Abstract
Purpose::
Recent reports from other institutions have suggested an increasing incidence of non-bacterial infectious corneal ulcers. Our objective was to determine if the etiology of infectious ulcers has changed within the past 7 years at the F.I. Proctor Foundation, and between the last 7 years and a previous survey done from 1976-1999.
Methods::
Microbiological records of all corneal ulcers presenting to the Proctor Foundation from 2000-2006 were evaluated. Herpetic ulcers were excluded from the analysis. Trends in the incidence of acanthamoeba and fungal ulcers from 2000-2006 were assessed using linear regression. Comparison of incidences between this period and 1976-1999 were assessed using a t-test. Acanthamoeba comparisons started in 1986, the first year where the organism was isolated at the Proctor Foundation.
Results::
There was a modest and statistically insignificant increase in the number of acanthamoeba isolates from 1986-1999 period to the 2000-2006 period (2.2/year to 2.7/year, P=0.54). However, within the past 7 years acanthamoeba isolates increased from 1.8/year from 2000-2004 to 5/year from 2005-2006 (P=0.02). The incidence of fungal isolates decreased from 1976-1999 period to the 2000-2006 period (3.2/year to 2.4/year, P=0.50). However in 2006 there were 8 isolates, as many as had been found in the previous 5 years (7 of which were Fusarium spp). The total number of isolates from bacteria, fungi, and acanthamoeba identified has increased from 20/year in the 1976-1999 period to 28/year in the 2000-2006 period (P=0.02). The spectrum of bacterial species isolated has changed since 2000.
Conclusions::
There are no clear differences in the incidence of non-bacterial isolates at the F.I. Proctor Foundation Microbiology Laboratory between the 1976-1999 period and the 2000-2006 period. However, there was an increase in both acanthamoeba and fungal isolates in the past 2 years, indicating the importance of laboratory analysis in clinical care.
Keywords: keratitis • clinical (human) or epidemiologic studies: prevalence/incidence • fungal disease