The Study And Clinical Application On High-throughput, Low-cost Testing System

Objective To establish a high-throughput, low-cost testing system for health screening in countryside; to discuss the associated factors of elevated serum alanine-aminotransferase (ALT); to establish the reference range of serum ALT in health population.Methods ZS—2SWK multifunctional microplate reader, BIOHIT ePET pipette, the reagent, the precision and accuracy of this system were evaluated with reference to EP-5 (Evaluation of Precision Performance of Clinical Chemistry Devices),EP-6 (Evaluation of the Linearity of Quantitative Analytical Methods),EP-7 (Inference Testing in Clinical Chemistry),EP-9 (Method Comparison and Bias Estimation Using Patient Sample) of NCCLS. Statistical analysis was preformed using the Statistical package for the Social Science. The 95% reference range of serum ALT was estimated by one-tailed test. Moreover, The research on the associated factors with elevated serum ALT was preformed by x~2 test and Logistic regression.Results①ZS—2SWK multifunctional microplate reader has stable light source, small difference of interholes and interchannels , high precision, wide linear range; the dd and d modes of the pipette are reliable; The reagent used has wide linear range,steady end-point,high stability and good resist-interference. The total imprecision and the within-run imprecision are lower than 5% and the average reclaim ratio are all within 100±5%. Compared with the results obtained from OLYMPUS AU5400, the correlation coefficients (r) of this method are all higher than 0.975 and the deviation are all lower than half of the error range allowed by CLIA'88.②By analysing healthy subjects in XiShuangBanNa, we preliminarily establish the reference range of serum ALT in healthy population. The study shows that the activity of serum ALT in male is significantly higher than that in female(t=9.57, P<0.001). The upper limit reference values of serum ALT are 42U/L (in male) and 37 U/L (in female). No significant difference of serum ALT activity is found between groups of 20-59 years old and≥60 years old in male. The upper limit reference values of serum ALT are 34 U/L (in male <20 yeas old) and 44U/L (in male >20 years old). In female, the activity of serum ALT increases significantly with age. The upper limit reference values of serum ALT are 31 U/L (in female <20 years old), 38 U/L( in female 20-59 years old), and 40 U/L( in female≥60years old ).③The following factors are suggested to be significantly associated with elevated serum ALT and independent risk factors: overweight or obesity, fatty liver, elevated hemoglobin(HGB), elevated triglyceride (TG), elevated glucose(GLU) and hepatitis B surface antigen (HBsAg) positive respectively.Conclusions This simple, accurate, high-throughput, low-cost testing system can completely meet the need of health screening in wide countryside. In XiShuangBanNa, the reference ranges of serum ALT for healthy people are < 41.72 U/L in male and <36.61 U/L in female. Furthermore, the elevated serum ALT is strongly associated with metabolic syndrome and fattyliver. Therefore, more attention should be paid to the unscientific dietetic habits.