The usefulness of serum beta-2 microglobulin as a biomarker for evaluating renal function decline in type II diabetes mellitus

Abstract
Background and objective: Serum beta-2 microglobulin (β2M) has been used as a useful clinical marker of chronic kidney dysfunction. The current study aims to evaluate the diagnostic accuracy of β2M for the early detection of diabetic nephropathy among Iraqi patients with type II diabetes mellitus. Methods: The study included 84 participants divided into four groups, three of them were type II diabetics and the fourth is the healthy individuals’ (control) group. The diabetic’ subgroups were named according to the Micral test as: normoalbuminuria (21 patients), microalbuminuria (21 patients), and macroalbuminuria group (21 patients). The control group included 21, age- and sex-matched, healthy participants. Biochemical markers for diabetes mellitus as well as β2M were determined for each participant and then were analyzed statistically. Results: The serum β2M of normoalbuminuria group was (2.86±0.95 µg/mL), microalbuminuria group was (5.06±1.97 µg/mL) and macroalbuminuria group (3.6±1.59 µg/mL). The results showed significant increase (p˂0.05) in the β2M level of microalbuminuria group when compared with that of normoalbuminuria and macroalbuminuria groups. In addition, a highly significant increase (p˂0.01) in β2M concentration was observed in microalbuminuria group when compared with that of the control group. Conclusions: β2M can be used as a useful biomarker for the early detection of diabetic nephropathy.