Since Wilder1 found Toxoplasma-like organisms in many chorioretinal eye lesions at the Armed Forces Institute of Pathology, the significance of toxoplasmosis as a cause of chorioretinitis has assumed major importance. The causative agent of toxoplasmosis (Toxoplasma gondii) is a protozoan which was discovered by Nicolle and Manceaux in 1908.2 The lunate shape of the organism accounts for its name, which is derived from the Greek #####, meaning a bow, or arc. It was first found in the gondi, a small North African rodent used in the laboratory of the Pasteur Institute in Tunis. That this parasite would produce human infections was discovered by Wolf, Cowen, and Paige,* and also by Sabin,5 in 1939.
Cross,6 in a cytologic study of Toxoplasma, showed that in various stages of growth the spherical forms elongate and undergo binary fission and that this always occurs intracellularly. When the host cells are no
CASSADY JV, CULBERTSON CS, BAHLER JW. The Etiology of Retinochoroiditis and UveitisImportance of the Dye (Methylene Blue) Cytoplasm-Modifying Antibody Test for Toxoplasmosis. AMA Arch Ophthalmol. 1955;54(1):28-36. doi:10.1001/archopht.1955.00930020030005