Influence of Drug Therapy on the Risk of Recurrence of Ocular Toxoplasmosis

Background/aims: Retrospective, observational case series with follow-up examination to analyse the influence of drug therapy on ocular toxoplasmosis (OT) in terms of recurrence-risk.

Methods: In this one centre study an existing data set of 84 patients with active OT was used. Drug therapy for 255 active lesions was retrospectively reconstructed. Median recurrence-free survival time was calculated for the different treatment regimes using Kaplan-Meier estimates.

Results: 20 different regimens were used as treatment of OT in the catchment area of the Interdisciplinary Uveitis Center, University of Heidelberg, Germany. Median recurrence-free survival time was significantly lower after using systemic corticosteroid monotherapy (0.9 years; 95% CI 0.5 to 1.3 years) compared with Toxoplasma gondii-specific antibiotic treatment (3.0 years; 95% CI 2.2 to 3.9 years; p<0.001) or compared with no therapy (3.0 years; 95% CI 2.1 to 3.9 years; p=0.006). No difference could be detected when comparing median recurrence-free survival time after using T gondii-specific antibiotics compared with no therapy (p=0.679).

Conclusions: Although our study shows that drug therapy seems to influence the risk of recurrence of OT, there is no consensus regarding the choice of antiparasitic agents for treatment regimens in the catchment area of the Interdisciplinary Uveitis Center, University of Heidelberg. Survey results provide useful information for treating physicians and for clinical investigators interested in therapy.