Infiltrates as factor
Management also will depend on the number of infiltrates.
“In the case of a post DSEK or DMEK infection, if the infection looks like it involves the host stroma, removing the donor graft will not eradicate infection,” he said.
A review of literature on post DSEK and DMEK interface infections shows only a small number of case reports or case series, including a total of 23 patients, Dr. Aldave said.
A small percentage had a positive donor corneal rim culture; 15 were negative. All reported organisms were Candida.
Recipient cultures were performed in 18 of the 23 cases, and all were culture positive.
“The majority of those were Candida, but there were also Staph species and Nocardia. Sometimes, you have to consider a bacterial organism as the cause,” he said.
Among the 23 patients, those treated with topical, intracameral and/or oral antifungal therapy eventually required PK.
However, two patients who received antifungal injections into the interface did not require PK.
In regard to surgical intervention, surgeons can consider removal or exchange of the endothelial graft via a posterior lamellar keratoplasty, but keep in mind that surgical manipulation may allow seeding of the organism into the anterior chamber, Dr. Aldave cautioned.
Additionally, of the four eyes that underwent DSEK graft removal to manage the infection, all eventually required a PK, as did two of the three eyes that underwent DSEK exchange.
As the infection resolved following PK in each of the 10 eyes in which it was performed, Dr. Aldave concluded that a PK appears to be the definitive means to manage an interface keratitis following DSEK.
“If you perform a PK, trephinate a larger diameter than the graft itself so you can excise the host and donor together,” Dr. Aldave said.
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1. Aldave AJ, Dematteo J, Glasser DB, et al. Report of the Eye Bank Association of America Medical Advisory Board Subcommittee on fungal Infection after corneal transplantation. Cornea. 2013; 32:149-154.