Myositis Specific 11 Ab Panel

Test Code

71334

CPT Codes
PROF

Includes

Jo-1 Ab, PL-7 Ab, PL-12 Ab, EJ Ab, OJ Ab, SRP Ab, Mi-2 Alpha Ab, Mi-2 Alpha Ab, Mi-2 Beta Ab, MDA-5 Ab, TIF-1y Ab, NXP-2 Ab

Preferred Specimen

0.5 mL (0.3 mL minimum) serum

Transport Container: Plastic leak-proof container
Transport temperature: Room temperature

Minimum Volume

0.3 mL

Specimen Stability

Room temperature: 7 days
Refrigerated: 14 days
Frozen: 28 days

Methodology
Line Blot

Setup Schedule

Set up: Tues-Sat; Report available: 4 days

Report Available

4 days

Reference Range

Jo-1 Ab	<11 SI
PL-7 Ab	<11 SI
PL-12 Ab	<11 SI
EJ Ab	<11 SI
OJ Ab	<11 SI
SRP Ab	<11 SI
Mi-2 Alpha Ab	<11 SI
Mi-2 Beta Ab	<11 SI
MDA-5 Ab	<11 SI
TIF-1y Ab	<11 SI
NXP-2 Ab	<11 SI

Clinical Significance

Myositis-specific autoantibodies (MSAs) are highly selective, usually exclusive and are associated with particular clinical phenotypes within the myositis spectrum. Myositis-specific autoantibodies to cytoplasmic enzymes that catalyze the binding of specific amino acids to their cognate tRNA define the anti-synthetase syndrome characterized by myositis and lung inflammation, and include autoantibodies to Jo-1 (antihistidyl-tRNA synthetase), PL-7 (threonyl), PL-12 (alanyl), EJ (glycyl), and OJ (isoleucyl). A further subset of myositis patients is characterized by the presence of autoantibodies directed against the signal recognition particle (SRP). Autoantibodies to Mi-2 (Mi-2/nucleosome remodelling and deacetylase (NuRD) complex) are detected in patients with hallmark dermatomyositis features. Autoantibody to a cytoplasmic 140-kDa protein, melanoma-differentiation associated gene 5 (MDA5), also known as anti-CADM140, identified patients with clinically amyopathic dermatomyositis (CADM) and rapidly progressive lung disease. Autoantibodies to transcriptional intermediary factor 1-gamma (TIF-1 y), a p155/140 nuclear protein involved in cellular differentiation, have been reported in adult and juvenile dermatomyositis; in adults, it is associated with malignancy. Autoantibodies to nuclear matrix protein NXP-2, another 140-kDa protein, is found in juvenile dermatomyositis (JDM). Anti-TIF-1 y and anti-NXP-2, two novel serological subsets in JDM, occur collectively in >40% of children and appear to identify those with more severe disease.

Performing Laboratory
Quest Diagnostics Nichols SJC

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.