Caspian Journal of Internal Medicine

fa Serum alpha–actinin antibody status in systemic lupus erythematosus and its potential in the diagnosis of lupus nephritis Internal Internal Original Article Original Article Background: In lupus nephritis (LN), deposition of pathogenic autoantibodies in the glomeruli is mediated via cross-reactivity with alpha-actinin. Association of serum alpha-actinin antibody (AαA) with LN has been shown in a few studies but the results are controversial. Methods: Eighty patients into entered the study. The diagnosis of SLE was confirmed according to the American College of Rheumatology criteria and LN was diagnosed by proteinuria ≥ 500 mg/24 hour and kidney biopsy. Serum AαA was measured with ELISA method. Receiver operating characteristics curve (ROC) analysis was applied to determine an optimal cutoff value for AαA to discriminate patients with and without LN at the highest sensitivity and specificity. The association of AαA with LN was determined by logistic regression analysis with calculation of odds ratio (OR). Results: Serum AαA was significantly lower in LN as compared with SLE patients without LN (P=0.001). Serum AαA at cutoff levels ≤ 59.5 pg/ml discriminated the two groups with sensitivity, specificity, positive predictive values of 60%. 90% and 85.7%, respectively. Serum AαA level ≤ 59.5 pg/ml was significantly associated with LN (OR=13.5, P=0.001) and the OR increased to 25.2 (P=0.003) after adjustment for age, sex, C3, C4, anti-ds-DNA, SLEDAI. Conclusion: This study indicates that serum AαA decreases in LN and serum level ≤ 59.5 pg/ml is SLE and is predictive of nephritis. Systemic lupus erythematous, Nephritis, Anti-alpha-actinicn antibody, Diagnosis 272 277 http://caspjim.com/browse.php?a_code=A-10-564-1&slc_lang=fa&sid=1 Mansour Babaei babaeim47@yahoo.com 10031947532846006626 10031947532846006626 No Department of Rheumatology, Ayatollah Rouhani Hospital, Babol University of Medical Sciences, Babol, Iran Zahra Rezaieyazdi rezaieyazdi-z@mums.ac.ir. 10031947532846006627 10031947532846006627 No Rheumatic Disease Research Center,School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Nayereh Saadati Saadatin@mums.ac.ir 10031947532846006628 10031947532846006628 Yes Rheumatic Disease Research Center,School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Massoud Saghafi saghafim@mums.ac.ir 10031947532846006629 10031947532846006629 No Rheumatic Disease Research Center,School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Maryam Sahebari sahebarim@mums.ac.ir 10031947532846006630 10031947532846006630 No Rheumatic Disease Research Center,School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Bahram Naghibzadeh naghibzadehb@mums.ac.ir 10031947532846006631 10031947532846006631 No Rheumatic Disease Research Center,School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran. Habibollah Esmaily esmailyh@mums.ac.ir 10031947532846006632 10031947532846006632 No Center for Health Sciences Research, School of Health, Mashhad University of Medical Sciences, Mashhad, Iran