Human immunodeficiency virus p24 antigen testing in cornea donors

Screening algorithms for HBV, HCV, HIV and syphilis in an anatomical donation program

BACKGROUND

Users of anatomical donors are at risk of exposure to bloodborne pathogens. This study evaluated screening algorithms for hepatitis B and C virus, human immunodeficiency virus and Treponema pallidum during donor allocation and assessed the impact of postmortem time on hemolysis and how hemolysis affects test results and donor discard rate.

METHODS

From 2011 to 2018, demographic data of anatomical donors, time of postmortem blood sampling, presence of sample hemolysis, serological test results (negative; active infection; false reactive screening test; historic infection; inconclusive; technically impracticable) and the actual donor allocation were collected.

RESULTS

Donors (n = 537) had a mean age of 77.53 ± 13.67 (24-103) year. Nine (1.68%) had laboratory test results indicative for active infection for hepatitis B (n = 1) and C virus (n = 2), human immunodeficiency virus (n = 5) and T. pallidum (n = 1). Negative screenings ranged from 74.67 to 97.58%, depending on the pathogen. According to the original screening algorithms, 479 (89.20%) donors should have been accepted. In practice, a donor acceptance rate of 91.20% was found. Analysis of potential donor allocation interpretation obstacles resulted in simplification of the in-house laboratory testing algorithms and addition of a nucleic acid test to increase the reliability for identification of active (acute) human immunodeficiency virus infection. Hemolysis was more common when sampling was performed more than 24 h after death (p < 0.001). Hemolytic samples more frequently showed a reactive or indeterminate human immunodeficiency virus test result (p < 0.001). Screening for human immunodeficiency virus and T. pallidum was technically more impracticable when hemolysis was present (p = 0.042 and p = 0.003, respectively). Donors with hemolytic blood samples were more often discarded (46.88%) compared to bodies with non-hemolytic samples (6.32%) (p < 0.001).

CONCLUSIONS

Despite the implementation of donor screening algorithms, a significant number of bodies have an inconsistent allocation. New algorithms, to be evaluated in future research, were suggested. Early postmortem blood sampling is key as hemolysis can influence certain test results and donor allocation.

Seropositivity of blood samples of 31,355 cornea donors from a tertiary care network of eye banks

PURPOSE

To evaluate the seropositivity of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV) and syphilis from blood samples of cornea donors and assess correlation between seropositivity for HIV and syphilis.

METHODS

Retrospective analysis of blood samples of 31,355 cornea donors for HIV, HBV, HCV, and syphilis was performed. Postmortem blood samples were analyzed by a rapid screening test for anti-HIV envelope antibodies against HIV 1 and 2, HBV surface antigen, antibody to HCV and anti-cardiolipin antibodies for syphilis by rapid plasma reagin test.

RESULTS

The overall seropositivity rate was 4.28% (1343/31,355 donors). All positive donors were reactive for a single serological test. The seropositivity rate for HIV was 0.93% (95% CI 0.83-1.04%), for HBsAg was 1.56% (95% CI 1.43-1.7%), for HCV was 1.19% (95% CI 1.08-1.33%) and for syphilis was 0.59% (95% CI 0.52-0.69%). The trends in seropositivity rates showed a decline for three viral markers: HIV (2010, 1.17% to 2018, 0.72%, p = 0.02), HBsAg (2010, 1.98% to 2018, 1.05%, p = 0.0006) and HCV (2010, 1.32% to 2018, 0.43%, p < 0.0001). The seropositivity rates for syphilis showed a progressive increase when compared to baseline (2010, 0.14% to 2018, 1.14%, p < 0.0001). There was no relationship between seropositivity for HIV and syphilis (p = 0.18).

CONCLUSIONS

The overall seropositivity for HIV, HBV, HCV and syphilis was 4.28%. Seropositivity was highest for HBV. The study did not find correlation between seropositivity of HIV and syphilis.

Factors influencing the virological testing of cornea donors

To assess the influence of donor, environment, and logistical factors on the results of virological testing of blood samples from cornea donors.Data from 670 consecutive cornea donors were analyzed retrospectively. Logistic regression analysis was used to assess the influence of different factors on the results of virological testing of blood samples from cornea donors.The mean annual rate of donors with serology-reactive or not evaluable result was 14.8% (99 of 670) (range 11.9%-16.9%). The cause of donor death by cancer increased the risk of serology-reactive or not evaluable result (P = .0300). Prolonged time between death and post mortem blood removal was associated with a higher rate of serology-reactive or not evaluable result (P < .0001). Mean monthly temperature including warmer months, differentiating between septic and aseptic donors, sex, and donor age had no significant impact on the results of virological testing of blood samples from cornea donors.The cause of donor death by cancer and a prolonged time between death and post mortem blood removal seem to be mainly responsible for serology-reactive or not evaluable result of blood samples from cornea donors. The percentage of discarded corneas caused by serology-reactive or not evaluable result may be reduced by shortening the period of time between death and post mortem blood removal.

Serological Viral Testing of Cadaveric Cornea Donors

BACKGROUND

Cornea graft recipients are exposed to viral transmission from the donor. Cadaveric donor serum is often of poor quality and frequently yields falsely positive results in serological assays that may result in the graft being needlessly discarded.

OBJECTIVE

We examined the influence of the time of blood collection after death, and the macroscopic aspect of serum, on serological test results in cadaveric cornea donors.

METHODS

Five hundred sixty-five consecutive cadaveric cornea donors were systematically tested for serological markers of human immunodeficiency virus type 1 and 2, human T-cell leukemia virus type 1, hepatitis B and hepatitis C viruses (HCV). We studied the influence of the macroscopic aspect of the donor's serum and the time of blood collection after death on the results of serological testing and on the subsequent decision to use or discard the graft.

RESULTS

Twenty-one and a half percent of corneas were rejected on the basis of virological test results. We found significant relationships between the macroscopic aspect of serum at the time of testing and: (i) a positive, equivocal or discrepant result of immunoassays, for all markers except anti-HCV antibodies, (ii) non acceptance of cornea grafts, and (iii) the time of blood sampling after death.

CONCLUSIONS

The macroscopic aspect of postmortem blood samples is the best predictor of the specificity of serological testing in cornea donors. Serological results should be interpreted with care when serum is macroscopically abnormal, and cadaveric donors should not be sampled more than 12 hr after death.

The rate of anti-HIV seropositivity among donated cadavers: experience in a cadaver donation center

Cadavers are crucial for the medical education provided by medical schools. However, currently, donation is the only way to obtain cadavers for education in Thailand. Moreover, some traditional beliefs result in insufficient numbers of cadavers. Apart from finding donors, the occupational health of the workers in the cadaver donation center and the users, the medical students, residents, and staffs should be addressed. Screening for anti-HIV in donated organs is the current trend in transplantation medicine. Therefore, screening for anti-HIV in donated cadavers is useful. Here, we report the rate of anti-HIV seropositivity in cadavers in a 1-year period in our setting, the largest Thai Red Cross Society hospital. Of the total 84 cadavers received, two cadavers (2.4%) were anti-HIV seropositive. With the increasing rate of anti-HIV, screening for anti-HIV serology in donated cadavers for medical teaching is of great benefit.