Abstract:

Objective To analyze the correlation between urinary total protein（TP） and urinary microalbumin（mAlb）,and to find a method for avoiding the false negativity of urinary mAlb caused by hook effect. Methods The results of urinary mAlb and urinary TP of 1 171 patients were collected,and the correlation between them was evaluated by Spearman correlation analysis. Linear regression equation was established. Totally,35 urine samples with hook effect were validated for urinary mAlb. Results Urinary TP was positively correlated with urinary mAlb（r=0.880,P=0.000）. Taking urinary TP as dependent variable（Y）,urinary mAlb as independent variable（X）,the linear regression equation was established,Y=116.361+1.245X（r²=0.921,P=0.000）. By substituting the urinary mAlb determination values of 35 samples with hook effect（recorded as urinary mAlb_hook） into the equation,urinary TP（recorded as urinary TP_hook） was calculated,urine samples were diluted,and urinary mAlb was determined. The results were recorded as urinary mAlb_dilution. After substituting the equation,the urinary TP value（recorded as urinary TP_dilution） was calculated. There was statistical significance between urinary TP_measuredand urinary TP_hook（P<0.001）,and there was no statistical significance with urinary TP_dilution（P>0.05）. Conclusions According to establishing the linear regression equation between urinary TP and urinary mAlb,whether there is a hook effect in urinary mAlb deterimination can be determined simply. This method is simple and not limited by instruments and reagents,which can be popularized in clinic.

Key words: Microalbumin, Total protein, Urine, Hook effect