[Rhupus: when rheumatoid arthritis meets lupus]

Area of Science:

• Rheumatology
• Immunology
• Internal Medicine

Context:

• Distinguishing between overlapping autoimmune diseases like rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) can be challenging.
• The term "rhupus" describes patients who fulfill classification criteria for both RA and SLE.
• Identifying specific autoantibodies aids in diagnosing and classifying these complex conditions.

Purpose:

• To identify and characterize patients with overlapping features of RA and SLE (rhupus) using a retrospective database analysis.
• To investigate the presence of anti-cyclic citrullinated peptide (CCP) antibodies (RA marker) and anti-double-stranded DNA (anti-dsDNA) antibodies (SLE marker) in patients with overlapping symptoms.

Summary:

• A retrospective analysis of the GLIMS database identified 16 patients with features of both RA and SLE.
• Six patients were classified as potential rhupus cases, all being women with a median age of 51, and positive for anti-SS-A antibodies.
• Nine patients were diagnosed with RA exhibiting anti-dsDNA antibodies, likely induced by anti-TNF-alpha therapies.

Impact:

• This study aids in the classification and understanding of rhupus, a challenging autoimmune condition.
• The findings highlight the importance of specific autoantibody profiles in differentiating overlapping rheumatological diseases.
• Characterizing rhupus patients can inform targeted treatment strategies and improve patient outcomes in complex autoimmune cases.