Striated Muscle Antibodies, IgG with Reflex to Titer
0050746
Ordering Recommendation
Secondary-line test for the evaluation of myasthenia gravis. Recommended if first-line diagnostic tests are negative.
Mnemonic
STM R
Methodology
Semi-Quantitative Indirect Fluorescent Antibody
Performed
Mon-Fri
Reported
1-5 days  
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
Specimen Required
Patient Preparation
  
Collect
Serum separator tube.  
Specimen Preparation
Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.15 mL)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
Plasma. Contaminated, hemolyzed, or severely lipemic specimens.  
Remarks
  
Stability
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)  
Reference Interval
Screen:  < 1:40 No antibodies detected.
Titer:    < 1:40 No antibodies detected.  
Interpretive Data
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 myasthenia gravis (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, rheumatic fever, myocardial infarction, and following some cardiotomy procedures.  
Note
If Striated Muscle Abs is greater than 1:40, then a titer will be added.  Additional charges may apply.
CPT Code(s)
86255; if reflexed, add 86256
Components
Component Test Code*Component Chart NameLOINC
0050747Striated Muscle Antibodies, IgG Screen49692-7
0050748Striated Muscle Antibodies, IgG Titer29998-2
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • Anti-Skeletal Muscle IgG Antibodies
  • Anti-Striated Antibody
  • Anti-Striated Muscle Antibody
  • Muscle (Skeletal) Antibodies
  • Myoid Antibody
  • Skeletal Muscle Antibodies
  • Striational Antibodies