Staphylococcus aureus keratitis: a review of hospital cases.
BACKGROUND
Methicillin-resistant Staphylococcus aureus (MRSA) infection is an important public health issue. The study aimed to characterize the patient demographics, clinical features, antibiotic susceptibility, and clinical outcomes of keratitis caused by S. aureus, and to make a comparison between MRSA and methicillin-sensitive S. aureus (MSSA) isolates.


RESULTS
Patients (n = 59) with culture-proven S. aureus keratitis treated in Chang Gung Memorial Hospital between January 1, 2006, and December 31, 2010, were included in our study. Patients' demographic and clinical data were retrospectively reviewed. Twenty-six MRSA (44%) and 33 MSSA (56%) isolates were collected. The MRSA keratitis was significantly more common among the patients with healthcare exposure (P = 0.038), but 46.2% (12/26) of patients with MRSA keratitis were considered to have community-associated infections. All isolates were susceptible to vancomycin. MRSA isolates were significantly more resistant to clindamycin, erythromycin, and sulfamethoxazole/trimethoprim. Ocular surface disease was a significant risk factor for MRSA keratitis (P = 0.011). Visual outcome did not differ significantly between the MRSA and MSSA groups. However, age (B = 0.01, P = 0.035, 95% confidence interval [CI]: 0.001-0.019) and visual acuity at presentation (B = 0.749, P<0.001, 95% CI: 0.573-0.926) were significantly correlated with visual outcome.


CONCLUSIONS
Ocular surface disease is an important predisposing factor for S. aureus keratitis, especially for MRSA infections. Advanced age and poor visual acuity at presentation are important prognostic indicators for poor visual outcome in S. aureus keratitis. Oxacillin resistance may not be a significant prognostic indicator.
Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou, Taiwan.
Sherine Jue
SJ
Ong
Yhu-Chering
YC
Huang
Hsin-Yuan
HY
Tan
David H K
DH
Ma
Hsin-Chiung
HC
Lin
Lung-Kun
LK
Yeh
Phil Y F
PY
Chen
Hung-Chi
HC
Chen
Chih-Chun
CC
Chuang
Chee-Jen
CJ
Chang
Ching-Hsi
CH
Hsiao
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D002981:Clindamycin / Q000627:therapeutic use; D004917:Erythromycin / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007223:Infant; D007634:Keratitis / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D008297:Male; D008712:Methicillin / Q000627:therapeutic use; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects* / Q000502:physiology; D008875:Middle Aged; D010068:Oxacillin / Q000627:therapeutic use; D011379:Prognosis; D013203:Staphylococcal Infections / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D016896:Treatment Outcome; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000627:therapeutic use; D014640:Vancomycin / Q000627:therapeutic use; D014792:Visual Acuity
D000900:Anti-Bacterial Agents; D002981:Clindamycin; D004917:Erythromycin; D014640:Vancomycin; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D008712:Methicillin; D010068:Oxacillin