Test Center

My Recent Searches

  • No Recent Search.

My Tests Viewed

  • No Test Viewed.

Rheumatic and Related Diseases: Laboratory Support of Diagnosis

Rheumatic and Related Diseases: Laboratory Support of Diagnosis

Test Guide

Rheumatic and Related Diseases

Laboratory Support of Diagnosis

  

Rheumatic diseases comprise a group of autoimmune disorders that include rheumatoid arthritis, polymyositis, Sjögren’s syndrome, systemic lupus erythematosus (SLE), systemic sclerosis, and others. The laboratory work-up for patients with suspected rheumatic disease often begins with an antinuclear antibody (ANA) screen. The classic ANA testing approach uses HEp-2 human tissue culture cells in an immunofluorescence assay (IFA) to detect autoantibodies directed against antigens in the cell cytoplasm and nucleus. Because it is highly sensitive, this method is considered by the American College of Rheumatology to be the current gold standard.1

The IFA is highly sensitive because it detects a large number of antigens; however, these antigens are not very disease specific. Multiplex immunoassays such as ANAchoice® identify commonly occurring autoantibodies strongly associated with particular rheumatic diseases; these assays may be more specific than IFA for these diseases.2 Although such assays can identify multiple autoantibodies simultaneously, the number of antibodies detected is less than in the IFA, hence the lower screening sensitivity. Thus, the IFA and immunoassay methods complement each other for the initial evaluation of suspected rheumatic disorders (Table 1). When ANA is positive by IFA, especially with high titer, testing for disease-specific antibodies such as those included in the ANAchoice test can help with the differential diagnosis3-5 (Figure).

Samples with an IFA titer <1:40 are considered negative for ANA antibodies; follow-up with more specific testing is not needed. Higher titers are generally associated with greater likelihood of rheumatic disease, but do not reflect disease activity. When results are positive, various fluorescent staining patterns are observed in the nucleus or the cytoplasm (Table 2). These patterns can aid in the differential diagnosis of a rheumatic disease. Similarly with ANAchoice, the pattern of positive and negative antibody results may point to a particular rheumatic disease. When a particular rheumatic disorder is initially suspected, test selection can be targeted to help with the diagnosis of that disorder (Table 3).

Table 1. First-Line Tests for Diagnosis of Rheumatic and Related Diseases

Test Code

249a

16814a,b

19946(X)a,b

Test Name ANA Screen, IFA with Reflex to Titer and Pattern, IFA
 
ANA Screen (IFA) with Reflex to Titer/Pattern/ANAchoice® Cascade

ANAchoice® Specific Antibodies Cascading Reflex

Method(s) Immunofluorescence (IFA) using HEp-2 cells IFA and multiplex flow immunoassay Multiplex flow immunoassay

Analytical

Sensitivity,

Specificity

High sensitivity: can detect antibodies for up to 150 antigens; not autoantibody specific Both sensitive and autoantibody specific Specific for the 11 more commonly occurring autoantibodies; less sensitive

Results

Reported

IFA screen positive or negative IFA screen positive or negative ANAchoice screen positive or negative

Reflex Testing

If screen positive, IFA titer and pattern
 
If screen positive, IFA titer
and pattern, plus dsDNA,
Sm, Sm/RNP, RNP, and chromatin antibodies index/interpretation

If screen positive and all above antibodies negative, SS-A, SS-B, Scl-70, and
Jo-1 antibodies index/ interpretation

If screen positive and all above antibodies negative, centromere B and
ribosomal P antibodies index/interpretation

If screen positive, dsDNA, Sm, Sm/RNP, RNP, and chromatin antibodies index/interpretation

If screen positive and all above antibodies negative, SS-A, SS-B, Scl-70, and
Jo-1 antibodies index/interpretation

If screen positive and all above antibodies negative, centromere B and
ribosomal P antibodies index/interpretation

Result Interpretation

Negative screen: rheumatic disease highly unlikely

Positive screen: rheumatic disease not ruled in; 20%
to 30% of healthy patients have a positive result at a titer of 1:40.3

Negative screen: rheumatic disease highly unlikely

Positive screen, negative ANAchoice cascade: rheumatic disease not
ruled in or out

