Assessment of the infectivity of corneal buttons taken from hepatitis B surface antigen seropositive donors

Maximize Donor Cornea Use in a Hepatitis B Endemic Area via Serology Matching

BACKGROUND

This study aims to investigate the rationality of the allocation guidelines in a hepatitis B endemic area that uses corneas from hepatitis B donors.

METHODS

Under Taiwan's current guidelines, corneas donated from hepatitis B surface antigen (HBsAg)(+) donors can be allocated to HBsAg(+) or hepatitis B surface antibody recipients. From January 1, 2015, to December 31, 2019, corneas donated to National Taiwan University Hospital were divided into HBsAg(+), HBsAg(-)/hepatitis B core antibody (anti-HBc)(+), and HBsAg(-)/anti-HBc(-) groups. Hepatitis B virus (HBV) DNA extracted from corneoscleral rims was quantified by polymerase chain reaction and correlated with donor serum HBsAg, anti-HBc, and HBV DNA. Recipients of HBV DNA(+) grafts were called back for serology and serum HBV DNA tests.

RESULTS

The corneoscleral HBV DNA of 170 corneas (113 donors) was quantified, of which 45 corneas were from 28 HBsAg(+) donors, 87 were from 57 HBsAg(-)/anti-HBc(+) donors, and 38 were from 28 HBsAg(-)/anti-HBc(-) donors, and HBV DNA was detected in 80.0%, 9.2%, and 0% of the corneoscleral rims in each group. Donor anti-HBc(+) provided the highest sensitivity (1.00) and negative predictive value (1.00) for corneoscleral HBV DNA. Twenty-eight of 40 recipients (70%) using HBV DNA(+) grafts were called back, and none developed hepatitis in follow-up periods ranging from 6 to 55.5 mo.

CONCLUSIONS

Donor anti-HBc should be tested routinely with HBsAg. Allocating corneas from HBsAg(+) or anti-HBc(+) donors to HBsAg(+) or hepatitis B surface antibody recipients maximizes cornea usage from hepatitis B donors without compromising transplant safety in a hepatitis B endemic setting.

Hepatitis B transmission by cell and tissue allografts: How safe is safe enough?

More than 2 million human tissue transplants (bone, tendon, cartilage, skin, cornea, amniotic membrane, stem cells, heart valve, blood vessel, etc.), are performed worldwide every year. Cells and tissues are shared between countries which have different regulations and laboratory equipment and represent a risk of hepatitis B virus (HBV) transmission that has become a global safety concern. While the risk of transfusion-transmitted HBV infection from blood donations has been estimated, the rate of HBV transmission from donors to recipients of allografts is unknown and varies between different tissues. There are various important ways of reducing the transmission risk, but donor screening and donor testing are still the main factors for preventing HBV transmission. HBV detection is included in the routine screening tests for cell and tissue donors. The standard test for preventing transplant-transmitted hepatitis B is the hepatitis B surface antigen. The implementation of methods involving nucleic acid amplification and the new generation of reactives to detect viral antibodies or antigens with an immunoassay, has increased the sensitivity and the specificity of the screening tests. The objective of our research was to review the literature and critically analyse the different steps for avoiding HBV transmission in cell and tissue donors, focusing on the screening tests performed.

Risk factors for infectious disease in corneal transplant screening

PURPOSE

To identify potential medical and behavioral risk factors associated with infectious disease seropositivity in potential corneal donors using an extensive questionnaire completed by the next of kin.

METHODS

Retrospective review of medical history and behavioral risk assessment questionnaire and microbiology data for potential corneal donors seropositive for hepatitis B, hepatitis C, human immunodeficiency virus, human T-cell leukemia virus and syphilis as compared to controls.

RESULTS

Tobacco use, cigarette smoking, chest pain and heart disease are each associated with corneal donor seropositivity (P < 0.05). Vaccination in the last twelve months is inversely associated with infectious disease (P < 0.05). Statistically significant factors associated with hepatitis C positive donors include: cigarette use, illicit drug use, chest pain, cardiac medications, kidney stones and lung disease (P < 0.05). Factors most often associated with transmission of this disease panel (such as intravenous drug use, sexual contact with prostitutes and history of blood transfusion) are often not identified by the next of kin in the questionnaire.

CONCLUSIONS

While there are questionnaire identified risk factors associated with seropositivity in this study, their clinical usefulness is unclear. Many factors crucial to the elimination of potentially infectious donor tissues are not identified in the posthumous history typically completed by next of kin. These questionnaires alone do not provide exclusion criteria for elimination of potentially infectious tissues from the donor pool.

Feline leukemia virus detection in corneal tissues of cats by polymerase chain reaction and immunohistochemistry

OBJECTIVES

To determine the presence of feline leukemia virus (FeLV) in the corneas of FeLV-infected cats.

ANIMALS STUDIED

Thirty-four random source cats.

PROCEDURES

Seventeen cats were found positive for FeLV serum p27 antigen by enzyme-linked immunosorbent assay (ELISA). Twelve ELISA positive cats were also positive on peripheral blood samples by immunofluorescent antibody (IFA) testing. Seventeen ELISA negative cats served as negative controls. Full thickness corneal specimens were collected from the left cornea of all cats and analyzed for FeLV proviral DNA and gp70 antigen by polymerase chain reaction (PCR) and immunohistochemical (IHC) testing, respectively.

RESULTS

Eleven (64.7%) positive corneal PCR results were obtained from 17 ELISA positive cats. Of 12 cats that were both ELISA and IFA positive on peripheral blood, 10 (83.3%) had positive corneal PCR results. All corneal tissues from ELISA negative cats were PCR negative. IHC staining of corneal sections revealed the presence of FeLV gp70 in corneal tissues of nine (52.9%) ELISA positive cats. Of the 12 cats that were both ELISA and IFA positive on peripheral blood, eight (66.7%) had positive corneal IHC results. Positive IHC staining was localized to the corneal epithelium. Corneal tissues of all ELISA negative cats and all IFA negative cats were negative on IHC testing.

CONCLUSIONS

FeLV antigens and proviral DNA are present in corneal tissues of some FeLV-infected cats. Screening corneal donors for FeLV infection is warranted.