Abstract
Purpose: :
The most recent United States population-based study of the incidence of ulcerative keratitis estimated an incidence of 27.6 cases per 100,000 person-years in Northern California. However, this study, as well as other previous studies, does not accurately represent the uninsured population. Because all uninsured eye care patients in San Francisco, California are routinely referred to the San Francisco General Hospital (SFGH) for treatment, we were able to determine the incidence of ulcerative keratitis in this population, with a secondary analysis of common risk factors and outcomes.
Methods: :
Medical records of all patients seen in the Department of Ophthalmology, SFGH from July 1, 2009 to June 30, 2010 with an ICD-9 code of 371.89 (the code used for all corneal disorders) and an uninsured payor code were reviewed. Cases of ulcerative keratitis were identified along with risk factors and outcomes. Incidence calculations were performed using the estimate of 82,000 uninsured adults living in San Francisco (based on the 2003 California Health Interview Survey (CHIS)).
Results: :
Ten cases of ulcerative keratitis were found out of a total of 158 records, corresponding to an incidence of 12.2 per 100,000 person-years in our study population. Of these patients, 5 (50.0%) wore contact lenses and 1 (10.0%) was HIV-positive. Nine (90.0%) cases were successfully treated with complete eradication of the infection. One (10.0%) patient was lost to follow-up after 3 days of care, last seen with an epithelial defect and an active infiltrate.
Conclusions: :
The unique arrangement of providing all eye care for the medically uninsured in San Francisco in one clinic allowed us to estimate accurately the incidence of ulcerative keratitis in this population, and our study revealed a much lower incidence of ulcerative keratitis in the uninsured population compared to a recent population-based study. This lower incidence may be due to a lower frequency of contact lens use (a known major risk factor) in the uninsured population compared to the insured population.
Keywords: cornea: clinical science • microbial pathogenesis: clinical studies • bacterial disease