Ocular toxoplasmosis: patient age and other risk factors for a severe course of disease

Purpose Atypical disease courses of ocular toxoplasmosis (OT) have been reported in elderly patients. The aim of this study was to determine whether patient age is correlated with relevant clinical parameters. Methods A retrospective clinical study and statistical analysis was conducted on patients (n=180) with active OT. Results The age of first disease manifestation showed a clear unimodal distribution with a median incidence peak at age 26 while recurrences did not follow an age specific pattern (median= 35 years). First manifestation of OT or recurrence occurring after the age of 35 are associated with larger lesion size (2‐3 PD; contingency coefficient [CC]=0.304; p=0.047; n=60) and (CC=0.32; p=0.009) respectively. Additionally, older patients displayed uveitis anterior (63.2%; p=0.055; n=56) and vitreous involvement (89.5%; p=0.054; n=78) more frequently. Complications during OT (secondary IOP, macula and peripapillary edema, ablatio) did not correlate with patient age, but were attributable to localisation of lesions (central= 29.2% vs. peripheral=9%; p=0.039). Recurrences were present in 70% of patients (47.9%:1‐3 episodes vs. 21.8%:4‐7 episodes), whereas bi‐ocular OT always predisposes for recurrences. Standard therapy consisted of clindamycin. Large OT lesions more frequently required systemic steroid treatment (72.9% in 2‐3 PD cases vs. 48.3% in 1 PD cases; CC=0.271; p=0.007; n=124). Conclusion Patient age was significantly correlated with lesion size and inflammatory involvement of the anterior part of the eye. Localisation of lesions is a predictor for complications.