title: Negative anti-C1q antibody titers may influence therapeutic decisions and reduce the number of renal biopsies in systemic lupus erythematosus.
abstract: In a cross-sectional study involving 62 patients with systemic lupus erythematosus (SLE), we found that patients with biopsy-proven lupus nephritis (LN) had higher titers of anti-C1q antibodies than active SLE without nephritis patients. Anti-C1q was associated with a negative predictive value of 94.59%, a positive predictive value of 52%, a sensitivity of 86.66% and a specificity of 74.47% for the diagnosis of LN. We conclude that high titers of anti-C1q antibodies are strongly associated with the presence of active LN, and the negative predictive value of this test for diagnosing LN is very high; therefore, it can influence therapeutic decisions and reduce the number of renal biopsies in patients with SLE.
authors.affiliation: Bahiana School of Medicine and Public Health, São Paulo, Brazil.
authors.forename: Carlos Geraldo Guerreiro de
authors.initials: CG
authors.lastname: Moura
authors.forename: Cristóvão Luis Pitangueira
authors.initials: CL
authors.lastname: Mangueira
authors.forename: Luzia Arlinda Sampaio
authors.initials: LA
authors.lastname: Cruz
authors.forename: Constança Margarida Sampaio
authors.initials: CM
authors.lastname: Cruz
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000096:biosynthesis / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001707:Biopsy, Needle; D015922:Complement C1q / Q000276:immunology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007668:Kidney / Q000473:pathology; D008180:Lupus Erythematosus, Systemic / Q000097:blood* / Q000473:pathology / Q000628:therapy*; D008181:Lupus Nephritis / Q000097:blood* / Q000175:diagnosis*; D008297:Male; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D015922:Complement C1q