Skeletal Muscle Antibodies IgG with Reflex to Titer
Test Mnemonic
SKELS
CPT Codes
- 86255 - QTY (1)
Aliases
- Striational Muscle Total Abs
Performing Laboratory
ARUP
Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 1 mL | Serum | SST (Gold) | Refrigerated | Separate serum from cells ASAP or within 2 hours of collection and transfer into standard aliquot tube. |
Minimum Specimen Requirements
| Volume | Type | Container | Collect Temperature | Transport Temperature | Special Instructions |
|---|---|---|---|---|---|
| 0.15 mL |
Stability
| Environmental Condition | Description |
|---|---|
| Ambient | After separation from cells: 48 hours |
| Refrigerated | After separation from cells: 2 weeks |
| Frozen | After separation from cells: 1 year (Avoid repeated freeze/thaw cycles) |
Days Performed
Mon - Fri
Turnaround Time
2 - 6 days
Methodology
| Name | Description |
|---|---|
| Semi-Quantitative Indirect Fluorescent Antibody |
Reference Range
| Striated Muscle Antibody, IgG Screen | |||||
|---|---|---|---|---|---|
| Sex | Age From | Age To | Type | Range | Range Unit |
| Years | 99 Years | Normal | < 1:40 No antibody detected | . |
Special Info
If skeletal muscle antibodies are detected, a titer will be added at an additional cost. Plasma, contaminated, hemolyzed, or severely lipemic specimens are unacceptable. This test is New York DOH approved.
Clinical Info
This test is recommended for the differential evaluation of neuromuscular junction diseases including myasthenia gravis (MG). When detected in the presence of acetylcholine receptor (AChR) antibody, striated muscle antibodies, which bind in a cross-striational pattern to skeletal and heart muscle tissue sections, are associated with late-onset MG. Striated muscle antibodies recognize epitopes on three major muscle proteins, including titin, ryanodine receptor (RyR) and Kv1.4 (an alpha subunit of voltage-gated potassium channel [VGKC]). Isolated cases of striated muscle antibodies may be seen in patients with certain autoimmune diseases, myocardial infarction, rheumatic fever, and following some cardiotomy procedures.