title: Using Elecsys® HIV Combi PT assay to identify acute and early HIV infection in a teaching hospital of southwest China.
abstract: This study is the first attempt to evaluate the use of the Elecsys® HIV combi PT assay in identifying acute and early HIV infection in southwest China. We also analyzed the extent of cutoff ratios overlap between false-positive and true-positive results to aid the identification of HIV infection, using samples from the West China Hospital in Chengdu, Sichuan Province from April 2012 to December 2013. Reactive results from a screening test were retested and all repeatedly reactive samples - if available - were confirmed with Western blot, HIV-1 p24 antigen, or HIV-1 RNA. Of 241,840 samples screened, the Elecsys® HIV combi PT assay identified 54 patients with acute and early HIV infection; 99.8% cases with cutoff index ratios ≥50 were proved to be true-positive HIV infection and 95.6% cases with cutoff index ratios <15 were falsely positive. In conclusion, the Elecsys® HIV combi PT assay can identify acute and early HIV infection, including those who might have been missed by third-generation HIV screening assays and Western blot. However, cutoff index ratios <15 are not always false-reactive results; a definitive result cannot be attained without further confirmation. In resource-poor regions where a HIV-1 nucleic acid test may be unaffordable, detection of HIV-1 p24 antigen can be an alternative strategy to diagnose HIV infection in individuals with a negative or indeterminate Western blot.
authors.affiliation: Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Siyuan
authors.initials: S
authors.lastname: Zhu
authors.affiliation: Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Dongdong
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Jingna
authors.initials: J
authors.lastname: An
authors.affiliation: Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Qixia
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, China.
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, China taochuanmin@sina.com.
authors.forename: Chuanmin
authors.initials: C
authors.lastname: Tao
mesh_terms: D000328:Adult; D015153:Blotting, Western; D002681:China; D042241:Early Diagnosis; D005260:Female; D015483:HIV Antibodies / Q000097:blood* / Q000276:immunology; D016655:HIV Core Protein p24 / Q000097:blood* / Q000276:immunology; D015658:HIV Infections / Q000175:diagnosis*; D015497:HIV-1 / Q000302:isolation & purification*; D006784:Hospitals, Teaching; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D012367:RNA, Viral / Q000097:blood; D012680:Sensitivity and Specificity
chemical_list: D015483:HIV Antibodies; D016655:HIV Core Protein p24; D012367:RNA, Viral
keywords: AIDS; Elecsys® HIV combi PT assay; HIV; acute and early HIV infection; diagnosis; testing