Abstract
Purpose :
To review the incidence, risk factors, and outcomes of bacterial and fungal keratitis after penetrating keratoplasty (PK) and endothelial keratoplasty (EK).
Methods :
The medical records of a large academic private practice in Philadelphia, PA were electronically queried for all cases of confirmed microbial keratitis following PK or EK performed between May 1, 2007 and September 1, 2018. Charts were reviewed to obtain demographic information, past ocular history, details of the microbial keratitis, and graft outcomes. Confirmed microbial keratitis cases were those with either 1) positive cultures for bacteria or fungus; or 2) negative culture results but resolution of an infiltrate after initiation of only topical anti-bacterial or anti-fungal medications. Cases were excluded if infiltrates resolved after the addition of antivirals, even if antivirals were combined with anti-bacterial or anti-fungal agents.
Results :
A total of 2100 transplants (1269 PK and 831 EK) were performed in 1864 eyes of 1601 patients. The average age of patients at first transplant was 63.4 ± 19.9 years, and a higher number of females (860) than males (741) were included (p < 0.05). There were equivalent numbers of right and left eyes performed (50.2% and 49.8% respectively, p = 0.81). Of the 1864 eyes, 200 received multiple transplants (maximum 4). The incidence of microbial keratitis after PK (6.3%) was significantly higher than after EK (2.2%) (p < 0.05). The rate of infection in eyes with two or more prior transplants (9.3%) was significantly higher than in eyes with one prior transplantation (3.1%) (p < 0.05). Infections were due largely to gram positive bacteria (49.0%), followed by gram negative bacteria (26.5%) and fungus (10.2%), while 14.3% of cases had no culture performed or no growth on cultures. Most grafts failed after infectious keratitis (81.6%), and 40.8% required repeat transplantation, keratoprosthesis, or enucleation.
Conclusions :
Microbial keratitis is a relatively common occurrence in patients with prior keratoplasty, and particularly in eyes with prior PK or multiple prior transplants. Infection is an important cause of graft failure and further surgical intervention. To the best of our knowledge, this is the largest review of microbial keratitis in cases of prior PK, and the only review in eyes with prior EK.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.