The Influence of Donor and Recipient Gender Incompatibility on Corneal Transplant Rejection and Failure.

In vascularized organ transplants, gender mismatches have higher rates of immunological rejection. We investigated the influence of gender incompatibility, including H-Y incompatibility, on corneal transplant graft rejection and failure. Patients were included who had undergone a first corneal transplant for keratoconus (KC), Fuchs endothelial dystrophy (FED), pseudophakic bullous keratopathy (PBK), infection and other indications. A Cox regression model was fitted for each indication to determine factors affecting graft failure and rejection at 5 years. The impact of gender, including H-Y, matching was analyzed after accounting for other factors, including known risk factors. Of 18 171 patients, 4314 had undergone a transplant for FED, 4783 for KC, 3669 for PBK, 1903 for infection and 3502 for other disorders. H-Y mismatched (male [M]→female [F]) corneas were at greater risk of graft failure or rejection. For FED, F→F were 40% less likely to fail (p < 0.0001) and 30% less likely to reject (p = 0.01); M→M were 20% less likely to fail (p = 0.04) and 30% less likely to reject (p = 0.01). For KC, M→M matched corneas were 30% less likely to fail (p = 0.05) and 20% less likely to reject (p = 0.01) compared with H-Y mismatches. H-Y antigen mismatched (M→F) patients were at greater risk of rejection or graft failure.

The impact of donor age and endothelial cell density on graft survival following penetrating keratoplasty.

PURPOSE: To determine if donor age and preoperative endothelial cell density (ECD) affect corneal endothelial failure following penetrating keratoplasty (PK). METHODS: Preoperative and postoperative data for PKs performed in the UK between April 1999 and March 2012 were analysed. Donor age was split into three groups (0-60, 61-75 and >75 years) and donor ECD was split into three groups (≤2400, 2401-2600 and >2600 cells/mm2). Cox proportional hazards regression was used to determine whether the selected subgroups of donor age and donor ECD have an impact on endothelial failure and a systematic analysis of the interaction between donor ECD and donor age was conducted. The analysis was stratified for primary corneal diagnosis (Fuchs endothelial dystrophy (FED), pseudophakic bullous keratopathy (PBK) and other) and corrected for potentially confounding factors (human leukocyte antigen matching, donor trephine diameter, deep vascularisation, the occurrence of reversible rejection episodes and receipt of systemic antiviral medication, long-term steroids or other immunosuppressive agents). RESULTS: A total of 9415 patients, from the National Health Service Blood and Transplant UK Transplant Registry, who received their first PK for visual reasons were included in this study. The overall 5-year graft survival rate due to endothelial failure was 89%. Survival rates in recipients with FED, PBK and 'all other indications' were 95%, 83% and 89%, respectively. Our analysis shows that donor ECD did not affect outcome following corneal graft within the preselected categories, irrespective of diagnosis and after allowing for any potential confounding factors. Furthermore, HRs for each level of donor ECD, relative to >2600 cells/mm2, for each combination of age group and indication, were not statistically significant. CONCLUSIONS: We were unable to detect a significant effect of donor age, up to 90 years, and preoperative donor ECD, above the lower limit of 2200 cells/mm2, on endothelial failure at 5 years following PK.

Tissue and corneal donation and transplantation in the UK.

NHS Blood and Transplant (NHSBT) was established in 2005 as a Special Health Authority when the National Blood Authority and UK Transplant merged. This helped to bring tissue banking and organ transplantation services under one umbrella organization. This merger means that ~!95% of all deceased donors (whether tissue, organ or both) are now facilitated by one organization. NHSBT Tissue Services is the largest tissue establishment in the UK, and is a multi-tissue bank that specializes in the consent, retrieval, processing, storage, and dispatch of donated tissue coordinated from a purpose built, state-of-the-art tissue bank in Liverpool. Tissue donations can come from either tissue-only donors or solid organ donors who also donate tissue. Annually there are ~450 multi-tissue donors and 2500 eye donors in the UK, resulting in many thousands of transplants, including 3564 cornea transplants in 2010-2011. The separation of tissue- and organ-specific donors is largely artificial, and while organ transplantation can be life-saving, tissue transplantation can also have a dramatic effect on a patient's quality of life. It is hoped that all donors, both organ and tissue, will be recognized for the gift they make to society after their death.

Antiviral treatment following penetrating keratoplasty for herpetic keratitis.