Negative ANAchoice: rheumatic disease not ruled out; consider other autoantibodies if clinically indicated

Positive ANAchoice: rheumatic disease highly likely

ANA, antinuclear antibody; IFA, immunofluorescent assay; dsDNA, double-stranded DNA; Sm/RNP antibody, Smith/ribonucleoprotein antibody; SS-A, SS-B antibodies, Sjögren’s syndrome A and B antibodies; Scl-70 antibody, scleroderma (topoisomerase 1) antibody; and Jo-1 antibody, histidyl-tRNA synthetase antibody.
a Reflex tests are performed at an additional charge and are associated with an additional CPT code(s).
b The antibodies listed can be ordered separately; refer to the Quest Diagnostics Directory of Services for ordering details.

Figure. Antibody Testing Cascade for Screening and Diagnosis of Patients with Suspected Rheumatic Disease
Table 2. Interpretation of Nuclear and Cytoplasmic Antinuclear Antibody (IFA) Patterns
Antibody Pattern Interpretation
Nuclear Patterns

Nuclear membrane (nuclear laminae, rim)
 

Associated with autoimmune liver disease including primary biliary cirrhosis and autoimmune hepatitis

Centromere
 

Associated with the CREST syndromea or Raynaud syndrome

Homogenous
 

Consistent with presence of antibodies to native DNA, histones, and/or deoxyribonucleoprotein

Nucleolar
 

Suggestive of scleroderma, SLE, Sjögren’s syndrome, polymyositis, overlap syndromes, or Raynaud phenomenon

Proliferating cell nuclear antigen (PCNA)

Highly specific for SLE

Speckled

Suggestive of antibodies to RNP, SS-A, SS-B, Sm, centromere, p95 or p80 coilin

Cytoplasmic Patterns

Cytoskeletal
 

Associated with autoimmune liver disease (anti-smooth muscle); myasthenia gravis, Crohn disease, and long-term hemodialysis; alcoholic liver disease, rheumatoid arthritis, and psoriasis (anti-keratin)

Golgi apparatus
 

Consistent with SLE, Sjögren’s syndrome, cerebellar disease, and viral infections

Lysosomal

Unknown clinical significance

Mitochondrial
 

Suggestive of antimitochondrial antibody presence and primary biliary cirrhosis

Ribosomal

Unknown clinical significance; may be associated with neuropsychiatric lupus
SLE, systemic lupus erythematosus; RNP antibody, ribonucleoprotein antibody; SS-A, SS-B antibodies, Sjögren’s antibodies A and B; and Sm antibody, Smith antibody.
a CREST is a syndrome defined by presence of calcinosis, Raynaud’s phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia.
  
Table 3. Rheumatic Disease-targeted Diagnostic Testing Available from Quest Diagnosticsa,b
Test Code Test Name
10547(X) ANAchoice® Specific Antibodies with Reflex to dsDNA
90071 ANA (IFA) Rheumatoid Arthritis Diagnostic Panel with Reflex Titer, Pattern
Includes interpretation, ANA screen (IFA) with reflex to titer and pattern, rheumatoid factor, and cyclic citrullinated peptide (CCP) IgG.
90072 ANA, IFA with Reflex to Titer/Pattern/Lupus/SLE Antibodies
Includes interpretation; ANA screen (IFA) with reflex to titer and pattern and dsDNA, Sm, and chromatin antibodies.
90074 ANA, IFA with Reflex to Titer/Pattern/Mixed Connective Tissue Disease Antibodies
Includes interpretation; ANA screen (IFA) with reflex to titer and pattern and RNP, Scl-70, and dsDNA antibodies.
90073 ANA, IFA with Reflex to Titer/Pattern/Scleroderma Antibodies
Includes interpretation; ANA screen (IFA) with reflex to titer and pattern and Scl-70 and centromere B antibodies.
90077 ANA, IFA Sjögren Panel with Reflex to ANA Titer and Pattern
Includes interpretation, ANA screen (IFA) with reflex to titer and pattern, Sjögren’s antibodies (SS-A and SS-B), and rheumatoid factor IgM.
19875(X) Mixed Connective Tissue Disease Syndrome Panel
Includes ANA screen with reflex to titer and pattern and RNP antibody.
7809(X) Polymyositis/Dermatomyositis Antibody Panel
Includes Jo-1 and PM-Scl antibodies.
17669(X) Rheumatoid Arthritis Diagnostic Panel
Includes rheumatoid factor IgM and CCP IgG.
19878(X) Rheumatoid Arthritis Diagnostic Panel, Comprehensive
Includes rheumatoid factor IgG, IgA, and IgM; CCP IgG; and SS-A and SS-B antibodies.
91472 Rheumatoid Arthritis Diagnostic Panel with 14-3-3 eta Proteinc
Includes rheumatoid factor IgM, CCP IgG, and 14-3-3 eta protein.
19880(X) Sjögren’s Syndrome Diagnostic Panel, Comprehensive
Includes ANA screen (IFA) with reflex to titer and pattern, rheumatoid factor, SS-A and SS-B antibodies, mitochondrial antibody screen with reflex to titer, and thyroid peroxidase (TPO) antibody.
19881(X) Systemic Lupus Erythematosus (SLE) Comprehensive Diagnostic Panel
Includes ANA screen (IFA) with reflex to titer and pattern; complement component C4c and C3c; total complement (CH50); and dsDNA, chromatin (nucleosomal), RNP, Sm, and SS-A and SS-B antibodies.
19874(X) Systemic Lupus Erythematosus (SLE) Diagnostic Panel, Drug Induced
Includes ANA screen (IFA) with reflex to titer and pattern and histone antibody.

