Open AccessCirculating serum anti-C1q antibody: correlation with clinical and histopathological activity in patients with proliferative lupus nephritis
Author(s) -
Amer A Abeed,
Amel Katat,
Iman E El-Gohary,
O. Hamam
Publication year - 2016
Publication title -
the egyptian journal of internal medicine/the egyptian journal of internal medicine
Language(s) - English
Resource type - Journals
eISSN - 2090-9098
pISSN - 1110-7782
DOI - 10.4103/1110-7782.182950
Subject(s) - lupus nephritis , medicine , anti nuclear antibody , creatinine , nephritis , gastroenterology , systemic lupus erythematosus , renal biopsy , erythrocyte sedimentation rate , urine , urinary system , renal function , antibody , immunology , pathology , autoantibody , disease
In systemic lupus erythematosus (SLE) the prevalence of anti-C1q antibodies (Abs) varies from 30 to 50% and is associated with high clinical activity and, particularly, with renal involvement. Moreover, in the absence of anti-C1q auto-Abs, no lupus nephritis occurs, whereas at least 50% of patients with anti-C1q auto-Abs have or develop lupus nephritis. For lupus nephritis, anti-C1q Abs are as specific as high-avidity dsDNA Ab and capable of closing a diagnostic gap in some cases.Patients and methodsThe present study was conducted on 40 patients with SLE. Patients were classified into group I (20 patients with active proliferative lupus nephritis (LN)), group II (10 patients with inactive LN), and group III (10 patients without nephritis). Laboratory investigations were carried out, including complete blood picture, renal functions (blood urea, serum creatinine, and creatinine clearance), complete urine analysis and urine analysis for dysmorphic red blood cells (RBCs), measurement of 24 h urinary proteins, erythrocyte sedimentation rate (ESR), antinuclear antibody (ANA), and anti-dsDNA, and measurement of serum anti-C1q. Renal biopsy was taken from all patients of group I.ResultsAnti-C1q Abs were significantly higher in group I than in other groups. There were statistically significant positive correlations between anti-C1q Ab level, anti-dsDNA, and percentage of dysmorphic RBCs in urine in group I. There was also a statistically significant positive correlation between anti-C1q Ab level and cellular crescents, leukocyte infiltration, and endocapillary cellularity in the activity index.ConclusionAnti-C1q Ab can be used as an indicator of renal activity in patients with lupus nephritis