PURPOSE: To assess the effect of antiviral treatment on corneal graft survival following penetrating keratoplasty for herpetic keratitis. METHODS: Retrospective cohort study of 454 patients receiving primary penetrating keratoplasties (PKs) for viral infection reported to NHS Blood and Transplant (NHSBT) between April 1999 and June 2005. Follow-up data were available on 403 PKs. Kaplan-Meier survival estimates were used to determine graft survival for the three treatment groups: no medication, topical antiviral, and oral antiviral medication. A Cox regression model was used to investigate the combined effects of all additional factors on graft failure. The model was fitted using all pre-operative factors first and then post-operative factors including type of antiviral medication were included. RESULTS: Patients who received oral antiviral medication post-operatively had consistently better graft survival than those receiving no medication or only topical medication. Patients receiving oral antivirals were less than a third as likely to have a failed graft at 5 years compared with those on no antiviral medication (relative risk (RR) 0.3, CI: 0.2-0.7, P=0.002). Other factors that were found to influence the risk of graft failure were the presence of deep corneal vascularisation (P=0.009), PK performed for therapeutic reasons (P=0.03), large diameter grafts (P=0.04), and experiencing a rejection episode (P=0.003). CONCLUSION: Oral antiviral treatment reduces the risk of graft failure in patients undergoing primary PK for herpetic keratitis and should be routinely used in this group of patients post-operatively unless contra-indicated.

The visual and refractive outcomes of combined and sequential penetrating keratoplasty, cataract extraction, and intraocular lens insertion.

PURPOSE: The aim of this study was to investigate the visual and refractive outcome of combined penetrating keratoplasty, cataract extraction, and intraocular lens insertion (triple procedure) compared with cataract surgery following penetrating keratoplasty (sequential surgery). METHODS: Retrospective cohort study of 1256 first penetrating keratoplasty for Fuchs' dystrophy performed between April 1999 and December 2005. In all, 1202 triple and 54 sequential procedures were reviewed. At 1 year, refractive outcomes were available for 499 triple procedure and 26 sequential surgery eyes. At 2 years, data were available for 264 triple procedure and 10 sequential surgery eyes. At 1 and 2 years postoperatively, graft survival, best-corrected visual acuity (BCVA), spherical equivalent, and cylindrical error were recorded. chi(2)-Tests were used to compare visual outcomes between the two groups. RESULTS: At 1 year after triple procedure surgery, 61% of eyes attained BCVA of >or=6/12, with 47% of eyes within+/-2 D of emmetropia. After sequential surgery, 59% achieved BCVA of >or=6/12 with 67% of eyes within+/-2 D of emmetropia (=0.05). Mean spherical equivalent (MSE) at 1 and 2 years after triple procedure was +1.20 D (SD 5.45) and +0.15 D (SD 3.58), respectively. MSE following sequential surgery at 1 and 2 years was +0.08 D (SD 3.06) and -1.50 D (SD 3.14), respectively. Mean refractive cylinder after combined surgery was +4.16 D (SD 5.11) and +3.91 D (SD 2.79) at 1 and 2 years, respectively, compared with +3.65 D (SD 2.24) and +3.70 D (SD 2.06) after sequential surgery. In all, 29% of triple procedure and 27% sequential surgery eyes had an astigmatic error >or=5.0 D after 1 year (P=0.64), which increased to 34 and 30%, respectively, by the second year. The 5-year graft survival was 85% in both groups. There were no differences in graft survival, visual or refractive outcomes between triple procedure, and sequential surgery techniques. CONCLUSIONS: This analysis provided no evidence of improved visual or refractive outcome after sequential surgery compared with triple procedure.

Efficiency is a legitimate consideration in equitable distribution of cadaveric transplants: development of an efficiency-equality model of equity.

It is proposed that equity is a trade-off, or compromise, between equality and efficiency. The kidney transplant allocation algorithm currently used in the United Kingdom (NAT) was tested in the efficiency-equity model. In an exercise of 2000 past UK donors and a dynamic waiting list of 5000 potential recipients, 4000 transplants were allocated according either by NAT, by equal allocation (EQ) (a lottery), or by efficiency (EF). Diabetic recipients received 7.4% of transplants in NAT, 8.6% in EQ, and 0% in EF; paediatric recipients received 6.8% in NAT, 0.6% in EQ, and 0.7% in EF model. For HLA matching, there were 77.9% favourable or 000 matches in NAT, 3.0% in EQ, and 53.1% in EF. Predicted survival showed better outcomes in EF versus NAT (P < .0001) and in NAT versus EQ (P = .05). The NAT allocation system favours paediatric recipients and does not deny diabetics the chance of a transplant, broadly in line with published public and professional opinions. The NAT scheme achieves better HLA matching than the EF model, and this suggests that the rationale for allocation based primarily on HLA matching could be reexamined.