Seropositivity rates of blood samples of 31355 cornea donors from a tertiary care network of eye banks

Abstract

Purpose : Screening tests for human immunodeficiency virus (HIV), hepatitis C virus (HCV) hepatitis B virus (HBV), and syphilis are routinely conducted for blood samples from cornea donors. Seropositivity for syphilis has been used as a surrogate indicator for detection of human immunodeficiency virus (HIV) in the window period. We report the seropositivity rates in blood samples of cornea donors, collected from a network of four eye banks of a tertiary eye care institute and correlation between seropositivity for HIV and syphilis.

Methods : Retrospective chart review of blood samples from 31,355 corneal donors screened for HIV I, Hepatitis B surface antigen (HbSAg), HCV and syphilis between the years 2010-18, as per guidelines recommended by the competent authority, prior to tissue utilization. A blood sample of 10 ml was collected at the time of cornea retrieval for serology tests. HIV 1 was screened using ELISA or rapid immunochromatography test, HbSAg and HCV were screened by one step card method, syphilis was screened for anticardiolipin antibody by rapid plasma reagin test.

Results : The overall seropositivity rate was 4.28% (1343/31355 donors). All positive donors were reactive for a single serological test. The seropositivity rate for HIV I was 0.92%(95% CI 0.008-0.010), HbsAg 1.55%(95% CI 0.014-0.017), HCV 1.19%(95% CI 0.011-0.013), Syphilis 0.59%(95% CI 0.005-0007). The Pearson correlation coefficient between proportions of seropositivity for HIV versus syphilis calculated over nine years showed a weak negative correlation of -0.16(p 0.68). The seropositivity varied across different eye banks.

Conclusions : Serological screening of blood samples are important quality parameters of donor screening for suitability of transplantation. There was a weak correlation between seropositivity for syphilis and HIV. Samples that were negative for HIV may be positive for syphilis hence there is a chance to miss out this cohort if we discontinue screening for syphilis. The seropositivity rates vary considerably across the network of eye banks. This may possibly be due to geographical variations in the prevalence of disease in the community.

This is a 2020 ARVO Annual Meeting abstract.