Donor Blood Type, Leukocyte Testing Can Improve Corneal Graft Outcomes

A retrospective study demonstrates encouraging long-term ocular surface stability rates, rejection rates, and visual acuity outcomes following keratolimbal allograft with HLA/ABO-compatible deceased donor tissue for severe bilateral limbal stem cell deficiency.

Keratolimbal allograft (KLAL) with human leukocyte antigen (HLA) and/or blood type-compatible deceased donor tissue for severe bilateral limbal stem cell deficiency (LSCD) yields encouraging safety and efficacy results, according to a report published in The Ocular Surface.

Researchers conducted a retrospective interventional series of consecutive patients to evaluate safety and efficacy outcomes of KLAL with HLA and/or ABO-compatible deceased donor tissue using oral prednisone, mycophenolate, and tacrolimus in patients with severe bilateral LSCD. If panel reactive antibodies were present, basiliximab was used preoperatively, and if donor-specific anti-HLA antibodies were present, intravenous immunoglobulin (IVIG) was used postoperatively.

The main outcome measures were ocular surface stability, visual acuity, and systemic immunosuppression adverse events. All patients had a minimum follow-up time of 12 months.

A total of 8 eyes of 8 patients (50% women and 50% men; mean age, 48.6±10.1 years [range, 34-65]) were included in the study. The mean follow-up time after KLAL was 37.3±22.7 months (range, 12-71). Half of the patients had combined living-related conjunctival-limbal allograft surgery (LR-CLAL). 

Testing for HLA and blood type compatibility of deceased donors along with tailored use of preoperative basiliximab and postoperative IVIG seems like a promising regimen for patients with advanced bilateral LSCD.

The researchers report all patients had panel reactive antibodies and received basiliximab infusions preoperatively and 5 of 8 patients (63%) had donor-specific anti-HLA antibodies and received IVIG postoperatively. At last follow-up exam, 7 eyes (87.5%) had a stable ocular surface, and 1 eye (12.5%) had failure and keratoprosthesis implantation. They observed a significant improvement in visual acuity from 1.65±0.48 logarithm of the minimum angle of resolution (logMAR) preoperatively to 0.68±0.34 logMAR postoperatively (P =.01). 

The team reported that systemic immunosuppression was well tolerated with minimal adverse events: mild diffuse rejection episodes (n=2); development of diabetes mellitus type 2 (n=1); fungal keratitis (n=4); and herpes simplex epithelial keratitis (n=2).

“The long-term ocular surface stability rates, rejection rates and visual acuity outcomes seem comparable to those previously reported for LR-CLAL alone. Therefore, testing for HLA and blood type compatibility of deceased donors along with tailored use of preoperative basiliximab and postoperative IVIG seems like a promising regimen for patients with advanced bilateral LSCD,” according to the report.

Limitations of the study included the retrospective design and small sample size.

References:

Mimouni M, Cole E, Kim SJ, et al. Outcomes of keratolimbal allograft from ABO compatible donors for severe bilateral limbal stem cell deficiency. Ocul Surf. Published online November 9 2022. doi:10.1016/j.jtos.2022.11.002