Abstract
Purpose :
Infectious microbial keratitis is a sight threatening ophthalmic condition. The use of contact lens (CL) is a well-established risk factor and significantly increases the rate of microbial keratitis. However, the differences in demographic pattern, clinical characteristics and susceptibility patterns are not well-understood in an Asian population. In this study, the authors investigate the differences in infectious keratitis between CL wearers and non-wearers in a tertiary hospital.
Methods :
This was a retrospective review of all patients with culture-positive corneal scrapings performed for infectious keratitis at National University Hospital, Singapore, between April 01, 2012 and October 31, 2016. Relevant patient demographics, clinical parameters and treatment outcomes were collated on a standardized data collection form. Comparison was made between CL wearers and non-wearers.
Results :
A total of 219 unique patients were included in this study, 148 (67.6%) of whom were CL-related keratitis. CL wearers were significantly younger (24.1±10.6 years old vs 44.8±20.0 years old, p<0.01), more likely to be female (68.9% vs 25.4%, p<0.01). On the other hand, non-CL wearers were significantly more likely to have had preceding ocular trauma (5.6% vs 0.7%, p<0.01), had pre-existing ocular pathology (26.8% vs 1.4%, p<0.01), or received prior treatment with ocular steroids (15.5% vs 1.4%, p<0.01). There was no difference in race or laterality between the two groups (p>0.05 for all). Pseudomonas aeruginosa was the commonest organism isolated (53.9% of all), and was significantly more common in contact-lens wearers than non-wearers (69.6% vs 21.1%, p<0.01). The presenting visual acuity and intraocular pressure (IOP) were both significantly worse in the non-CL wearer group (median LogMAR [IQR]: CL wearers, 0.30 [0.18, 0.70]; non-CL wearers, 0.78 [0.18, 2.90]; IOP in mmHg [IQR]: CL wearers, 14.0 (12.0, 16.0); non-CL wearers, 16.0 (13.0, 20.0); both p<0.01).
Conclusions :
Patients with CL-related microbial keratitis were significantly younger, more likely to be female, and have Pseudomonas aeruginosa as the offending organism, while non-CL related microbial keratitis tended to present later and with worse clinical presentation. A higher index of suspicion should be advocated in non-CL wearers presenting with blurred vision and red eye.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.