Effect of High Speed Centrifugation on the Retesting Results of Serum Markers of Four Blood-Borne Infectious Diseases
AN Zhe;ZHANG Ni;LI Si-peng;LI Miao-xian;WANG Xiang-ling;Department of Clinical Medicine,The Second Hospital Affiliated to Medical School of Xi An Jiaotong University;
Objective To explore the effect of high speed centrifugation on the retesting results of serum markers of four blood-borne infectious diseases. Methods The blood samples with low initial testing-value were collected,in which there were 29 samples with HBs Ag between 0. 05-0. 20 m IU / L,23 samples with HIV-Ag / Ab between 1-2S / CO,24 samples with anti-HCV 1-2S / CO,and 25 samples with anti-TP 1-2S / CO. The blood samples were separated at low and high centrifugation speed respectively in order to be redetected. The retesting results were compared in each item-group and among two method-groups. Results All samples were centrifuged at low speed and high speed respectively and then retested. The positive rates of HBs Ag were 58. 62% and27. 59% respectively and had significant difference( χ2= 5. 069,P = 0. 017). The positive rates of HIV-Ag / Ab were 34. 78% and 8. 70% respectively and had significant difference( χ2= 4. 600,P = 0. 032). The positive rates of anti-HCV were 79. 17% and 75. 00% respectively and had no significant difference( χ2= 0. 118,P =0. 731). The positive rates of anti-TP were 96. 00% and 92. 00% respectively and had no significant difference( χ2= 0. 355,P = 0. 552). Among the 68 positive samples and 33 negative samples which all were retested after low speed centrifugation,the false positive rate and false negative rate were 30. 88%( 21 /68) and 12. 12%( 4 /33) respectively. With low speed centrifugation,the retesting positive rates were 48. 08% in the sandwichmethod group and 87. 26% in the indirect-method group,and the difference was significant( χ2= 18. 055,P =0. 000). With high speed centrifugation,the retesting positive rates were 19. 23% in the sandwich-method group and 83. 67% in the indirect-method group,and the difference was also significant( χ2= 41. 911,P =0. 000). As the speed increasing,the retesting positive rates among sandwich-method group and indirectmethod group decreased 28. 85% and 3. 59% and had significant difference( χ2= 8. 246,P = 0. 004).Conclusion High speed centrifugation could significantly decrease the retesting positive rate of HBs Ag and HIVAg / Ab. The low speed centrifugation could cause false positive and false negative. The effect of centrifugation speed on the retesting results differs between sandwich-method and indirect-method.
【CateGory Index】： R446.6