Epidemiology and microbiology of microbial keratitis in Queensland, Australia

Aim: Guide practitioners’ management of microbial keratitis (MK) by providing epidemiological information to define the disease and trends of MK in Queensland, Australia. Methods: This project studies MK through two databases to define and analyse the disease in Queensland. Databases used were the Queensland microbial keratitis database (QMKD), which is a multi-centre pathology database of all patients with culture positive MK in Queensland, Australia between 2005-2015; and Princess Alexandra Hospital microbial keratitis audit (PAH MK audit) is an single centre medical record review of patients with culture positive MK between 1999-2015. Results: QMKD included 3182 corneal scrapes which yielded 4111 organisms. Estimated incidence of culture positive microbial keratitis was 0.66 cases per 10 000 people (95% CI 0.65-0.67). Pseudomonas aeruginosa was most common single isolate (729, 17.7%), although gram positive organisms were more common overall (2737, 66.6%). Fungal organisms were cultured in 6% of cases, while acanthamoeba comprised only 1% of records. The yearly incidence of MK in children was estimated to be 0.11 cases per 10 000 people 16 years old or younger (95% CI 0.086-0.134). Cultures positive for Streptococcus pneumoniae (17; 13.6%; p<0.001) and bacteria sensitive to all recorded antibiotics (96.8%; p<0.001) were significantly more common in children. Incidence of protozoal isolation decreased over time (p=0.055). Yeasts showed a linear increase in incidence (p=0.045). PAH MK audit included 895 episodes. Most common: risk factor was contact lens wear (324, 36.2%), isolated organism was Pseudomonas aeruginosa (181, 55.9%) and treatment was monotherapy with a fluoroquinolone (172, 53%). CLMK was most common between 2009-2011 (49.5% vs other years 32%, p<0.001). Poisson regression of the interrupted time series showed there was a significant decrease in the rate over time after 2010 (p<0.001). 328 patients’ records were included in the analysis of steroid treatment of bacterial keratitis. Odds ratio of better outcomes with high dose steroids was 5.49 (CI 1.6-19.0, p=0.007). Conclusion: 1. Estimated incidence of MK was 0.66 cases per 10 000 people, the incidence of MK secondary to protozoa is likely to be decreasing while the incidence of MK culturing yeast is increasing. 2. Rate of CLMK in our community appears to have peaked during 2009-2011 3. High dose steroid treatment is significantly associated with better visual outcomes in this case series

Grantor dc:publisher

UNSW, Sydney

Year dc:date

2020

Author dc:creator

• Green, Matthew

• Keratitis
• Queensland

Statement dc:rights

• open access
• CC BY-NC-ND 3.0
• free_to_read

Licence

• https://purl.org/coar/access_right/c_abf2
• https://creativecommons.org/licenses/by-nc-nd/3.0/au/

Language dc:language

EN

Identifier

https://doi.org/10.26190/unsworks/22335

OAI identifier oai:identifier

oai:unsworks.library.unsw.edu.au:1959.4/70621