Abstract
Purpose: :
To evaluate the effect in inducing polyclonal immunity in patients with Toxoplasma retinochoroiditis after one year.
Methods: :
Randomized, double - blind, clinical trial. Sixteen patients with established diagnosis, through fundus examination, of recurrent Toxoplasma retinochoroiditis were selected from the Uveitis sector - University of São Paulo. Patients under 18 years old, immune compromised, pregnant, with active ocular toxoplasmosis, allergic to any of the substances used on the immune stimulant or with past diagnosis of any other infectious disease (such as syphilis or tuberculosis) were excluded from the study. All patients received, after signing a free and clarified consent term, one subcutaneous injection. Four of these injections contained placebo and twelve contained an immune stimulant. Randomization determined whom received placebo and only the laboratory knew the components of each injection. Five substances that induce polyclonal immunity formed the immune stimulant. All patients had their cellular and humoral immunity checked by specific tests. A follow-up of 1 year was performed to check recurrence with fundus examination on the 1st, 30th, 90th, 120th, 180th, 240th and 360th day after the injection or immediately in case of an episode of low visual acuity.
Results: :
The patients were followed from April/2010 to October/2011. Out of the sixteen patients studied there were 9 (56,25%) men and 7 (43,75%) women. The range of age went from 24 to 69 years old (mean of 36 years old). Ten patients (62,5%) had previous episodes of bilateral retinochoroiditis. Considering the amount of recurrences, 9 patients had two previous episodes and 7 had three previous episodes. Three of the sixteen patients (18,75%) presented recurrence of ocular toxoplasmosis but only one had received placebo.
Conclusions: :
Toxoplasmosis infection accounts for up to 50% of all cases of posterior uveitis worldwide and can affect immune competent and immune compromised patients. Retinochoroiditis can lead to severe visual impairment and is a main concern in endemic countries. It is well known that cellular and humoral immunity are important to prevent future episodes. This study aimed to induce immunity in patients against the Toxoplasma gondii by providing a polyvalent immune stimulant. The majority of the patients did not present recurrence of ocular toxoplasmosis during the follow-up.
Clinical Trial: :
http://www.unifesp.br/reitoria/orgaos/comites/etica/, 1390/05
Keywords: toxoplasmosis • immunomodulation/immunoregulation • uvea