Parallel enzyme-linked immunosorbent assay screening for human immunodeficiency virus among blood donors in five Chinese blood centres: a retrospective analysis

Seroprevalence of Transfusion Transmissible Infections and Associated Risk Factors in Hospitalized Patients before Transfusion in Jinling Hospital Nanjing University: A Three-Year Retrospective Study

Transfusion-transmitted infections (TTIs), such as hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), and treponema pallidum (TP), must be detected before blood transfusion. However, few studies have been conducted on the prevalence and accuracy of positive results in hospitalized patients. The purpose of this study was to investigate the real seroprevalence of TTIs among patients before blood transfusion and analyze the characteristics of false-positive results in Jinling Hospital, Nanjing University, China. TTI results were collected from medical records and analyzed retrospectively. Additionally, we also used confirmatory assays to verify the accuracy of positive results. The overall prevalence of TTI was 8.96%, which was related to gender and age. The real positive rates were 86.67% (HBV), 35.09% (HCV), 20.75% (HIV), and 100% (TP). Our results also showed that high-speed centrifugation can reduce the false-positive rate of HBsAg. In summary, the results demonstrated that the positive rates of TTIs in hospitalized patients are higher than those in the general population. We also confirmed the existence of false-positive results in serological screening for TTIs. The method of processing specimens through high-speed centrifugation could reduce the false-positive results of detecting antigens effectively.

An alternative strategy to western blot as a confirmatory diagnostic test for HIV infection

BACKGROUND

In China, western blot (WB) is the recommended procedure for the diagnosis of HIV infection. However, this technique is time consuming and labor intensive, and its complexity restricts wide application in resource-limited regions.

OBJECTIVE

The aim of this study was to evaluate the efficacy of a dry blood spots (DBS)-urine paired enzyme-linked immunosorbent assay (ELISA) test, instead of WB, for HIV antibody detection.

STUDY DESIGN

Plasma, DBS, and urine samples were collected from 1213 subjects from different populations. Two diagnostic testing strategies were conducted in parallel. The equivalence of the paired ELISA and WB strategies was assessed.

RESULTS

A diagnosis of HIV was determined in 250 subjects according to the paired ELISA test, and in 249 according to the WB strategy. The discordant case was judged HIV-positive during follow-up. In total, 18 subjects were diagnosed with possible HIV using the paired ELISA test, among whom, 11 subjects tested negative with WB, and one was confirmed to be HIV-positive during follow-up. For the remaining 945 subjects, both strategies indicated a negative result. The kappa test indicated good conformity (kappa=0.954) between the two diagnostic strategies.

CONCLUSION

The DBS-urine paired ELISA could be applied as an alternative to WB in HIV diagnosis, which would be valuable in resource-limited regions owing to the associated affordability and ease of use.