Atypical Ocular Toxoplasmosis Presenting as Isolated Corneal Ulceration in a 12-Year-Old Female Patient: A Case Report

Toxoplasmosis is a widespread zoonotic infection caused by the obligate intracellular protozoan Toxoplasma gondii. It is estimated that approximately one billion people are infected globally, with the highest prevalence observed in tropical regions. Cats serve as the definitive hosts, and humans typically acquire the infection through direct or indirect contact with feline feces or by consuming undercooked meat. In the vast majority of cases, ocular toxoplasmosis presents as a distinct focal retinochoroiditis, frequently adjacent to an old retinochoroidal scar, accompanied by a moderate to severe vitreous reaction. However, atypical forms can mimic other ocular diseases, which often causes misdiagnosis, delayed appropriate treatment, and a subsequently worsened visual prognosis. Isolated involvement of the anterior segment, specifically presenting as corneal ulceration, represents an exceptionally rare clinical entity. The purpose of this case report is to highlight a comprehensive diagnostic and therapeutic approach to an atypical presentation of acute toxoplasmosis keratitis with ulceration using a modern targeted antiparasitic regimen.