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Microbial Keratitis After Penetrating Keratoplasty
Jen-Pin Sun1, Wei-Li Chen2, Jehn-Yu Huang1
1Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan.
Purpose:
To report the incidence, microbiological profile, graft survival, and determining factors of microbial keratitis after penetrating keratoplasty (PK).
Design:
Observational case series.
Methods:
The study involved 51 patients (52 eyes) who were treated at a single tertiary referral center during a 10-year period. Retrospective chart review included medical records of all patients diagnosed with microbial keratitis after penetrating keratoplasty at the National Taiwan University Hospital between January 2000 and December 2009. The main outcome measures were incidence of graft infection, microbial profile, and graft survival status.
Results:
There were 871 PKs performed and 67 episodes in 52 eyes of culture-positive microbial keratitis during the study period. There were 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. Twenty-three (34.3%) grafts remained clear after the infection episode with a mean follow-up of 1127 days (range, 25-3962 days). There was no difference in graft survival rate regarding the original indication of PK or offending pathogen. Suture-related infection was associated with decreased risk of graft failure (P = .02), while the factor associated with increased risk of graft failure was usage of antiglaucoma agents (P = .01).
Conclusion:
Infectious keratitis after penetrating keratoplasty leads to a high graft failure rate. Such complications can occur before or after the first year post-PK.
Insights
Microbial keratitis following penetrating keratoplasty (PK) is common, with infections occurring both within and after the first year post-surgery. This complication significantly impacts graft survival rates.
Area of Science:
- Ophthalmology
- Infectious Diseases
- Transplantation Surgery
Background:
- Corneal transplantation, or penetrating keratoplasty (PK), is a common procedure to restore vision.
- Infectious keratitis is a serious complication that can lead to graft failure after PK.
- Understanding the incidence and risk factors of microbial keratitis post-PK is crucial for improving patient outcomes.
Purpose of the Study:
- To determine the incidence and microbiological characteristics of microbial keratitis after PK.
- To evaluate graft survival rates and identify factors influencing graft failure post-PK.
- To analyze the timing of infectious keratitis episodes relative to PK.
Main Methods:
- A retrospective observational case series was conducted.
- Medical records of 51 patients (52 eyes) who developed microbial keratitis after PK between 2000 and 2009 were reviewed.
- Data collected included incidence, causative microorganisms, graft survival, and associated risk factors.
Main Results:
- 67 episodes of culture-positive microbial keratitis occurred in 52 eyes following 871 PKs.
- Infections were observed both within the first year (47.8%) and after the first year (52.2%) post-PK.
- Gram-positive bacteria were the most common isolates (57.9%), followed by gram-negative bacteria (22.4%) and fungi (19.7%). Graft survival was 34.3%. Suture-related infections decreased graft failure risk (P=.02), while antiglaucoma agent use increased it (P=.01).
Conclusions:
- Microbial keratitis post-PK is associated with a high rate of graft failure.
- Infections can manifest at any time after PK, including beyond the first year.
- Identifying and managing risk factors, such as antiglaucoma agent use, is essential for preserving graft integrity.
