Abstract
Purpose :
To describe the course of inflammatory reactions and elevated intraocular pressure (IOP, a known complication) during episodes of active toxoplasmic retinochoroiditis; and to identify host and disease-related influences on the course of ocular toxoplasmosis (OT).
Methods :
We performed a retrospective, longitudinal study of 210 patients with OT at 7 international sites (North/South America, Europe). Signs of inflammation (anterior chamber [AC] cells and flare; vitreous cells and haze; retinal infiltration), IOP, complications of inflammation, and medications (corticosteroids, antimicrobial agents, glaucoma medications) were collected at every examination during follow-up.
Results :
Data were collected for 293 episodes (1219 visits). Data were available for multiple visits within 252 episodes (181 pts). Median follow-up was 96 days (range, 4-8756 days). Median duration of active toxoplasmic retinochorioiditis was 57 days (95%CI, 50-62 days). There was a strong relationship between duration of active retinal lesions and duration of AC cells (Spearman correlation coefficient [r]=0.33, p=0.002). An increased interval to lesion inactivity was weakly related to primary lesions (vs. recurrences, p=0.049); no relationships were identified with the following factors: patient age, sex, geographic location, lesion size, lesion location (macular, extramacular), or elevated IOP (all p≥0.28). Among patients with AC cells ≥1+ at first visit during an episode (125 episodes, 110 pts), median time to control of anterior segment inflammation (AC cells <1+) was 30 days (95% CI, 24-36 days). Elevated IOP (≥22mmHg) at first visit during an episode occurred in 40 episodes (38 patients). Among these episodes, median time to IOP ≤21mmHg was 20 days (95%CI, 9-31 days). Resolution of elevated IOP did not appear to follow the same time course as change in AC cells; in only 61.8% of episodes had there been a clinically detected decrease in AC cells by the time IOP was controlled. The strong relationship between IOP and AC cells noted at the initial examination of episodes (r=0.33, p<0.0001, n=167) was lost by the first follow-up visit (r=0.15, p=0.060).
Conclusions :
AC cells reflect retinal lesion activity. The reported relationship between IOP and AC cells is probably not causal. A better understanding of intraocular inflammation associated with OT may provide insight into disease mechanisms and help to plan rational treatments.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.