| Toxoplasmic chorioretinitis | |
|---|---|
| Other names | Ocular toxoplasmosis |
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| Chorioretinal scar in the macula of an inactive congenital toxoplasmosa infection | |
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| The typical “headlight-in-fog" appearance caused by vitreous inflammation in toxoplasmosis | |
| Specialty | Infectious diseases, ophthalmology  |
| Causes | Toxoplasma gondii |
Toxoplasma chorioretinitis, more simply known as ocular toxoplasmosis, is possibly the most common cause of infections in the back of the eye (posterior segment) worldwide. The causitive agent is Toxoplasma gondii, and in the United States, most cases are acquired congenitally. The most common symptom is decreased visual acuity in one eye. The diagnosis is made by examination of the eye, using ophthalmoscopy. Sometimes serologic testing is used to rule out the disease, but due to high rates of false positives, serologies are not diagnostic of toxoplasmic retinitis.
If vision is not compromised, treatment may not be necessary. When vision is affected or threatened, treatment consists of pyrimethamine, sulfadiazine, and folinic acid for 4–6 weeks. Prednisone is sometimes used to decrease inflammation.