RESUMO
Sera of 80 cases of chronic tonsillitis and 30 normal controls were examined for Toxoplasma antibodies by the indirect immunofluorescent antibody titer were found to be higher in patients than in the control group. An indirect immunoperoxidase technique was applied to all cases of tonsillitis [seropositive and seronegative] to detect Toxoplasma antigen in the tissues. They were also examined histopathologically [by Hx. and E]. Toxoplasma antigen was detected in 69% of seropositive cases and in only 2% of seronegative cases. All cases with antibody titer of 1/128 or more showed Toxoplasma antigen in their tissues. The histopathological picture of tonsils of positive cases of toxoplasmosis showed the characteristic features of toxoplasmic lymphadenitis. The results of this work showed the usefulness of immunoperoxidase technique as a valuable and reliable test to confirm the diagnosis of serologically and histologically suspicious cases of toxoplasmic lymphadenitis