Urine β 2-Microglobolin in the Patients with Congenital Heart Disease

Background: This study aimed to evaluate the renal tubular function in the patients with congenital heart disease using β₂-microglobulin.

Methods: In this case-control study, based on oxymetry, the patients with congenital heart disease were divided into two groups of cyanotic (n=20) and acyanotic (n=20). Congenital heart disease was diagnosed by echocardiography. Healthy individuals within the same age and sex groups were used as controls. Na⁺, β₂-micro globulin, creatinine (Cr), and β₂-microglobulin/Cr ratio were measured in random urine samples and the results were compared to the same parameters in the control group using Tukey, One-Way ANOVA, and X² tests.

Results: Based on the study results, urine sodium in the patients with cyanotic heart disease was significantly different from that of the controls (P=0.023). The results also revealed a significant difference between the two groups with congenital heart disease regarding urine β₂-microglobulin (P=0.045).
In addition, the patients with cyanotic heart disease were significantly different from those with acyanotic heart disease and the controls regarding urine β₂-micro globulin/Cr ratio (P=0.012 and P=0.026, respectively).

Conclusions: The results of this study demonstrated that renal tubular dysfunction began in the patients with congenital heart disease, especially in those with cyanotic congenital heart disease. Besides, early diagnosis before cardiac surgery leads to better control of renal tubular disease.