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Risk factors and causative organisms in microbial keratitis
Matthew Green1, Andrew Apel, Fiona Stapleton
1Gold Coast Hospital, Southport, Australia. matdgreen@gmail.com
Cornea
|February 5, 2008
Summary
Contact lens wear is the leading risk factor for microbial keratitis, with Pseudomonas aeruginosa being the most frequently identified causative organism. This study analyzed risk factors, pathogens, and outcomes in Australian patients.
Area of Science:
- Ophthalmology
- Microbiology
- Infectious Diseases
Background:
- Microbial keratitis is a significant cause of vision loss.
- Understanding risk factors and causative organisms is crucial for effective management.
Purpose of the Study:
- To identify risk factors, causative organisms, antibiotic resistance patterns, and clinical outcomes of microbial keratitis.
- To analyze patient demographics and clinical presentations in a tertiary Australian hospital.
Main Methods:
- Retrospective audit of 253 cases of microbial keratitis over 5 years.
- Corneal scrapings analyzed via Gram stain and culture.
- Disease severity index calculated based on epithelial defect, anterior chamber reaction, and lesion location.
Main Results:
- Contact lens wear (22%) was the most common risk factor, followed by ocular surface disease (18%) and trauma (16%).
- Pseudomonas aeruginosa (17%) was the most frequently isolated organism, particularly in contact lens-related cases.
- Antibiotic resistance was low: 2% for ciprofloxacin, 20% for cephalothin (Gram-positive), and none for gentamicin.
Conclusions:
- Contact lens wear is the primary risk factor for microbial keratitis.
- P. aeruginosa is the most common pathogen identified.
- Low antibiotic resistance observed for key agents.
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