Anti-cN-1A (NT5c1A) IBM
Test Mnemonic
CN1AAB
CPT Codes
- 83516 - QTY (1)
Aliases
- Anti-IBM
- IBM
- Inclusion Body Myopathy
- MUP44 AB
- nt5c1a
- sIBM
- sporadic IBM
Includes
- Anti-cN-1A (NT5c1A) IBM
Performing Laboratory
LabCorp
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2 mL | Serum | No additive (Red) | Refrigerated | Separate serum from cells ASAP or within 1 hour of collection and transfer to standard aliquot tube. Additional specimens must be submitted when multiple tests are ordered. |
Alternate Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 2 mL | Serum | SST (Gold) | Refrigerated | Separate serum from cells ASAP or within 1 hour of collection and transfer to standard aliquot tube. Additional specimens must be submitted when multiple tests are ordered. |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 0.5 mL | Does not allow for repeat testing |
Stability
| Environmental Condition | Description |
|---|---|
| Refrigerated | 14 days |
| Frozen | 60 days (1 freeze/thaw cycle) |
| Ambient | 7 days |
Days Performed
Varies
Turnaround Time
8 - 11 days
Methodology
| Name | Description |
|---|---|
| Enzyme-Linked Immunosorbent Assay (ELISA) |
Reference Range
| Anti-cN-1A (NT5c1A) IBM | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| Negative: <20 | Weak Positive: 20 - 39 | Moderate Positive: 40 - 80 | Strong Positive: >80 |
Special Info
Grossly hemolyzed, lipemic or icteric specimens will be rejected.
Clinical Info
Anti-cN-1A autoantibodies in idiopathic inflammatory myopathy (IIM) patients appear to be disease-specific for sporadic Inclusion Body Myositis (sIBM) and are rarely detected in other autoimmune conditions. Anti-cN-1A autoantibodies have a moderate sensitivity, but their high specificity for sIBM may be helpful in the diagnosis of this infrequent and difficult-to-diagnose myopathy. This assay can augment and accelerate the suspected diagnosis of sIBM using sera where muscle biopsy is delayed and/or unfeasible.