Serologic evaluation of patients with primary and recurrent ocular toxoplasmosis for evidence of recent infection

PURPOSE: To identify the frequency of recently acquired vs chronic systemic Toxoplasma gondii infections in patients with ocular toxoplasmosis. METHODS: Serum samples from 22 patients with primary ocular toxoplasmosis ( not from scars) and 42 patients with recurrent ocular toxoplasmosis were te sted for the presence of anti-T. gondii IgM, IgG, and IgA antibodies and co mpared with samples from 24 patients with other causes of uveitis, Intraocu lar production of anti-T, gondii IgG and IgA, and the presence of T. gondii DNA was determined in patients and control subjects from whom ocular fluid was available. RESULTS: Serologic evidence of recently acquired infection was found for 11 (50%) of 22 patients with primary ocular toxoplasmosis and for one (2%) of 42 with recurrent ocular toxoplasmosis. In the uveitis control group, anti -T. gondii IgM antibodies could be detected in two (8%) of 24 patients, but anti-T. gondii IgA antibodies were not detectable. Patients with primary o cular toxoplasmosis and serologic markers of recently acquired systemic inf ection were significantly older than those with chronic infection (P = .008 ). Intraocular production of anti-T. gondii IgG was more frequently noted i n patients with recurrent than primary ocular toxoplasmosis (81% vs 41%,, P < .001), but intraocular T. gondii DNA was more frequently found in patien ts with primary ocular toxoplasmosis than in those with recurrent ocular to xoplasmosis (37% vs 4%; P < .01). CONCLUSIONS: Primary ocular toxoplasmosis can be seen in either recently ac quired or chronic T. gondii infection. Patients with ocular disease and rec ently acquired infection were older and more likely to have T. gondii DNA i n intraocular fluids. (Am J Ophthalmol 1999;128:407-412, (C) 1999 by Elsevi er Science Inc. All rights reserved.).