Joint International Conference on Long-term Experiments ...

As in any other cyclic, infectious, self-limiting disease, there can be observed a period
of incubation of 10-21 days, after consumption of infested meat, or even shorter, 5-18
days, after ingestion of oocysts.
The state period comprises the acute infection, which in 80-90% of cases in
asymptomatic. Thus can be explained the determination in populational studies from
many European countries (e.g. France) of an 80% of IgG antitoxoplasma antibodies
possessors, indicators of them having previously acquired the infection.
In 10-20% of cases, even in immunocompetents, the acute infection can manifest
symptomatically, with lymphoganglionic, febrile or mononucleosic syndrome
(adenopathy, fever, asthenia, myalgia, fugitive exanthema, hepatosplenomegaly without
angina, lymphocytosis persistent for days or weeks). During this stage of acute
symptomatic disease, clinical confusions can be made with other diseases that develop
the so-called „mononucleosis-like syndrome” (rubella, HIV infection, Epstein-Barr
infection). Extremely rarely, immunocompetents develop myocarditis, pericarditis,
hepatitis, encephalitis or meningoencephalitis. The presence of acute infection, either
asymptomatic or symptomatic is proven by the IgM antitoxoplasma antibodies.
Chronic (or latent) infection exists in all infested persons after the resolution of
acute phase, for a shorter or longer period of time (weeks-years), sometimes generating
ocular manifestations of recidivating chorioretinitis, at other times chronic toxoplasmic
endometritis. The appearance probability of clinical symptomatology of chronic
infection in immunocompetents is also owing to external or internal factors which
generate a degree of immunodepression. Acutization of chronic infection is marked by
the presence of IgM antitoxoplasma, together with elevated titers of IgG
antitoxoplasma.
The production mechanism of ocular toxoplasmosis in immunocompetents is the
reactivation of congenital infection or acquired acute infection which eventually
cronicizes. The forms of manifestation can be: chorioretinitis or focal necrotic retinitis
(vision disorders, scotomas, local pains, photophobia, epiphora), glaucoma with vision
loss, posterior uveitis or panuveitis, papilitis with optic atrophy.
Endometrial toxoplasmosis resulted after chronicized acute infection, can
generate sterility, abortion, premature birth and infection transmission to the conception
product, resulting in congenital malformations compatible or incompatible with life.
Fig. No.1 – Toxoplasmic Encephalitis Fig. No.2 – Toxoplasmic Chorioretinitis
475