Serum immunoglobulin G as a predictive marker of early renal affection in type-2 diabetic patients: a single-center study

Abstract

Background Chronic hyperglycemia is a characteristic feature of diabetes mellitus and responsible for its long-term microvascular and macrovascular complications. One of the most problematic issues concerning diabetes complications is diabetic nephropathy ending with renal impairment and costly treatment. Defining new biomarkers to detect renal affection in diabetic patients is necessary. So, we aimed to evaluate serum immunoglobulin G (IgG) as a marker of early renal affection. Patients and methods In this study, 50 patients with type-2 diabetes were selected and classified according to their albuminuria and glomerular filtration rate, 25 apparently healthy participants were enrolled as a control group. We measured serum IgG levels in patients and control groups. Results Significant higher mean levels of serum IgG were observed with diabetic patients more than the control group and higher in patients with normoalbuminuria and microalbuminuria with P value less than 0.001 for each, however, significant lowest mean levels of serum IgG in the patients with macroalbuminuria when compared with other degrees of albuminuria, significantly higher mean levels of serum IgG were observed in stage-IV nephropathy when compared with other stages of chronic kidney disease (P≤0.001). There was a significant positive correlation between serum IgG and blood urea, serum creatinine, glycosylated hemoglobin, and albuminuria and proteinuria, and a significant negative correlation with estimated glomerular filtration rate with a significant difference in microvascular and macrovascular complications between the stages of chronic kidney disease and serum IgG levels. Conclusion Serum IgG is a simple test that can be used as a predictive biomarker for early renal affection in type-2 diabetic patients.