Rheumatoid Factor Positive

# Rheumatoid Factor Positive
RF is a nonspecific biomarker, with ~10% of population >65 y.o being RF+. Other than true rheumatoid arthritis as a cause of RF+, common etiologies include infection (Hep C, osteomyelitis, SBE, HIV, Syphilis), Cryoglobulinemia (~100%), autoimmune/inflammatory (Sjogrens (20-30%), SLE (15-25%), Scleroderma (10-20%), Polymyositis/Dermatomyositis (5-10%), sarcoidosis), IPF and cirrhosis.
- CCP if concerned for RA, additiona dx per clinical scenario