RNP Ab in serum

Etiology

• systemic lupus erythematosus (46%)
• scleroderma
• rheumatoid arthritis
• discoid lupus
• Sjogren's syndrome
• mixed connective tissue disease (high titer)

Reference interval

• Normal: negative for antibodies to RNP [<20 EU/mL]

Clinical significance

Antibodies to Smith antigen (anti-Sm Ab) & to U1 RNP (anti-U1 RNP Ab) are associated with antibodies to small nuclear RNP associated with the spliceosome.

Interpretation

• < 20 EU/mL: negative for antibodies to RNP
• 20-25 EU/mL: equivocal for antibodies to RNP
• >25 EU/mL: positive for antibodies to RNP

More general terms

• RNP Ab in body fluid

More specific terms

• fibrillarin (U3 RNP) Ab in serum
• RNP 52kD Ab in serum
• RNP 63kD Ab in serum
• RNP IgG in serum
• Sm (Smith) Ab in serum
• SM+RNP Ab in serum
• U1 RNP Ab in serum
• U2 RNP Ab in serum

Additional terms

• ribonucleoprotein

Component of

• Smith antigen (Sm) & ibonucleoprotein (RNP) Ab in serum
• extractable nuclear antigen (ENA) Ab