infliximab drug level typically reflects the total infliximab concentration in serum. In the presence of anti-infliximab antibodies, the infliximab drug level typically reflects the antibody-unbound fraction of infliximab concentration in serum. The presence of infliximab drug, even at concentrations well above target treatment levels (>50 ug/mL), does not interfere with the anti-infliximab antibody detection. This assay may be helpful for any patients on infliximab therapy for diseases such as Crohn's disease, inflammatory bowel disease, ulcerative colitis, rhematoid arthritis, or other autoimmune conditions. This test includes long-term serial monitoring of results.
Limitations
Failure of infliximab therapy may not always be due to the presence of anti-infliximab antibodies. In addition, the absence of anti-infliximab antibodies does not guarantee positive response to treatment.
High serum biotin concentrations in patients taking biotin supplements may cause an interference in this assay. Patients may be advised to stop biotin consumption at least 72 hours prior to sample collection.
Failure of infliximab therapy may not always be due to the presence of anti-infliximab antibodies. In addition, the absence of anti-infliximab antibodies does not guarantee positive response to treatment. |
Failure of infliximab therapy may not always be due to the presence of anti-infliximab antibodies. In addition, the absence of anti-infliximab antibodies does not guarantee positive response to treatment. High serum biotin concentrations in patients taking biotin supplements may cause an interference in this assay. Patients may be advised to stop biotin consumption at least 72 hours prior to sample collection. |
Specimen Requirements
Specimen
Serum (preferred) or plasma
Volume
2 mL
Minimum Volume
1 mL (Note: This volume does not allow for repeat testing).
Container
Red-top tube, gel-barrier tube or plasma from green-top tube
Collection Instructions
Send serum in a plastic transport tube. To avoid delays in turnaround time when requesting multiple test on frozen samples, please submit separate frozen specimens for each test requested.
Stability Requirements
| Temperature | Period |
|---|---|
| Room temperature | 7 days |
| Refrigerated | 7 days |
| Frozen | 359 days |
| Freeze/thaw cycles | Stable x6 |
Storage Instructions
Frozen (preferred) or refrigerated
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 503870 | Infliximab Drug + Antibody | 503772 | Infliximab Drug Level | ug/mL | 39803-2 | |
| 503870 | Infliximab Drug + Antibody | 503773 | Anti-Infliximab Antibody | ng/mL | 72623-2 | |
| Order Code | 503870 | |||||
| Order Code Name | Infliximab Drug + Antibody | |||||
| Order Loinc | ||||||
| Result Code | 503772 | |||||
| Result Code Name | Infliximab Drug Level | |||||
| UofM | ug/mL | |||||
| Result LOINC | 39803-2 | |||||
| Order Code | 503870 | |||||
| Order Code Name | Infliximab Drug + Antibody | |||||
| Order Loinc | ||||||
| Result Code | 503773 | |||||
| Result Code Name | Anti-Infliximab Antibody | |||||
| UofM | ng/mL | |||||
| Result LOINC | 72623-2 |
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 504107 | Serial Monitoring | 000000 | Serial Monitoring | N/A | |
| Reflex 1 | ||||||
| Order Code | 504107 | |||||
| Order Name | Serial Monitoring | |||||
| Result Code | 000000 | |||||
| Result Name | Serial Monitoring | |||||
| UofM | ||||||
| Result LOINC | N/A | |||||
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 504107 | Serial Monitoring | 511958 | 80563-0 | ||
| Reflex 1 | ||||||
| Order Code | 504107 | |||||
| Order Name | Serial Monitoring | |||||
| Result Code | 511958 | |||||
| Result Name | ||||||
| UofM | ||||||
| Result LOINC | 80563-0 | |||||