All are causes of chronic granulomatous uveitis except –
**Core Concept**
Chronic granulomatous uveitis is a type of ocular inflammation characterized by the presence of granulomas, which are aggregates of immune cells that attempt to wall off and eliminate perceived foreign substances. This condition often results from chronic infections, autoimmune disorders, or systemic diseases that lead to inflammation within the ocular tissues.
**Why the Correct Answer is Right**
Chronic granulomatous uveitis is commonly associated with conditions such as sarcoidosis, tuberculosis, and toxoplasmosis. These diseases trigger a robust immune response, leading to the formation of granulomas in the ocular tissues. The presence of granulomas in the anterior chamber or vitreous humor is a hallmark of chronic granulomatous uveitis. The exact mechanism involves the activation of macrophages and T lymphocytes, which attempt to eliminate the perceived threat, resulting in the formation of granulomas.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it is not a cause of chronic granulomatous uveitis. Instead, it is a type of non-granulomatous uveitis often associated with autoimmune conditions such as rheumatoid arthritis or systemic lupus erythematosus.
**Option B:** Incorrect because it is a common cause of chronic granulomatous uveitis. Sarcoidosis is a systemic disease characterized by the formation of granulomas in various organs, including the eyes.
**Option C:** Incorrect because it is not typically associated with chronic granulomatous uveitis. Fungal endophthalmitis is a type of infectious uveitis that usually presents acutely, rather than chronically.
**Option D:** Incorrect because it is a cause of chronic granulomatous uveitis. Toxoplasmosis is a parasitic infection that can reactivate in the eyes, leading to the formation of granulomas and uveitis.
**Clinical Pearl / High-Yield Fact**
When evaluating a patient with chronic uveitis, it is essential to consider the possibility of systemic diseases such as sarcoidosis, tuberculosis, or toxoplasmosis. A thorough medical history, including travel history and exposure to potential pathogens, can help guide the diagnosis and management of ocular inflammation.
**Correct Answer: A. Non-granulomatous uveitis**