ANA, antinuclear antibody; IFA, immunofluorescent assay; SLE, systemic lupus erythematosus; dsDNA, double-stranded DNA; Sm antibody, Smith antibody; RNP antibody, ribonucleoprotein antibody; Scl-70 antibody, scleroderma (topoisomerase I) antibody; Jo-1 antibody, histidyl-tRNA synthetase antibody; PM-Scl antibody, polymyositis-scleroderma antibody.
a All tests listed in panels can be ordered separately.
b Reflex tests are performed at an additional charge and are associated with an additional CPT code(s).
c This test was developed and its performance characteristics have been determined by Quest Diagnostics Nichols Institute. It has not been cleared or approved by the U.S. Food and Drug Administration. The FDA has determined that such clearance or approval is not necessary. Performance characteristics refer to the analytical performance of the test.

References

  1. Krapf AR, von Muhlen CR, Krapf EE, Nakamura RN, Tan EM, eds. Atlas of Immunofluorescent Autoantibodies. Baltimore, MD: Urban and Schwarzenberg; 1996.

  2. American College of Rheumatology Position Statement. Methodology of testing for antinuclear antibodies. Available at: www.rheumatology.org/practice/ana_position_stmt.pdf. Approved February 2009. Accessed February 7, 2013.

  3. Gniewek RA, Stites DP, McHugh TM, et al. Comparison of antinuclear antibody testing methods: immunofluorescence assay versus enzyme immunoassay. Clin Diagn Lab Immunol. 1997;4:185-188.

  4. Kavanaugh A, Tomar R, Reveille J, et al. Guidelines for clinical use of the antinuclear antibody test and tests for specific autoantibodies to nuclear antigens. Arch Pathol Lab Med. 2000;124:71-81.

  5. Satoh M, Chan EKL, Sobel ES, et al. Clinical implication of autoantibodies in patients with systemic rheumatic diseases. Expert Rev Clin Immunol. 2007;3:721-738.

  6. Stinton LM, Fritzler MJ. A clinical approach to autoantibody testing in systemic autoimmune rheumatic disorders.Autoimmun Rev. 2007;7:77-84.

  7. Petri M, Orbai AM, Alarcόn GS, et al. Derivation and validation of systemic lupus international collaborating clinics classification criteria for systemic lupus erythematosus. Arthritis Rheum. 2012;64:2677-2686.

  8. Cappelli S, Randone SB. “To be or not to be,” ten years after: evidence for mixed connective tissue disease as a distinct entity. Semin Arthritis Rheum. 2012;41:589-598.

Content reviewed 04/2013
top of page

* The tests listed by specialist are a select group of tests offered. For a complete list of Quest Diagnostics tests, please refer to our Directory of Services.