Microbial Keratitis After Penetrating Keratoplasty
Infectious keratitis after penetrating keratoplasty leads to a high graft failure rate regardless of the original indication or offending pathogen.
In a recent study by Sun et al, published in Am J Ophthalmol 2017; 178:150–156. Q 2017 Published by Elsevier Inc., the incidence, microbiological profile, graft survival, and determining factors of microbial keratitis after penetrating keratoplasty (PK) were evaluated. It was an observational case series, conducted in 51 patients (52 eyes) during a 10-year period. Medical records of all patients diagnosed with microbial keratitis after penetrating keratoplasty were reviewed.
The study showed that 32 infectious episodes (47.8%) in the first year post-PK and 35 episodes (52.2%) after the first year post-PK. Forty-four gram- positive bacterial isolates (57.9%), 17 gram-negative bacterial isolates (22.4%), and 15 fungal isolates (19.7%) were found. Only, 34.3% grafts remained clear after the infection episode. There was no difference in graft survival rate regarding the original indication of PK or offending pathogen. Use of anti-glaucoma agents was associated with increased risk of graft failure. This concluded that Infectious keratitis after penetrating keratoplasty leads to a high graft failure rate.