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Since the beginning of the COVID-19 pandemic there has been some debate regarding the risk of transmission through tissue transplantation and tissue banking processes. To analyze the changes that SARS-CoV-2 has caused regarding the harvesting of corneal donor tissue and eye bank activities in Germany. A questionnaire was provided to 26 eye banks in Germany, consisting of questions about adaptations made in the screening of potential donors and the harvesting of corneal tissue following the pandemic spread of SARS-CoV-2. Eighteen eye banks actively reduced recruitment of donors and two banks ceased all activity. Additional diagnostic screening was performed in eight banks, using conjunctival swabs and/or nasopharyngeal swabs. In six eye banks, additional protective measures, such as FFP2 masks and/or facial shields, were implemented. Overall, a mean reduction in the number of obtained donor tissues of 17% was observed. Conjunctival and/or nasopharyngeal swabs of donors have been implemented by a minority. Reasons for not performing additional tests may be moderate sensitivity and lack of validation for postmortem use of RT-PCR testing. Also, the hazard of SARS-CoV-2 entering the corneal donor pool with subsequent transmission might be perceived as theoretical. Face shields provide a sufficient barrier against splash and splatter contamination but may be insufficient against aerosols. Additional face masks would provide support against aerosols, but it remains debatable if corneal harvesting can be considered an aerosol-producing procedure. In the future we expect to see changes in current guidelines because of a surge in scientific activities to improve our understanding of the risks involved with cornea donation in the COVID-19 pandemic, and because current practice may reduce the availability of donor corneas due to new exclusion criteria while the demand remains unchanged. [ABSTRACT FROM AUTHOR]

Background: Since blood culture bottles are validated by the manufacturer for blood only, an additional validation for the use with fluids of tissue preparations is necessary. Methods: Two 10-ml samples of cornea culture medium, histidine-tryptophan-ketoglutarate (HTK) solution, or Ringer solution at the end of femur head thermo-disinfection were given into blood culture bottles (BD BACTECTM Plus Aerobic/F, Anaerobic/F for cornea culture medium and BD BACTECTM Standard Aerobic/ Anaerobic for HTK and Ringer solution) and subsequently spiked with 10-100 colony forming units (CFU) of bacteria or fungi (aerobic bacteria: Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa; anaerobic bacteria: Clostridium sporogenes; fungi: Candida albicans, Aspergillus brasiliensis) according to the European Pharmacopoeia Chapter 2.6.1. Results: All tested bacteria and fungi could be detected in all solutions. All positive and negative controls were tested correctly. Compared to the positive controls, the microbial growth was delayed in the antibiotic-containing cornea culture medium, and negative in two cases of B. subtilis spiking. Conclusion: The use of BACTECTM blood culture bottles seems to be a suitable method for microbiological testing of HTK solution, Ringer solution, and, with limitations, also for testing of the antibiotic-containing cornea culture medium. [ABSTRACT FROM AUTHOR]

Background: Corneas needed for keratoplasty can be harvested using two techniques: whole globe enucleation and in situ excision of the corneoscleral disc. This study evaluates the rate of microbial contamination of the donor cornea organ culture medium according to the method of retrieval. Methods: All donor corneas of our cornea bank received between January 1, 2001 and December 31, 2009 put into organ culture and microbiologically tested were prospectively analyzed for microbial contamination of the organ culture medium. Results: 2,805 donor corneas could be included in this study in total. 975 of them were retrieved by whole globe enucleation (group 1) and 1,830 by in situ corneoscleral disc excision (group 2). 15 corneas of group 1 (1.5%) and 46 corneas of group 2 (2.5%) showed a contamination of the organ culture medium. The difference was shown not to be statistically significant (p = 0.082). Conclusion: The rate of microbial contamination in organ-cultured donor corneas does not seem to be dependent on the method of their retrieval. [ABSTRACT FROM AUTHOR]

Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht.