Background: Systemic lupus erythematosus (SLE) is an autoimmune disease. Few biomarkers for SLE have been validated and widely accepted for the laboratory follow-up of inflammatory activity. In SLE patients, with lupus nephritis (LN), complement activation leads to fluctuation of serum C3 and C4 that are frequently used as clinicalm biomarker of disease activity in SLE. Patients and Methods: In this study the number of patients were 37, seven patients were excluded for incomplete data collection, 28 were females ,2 were males. The duration of the study is two years from 2015 to 2017. Patients were considered to have SLE and LN according to American College of Rheumatology (ACR) criteria, and International Society of Nephrology/ Renal Pathology Society (ISN/RPS). All patients were evaluated withm clinical presentation, laboratory investigations. Our patients underwent kidney biopsy according to standard procedure by Kerstin Amann, and their tissue specimens were studied in the laboratory with light microscope (LM) and immunofluorescence microscope reagents. The relationship between the serological markers and immunofluorescence deposits in kidney biopsy of all patients were studied using the statistical analysis of Pearson correlation and single table student's T test. A P value 0.05 was considered statistically significant. Results: The granular pattern of IF deposits was present in all LN patients, and in more than two third of patients these IF deposits presented in glomerular, tubular, and mesangium sites. While less than one third of patients had IF deposits in the mesangium only. There was no statistically significant correlation between serum ANA, anti-dsDNA, and IF deposits of different types. There was significant correlation between serum C3 and C4 hypocomplementemia and IgG immune deposits in kidney biopsy, and there was significant relationship between serum C3 hypocomplementemia and full house immunofluorescence (FHIF) deposits inm kidney biopsy.Conclusions:Immunofluorescence deposits is mainly granular pattern in LN patients. There was no significant association between serum ANA, anti-dsDNA, and immune deposits in kidney tissue. Immunofluorescence deposits of IgG type correlates significantly with serum C3 and C4 hypocomplemetemia, and these immune deposits in association with low complement levels correlates with LN flare. There was significant correlation between C3 hypocomplementemia and FHIF.
Indications and considerations for kidney biopsy: an overview of clinical considerations for the non-specialist
