Prevalence of Microalbuminuria in Clinically Healthy Siblings of patients of SLE with and without Lupus Nephritis

Abstract

Systemic lupus erythematosus (SLE) is a chronic, relapsing, inflammatory, and often multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidney and serosal membranes. Lupus nephritis is a severe consequence of SLE and an important driver of morbidity and mortality in SLE. Lupus nephritis affects ~40–70% of patients with SLE, with the exact incidence dependent on ethnicity, age group, and gender. Both systemic and intra-renal events are important in the pathogenesis of lupus nephritis. Microalbuminuria is defined as excretion of between 30 and 300 mg of albumin a day in the urine of 20-200 ug/min of albumin, Less than 30 mg is insignificant, Albumin levels below 300 mg a day is too small to be detected by standard protein dipstick testing, so any positive result is more severe than microalbuminuria. Possible familial tendency of SLE is still a mysterious question which has not been properly answered in the literature till now, yet there’s growing evidence that possible genetic aberration in families may play a significant pathogenic role. Our study aimed at assessing microalbuminuria in siblings of a randomly selected 60 cases with SLE under regular follow up in our clinic in ASU, candidates were divided into 2 age and sex matched equal groups based on history of SLE nephritis in cases. We found that siblings of patients with nephritis had a relatively higher rate of microalbuminuria though no statistical significance could be obtained. Microalbuminuria was also found to be related more to female gender, and ANA positivity in siblings of patients with nephritis.