CRP and autoimmune disease: We discarded the presence of associated autoimmune diseases in patients due to all the immunological testing included, as tests for C-reactive protein, rheumatoid factor, antinuclear antibodies, anti-DNA antibodies, antiribonucleoprotein antibodies, anti-Ro antibodies, anti-Sm antibodies, anti-Jo-1 antibodies and antineutrophil cytoplasmic antibodies were negative.