#ExistRefRange>29 AU/mL or less: Negative
30-40 AU/mL: Equivocal
41 AU/mL or greater: Positive
#ExistInterpData>RNP antibody is seen in 95-100% of mixed connective tissue disease and is considered specific for this syndrome if other antibodies are negative; RNP is also present in 20-30% of systemic lupus erythematosus and 15-25% of progressive systemic sclerosis.
||RNP antigens also contain epitopes which are immunologically identical to free Smith antigens. The Smith antibody response must be considered when interpreting RNP results.
||Anti-RNP (ENA) Antibody (RNP (U1) (Ribonucleic Protein) (ENA) Antibody, IgG), Sm/RNP Antibody (RNP (U1) (Ribonucleic Protein) (ENA) Antibody, IgG), U1 RNP (RNP (U1) (Ribonucleic Protein) (ENA) Antibody, IgG)