Comprehensive Laboratory Tests for Autoimmune Disease Workup
A comprehensive autoimmune workup should include inflammatory markers, complete blood count, autoantibody panels, and organ-specific tests based on clinical presentation to accurately diagnose and monitor autoimmune conditions.
Initial Laboratory Evaluation
- Complete blood count (CBC) with differential to assess for cytopenias, which are common in many autoimmune conditions 1
- Inflammatory markers including erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) to evaluate disease activity 1, 2
- Comprehensive metabolic panel including liver and kidney function tests to assess for organ involvement 1
- Antinuclear antibody (ANA) testing as a screening tool for many systemic autoimmune diseases 1
- Rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies for suspected inflammatory arthritis 3, 1
Disease-Specific Autoantibody Testing
- For suspected systemic lupus erythematosus: anti-dsDNA, anti-Smith, anti-RNP, anti-SSA, anti-SSB antibodies 1
- For suspected systemic sclerosis: anti-centromere, anti-Scl-70, anti-RNA polymerase III antibodies 1
- For suspected autoimmune hepatitis: anti-smooth muscle antibodies, anti-liver kidney microsomal antibodies, and serum immunoglobulins 3
- For suspected myositis: anti-Jo-1 and other myositis-specific antibodies 3
- For suspected vasculitis: anti-neutrophil cytoplasmic antibodies (ANCA) with proteinase-3 and myeloperoxidase specificity 4
Organ-Specific Testing
Musculoskeletal System
- Creatine kinase (CK), transaminases (AST, ALT), lactate dehydrogenase (LDH), and aldolase for suspected inflammatory myopathies 3
- Troponin to evaluate for cardiac involvement in inflammatory myositis 3
Gastrointestinal System
- Liver function tests and hepatitis serologies to exclude viral causes of liver disease 3
- Consider testing for celiac disease antibodies (tissue transglutaminase, endomysial antibodies) in appropriate clinical settings 1
Endocrine System
- Thyroid function tests (TSH, free T4) and thyroid antibodies (anti-TPO, anti-thyroglobulin) for suspected autoimmune thyroid disease 3
Neurological System
- Cerebrospinal fluid analysis including cell count, protein, glucose, IgG index, and oligoclonal bands for suspected autoimmune neurological conditions 3
- Neural-specific antibodies for suspected autoimmune encephalitis 3
Additional Testing Based on Clinical Presentation
- HLA typing (particularly HLA-B27) for suspected spondyloarthropathies 3
- Complement levels (C3, C4, CH50) for suspected lupus or complement deficiencies 1
- Cryoglobulins and serum protein electrophoresis for suspected cryoglobulinemic vasculitis 3
- Iron studies including ferritin and transferrin saturation to exclude hemochromatosis in patients with elevated liver enzymes 3
Monitoring Disease Activity
- Serial measurements of inflammatory markers (ESR, CRP) to assess treatment response 1, 2
- Disease-specific autoantibody titers may be useful for monitoring certain conditions 2
- Cytokine profiling (IL-6, IL-10, IL-17A) may provide additional information about disease activity and treatment response 2
Common Pitfalls to Avoid
- Relying solely on autoantibody testing without clinical correlation can lead to misdiagnosis 1
- Not screening for infectious diseases (HIV, hepatitis, tuberculosis) before starting immunosuppressive therapy 1
- Failing to consider drug-induced autoimmunity as a potential cause of symptoms 1
- Not testing for multiple autoimmune conditions, as they frequently coexist 1
Special Considerations
- Autoantibody testing should be performed before initiating immunosuppressive therapy when possible, as treatment may affect results 3
- Consider testing for latent tuberculosis and viral hepatitis before starting immunosuppressive therapy 1
- In patients with suspected autoinflammatory syndromes, genetic testing may be warranted 3