• The detection of autoantibodies (antibodies against "self" cells and tissues) helps confirm the diagnoses of various autoimmune conditions.
• Some of the most commonly tested autoantibodies are listed in the chart below. Among those, rheumatic factor (RF) and antinuclear antibody (ANA) are the two most common tests used as first screen for autoimmune disorders.
• Additional tests such as complete blood count, liver function tests, urinalysis, and synovial fluid analysis are often indicated in the assessment of organ involvement of rheumatologic diseases.
rf - ana
• Rheumatoid factor (RF) and antinuclear antibody (ANA) are the two most routinely tested antibodies in the workup of rheumatologic and other autoimmune disorders.
• However, RF and ANA are non-specific thus are often used as first screening tests.
• Conditions associated with elevated RF and ANA include rheumatologic diseases, vasculitis, along with a number of organ-specific autoimmune disorders, chronic inflammation, infection, and malignancy.
POSITIVE RHEUMATIC FACTOR (RF)
✿ Connective tissue disorders
✧ rheumatoid arthritis
✧ sjogren syndrome
✧ mixed connective tissue disorder
✧ systemic lupus erythematosus
✧ polymyositis/dermatomyositis
✿ Systemic vasculitis
✧ polyarteritis nodosa
✧ anca-associated vasculitis
☼ wegener granulomatosis
☼ churg-strauss syndrome
☼ microscopic polyangiitis
✧ mixed cryoglobulinemia
✿ Other autoimmune disorders
✧ sarcoidosis
✧ primary biliary cirrhosis
✧ idiopathic pulmonary fibrosis
✿ Chronic inflammation
✧ malignancy (b-cell neoplasms)
✧ silicosis
✧ asbestosis
✿ Chronic infection
✧ subacute bacterial endocarditis
✧ bacterial (tb, leprosy, syphillis)
✧ viral (hbv, hcv)
✧ parasitic
POSITIVE ANTINUCLEAR ANTIBODIES (ANA)
✿ Connective tissue disorders
✧ systemic lupus erythematosus
✧ discoid lupus erythematosus
✧ drug-induced lupus erythematosus
✧ mixed connective tissue disorder
✧ scleroderma
✧ sjogren syndrome
✧ rheumatoid arthritis
✧ polymyositis/dermatomyositis
✿ Other autoimmune disorders
✧ drug-induced ana
✧ autoimmune hepatitis
✧ primary biliary cirrhosis
✧ autoimmune cholangitis
✧ inflammatory bowel disease
✧ hashimoto thyroiditis
✧ graves' disease
✧ idiopathic pulmonary fibrosis
✿ Chronic infection
✧ subacute bacterial endocarditis
✧ bacterial (tb, syphillis)
✧ viral (hiv, hcv, ebv)
✿ Malignancy
✧ lymphoproliferative disorders
✧ paraneoplastic syndromes
common autoantibodies
