Here is a list of some common antibodies associated with rheumatologic diseases:

Systemic Lupus Erythematosus (SLE)

• Antinuclear Antibodies (ANA): The most common screening test; positive in most SLE patients.
• Anti-dsDNA (anti-double-stranded DNA): Highly specific for SLE, associated with lupus nephritis.
• Anti-Sm (Smith Antibody): Highly specific for SLE, though less common than anti-dsDNA.
• Anti-Ro/SSA and Anti-La/SSB: Associated with neonatal lupus, Sjögren’s syndrome, and photosensitive skin rashes in SLE.
• Antiphospholipid Antibodies (aPL): Including anticardiolipin antibodies, lupus anticoagulant, and anti-beta-2 glycoprotein I; linked to antiphospholipid syndrome in SLE.

Rheumatoid Arthritis (RA)

• Rheumatoid Factor (RF): Present in about 70-80% of RA patients.
• Anti-Cyclic Citrullinated Peptide (Anti-CCP): Highly specific for RA, predictive of erosive disease.

Sjögren’s Syndrome

• Anti-Ro/SSA and Anti-La/SSB: Found in a majority of primary Sjögren’s patients, also overlap with SLE.

Systemic Sclerosis (Scleroderma)

• Anti-Scl-70 (anti-topoisomerase I): Associated with diffuse cutaneous systemic sclerosis.
• Anti-centromere antibodies: More specific for limited cutaneous systemic sclerosis (CREST syndrome).
• Anti-RNA Polymerase III: Linked to rapidly progressive skin changes and increased risk of renal crisis.

Polymyositis/Dermatomyositis

• Anti-Jo-1 (anti-histidyl-tRNA synthetase): Associated with interstitial lung disease and arthritis in myositis.
• Anti-Mi-2: Found in some patients with dermatomyositis, associated with better prognosis regarding muscle disease.

Mixed Connective Tissue Disease (MCTD)

• Anti-U1-RNP (anti-ribonucleoprotein): High titers are characteristic of MCTD.

Vasculitis

• Anti-Neutrophil Cytoplasmic Antibodies (ANCA):
  • c-ANCA (PR3-ANCA): Associated with granulomatosis with polyangiitis (Wegener’s).
  • p-ANCA (MPO-ANCA): Seen in microscopic polyangiitis and Churg-Strauss syndrome (eosinophilic granulomatosis with polyangiitis).

Spondyloarthropathies

• HLA-B27: Not an antibody but a genetic marker associated with ankylosing spondylitis, reactive arthritis, and psoriatic arthritis.

Other Notable Antibodies:

• Anti-RNP (Ribonucleoprotein): Can be seen in various autoimmune conditions, including MCTD.
• Anti-SS-A/Ro and Anti-SS-B/La: As mentioned, not exclusive to one disease; also seen in subacute cutaneous lupus erythematosus.

Considerations:

• The presence of an antibody does not always mean the disease is present, and absence doesn’t rule it out; clinical correlation is crucial.
• Some antibodies can be found in healthy individuals or with other autoimmune conditions (overlap syndromes).
• Diagnosis of rheumatologic diseases often requires a combination of clinical findings, imaging, and other laboratory tests in addition to antibody testing.

When interpreting these results, it’s vital to work with a rheumatologist or healthcare provider who can synthesize all clinical data to reach an accurate diagnosis.