Ocular toxoplasmosis and toxocariasis in childhood

Toxoplasmosis and toxocariasis are parasitic infections that are transmitted by cats and dogs, respectively, to humans, and which may induce posterior uveitis already in childhood. Toxoplasmosis presents as a congenitally or postnatally contracted infection whereas toxocariasis is always an acquired disease. The typical ocular sign of toxoplasmosis is retinochoroiditis, occurring as an active lesion, in most instances, associated with an inactive pigmented scar. In contrast, toxocariasis leads to a choroidal granuloma secondarily involving the retina or an endophthalmitis-like picture. Although toxoplasmosis represents the most common cause of posterior uveitis, there are uncertainties regarding the timing and specificity of the diagnosis, namely in atypical cases and those at risk of permanent severe loss of function. Antiparasitic treatment should be tailored to the severity of the inflammation and the risk of visual function loss. Concomitant steroids may be used to control the sequelae of unspecific inflammation, but should be used with caution and must be combined with an antimicrobial regimen. Because it is a rare disorder, one may not be familiar with the clinical presentation and suggested therapy for ocular toxocariasis. With this survey we, therefore, wish to provide a current, practice-oriented overview on the infection, ocular manifestations, diagnosis and treatment of ocular toxoplasmosis and toxocariasis in childhood.