ABSTRACT
As is true for several laboratory tests, a negative result for antibodies to toxoplasmosis is sometimes more informative than a positive result. All patients with ocular toxoplasmosis should have some evidence for an immune response to toxoplasma. Thus, the absence of antibodies to Toxoplasmosis may exclude the diagnosis of toxoplasmosis. There are 3 caveats to this dictum:
• An absent antibody response could represent a laboratory error. • An immunocompromised patient could have a minimal immune response. • Because the infection may be confined to the eye, the systemic expression of the
immune response could be meager.
