A patient presents with right eye pain and redness. The slit lamp examination shows leukocytes in the anterior chamber. What is the most likely diagnosis?

In this scenario, the combination of right eye pain, redness, and the presence of leukocytes in the anterior chamber strongly suggests the diagnosis of anterior uveitis. Anterior uveitis, also known as iritis, involves inflammation of the uveal tract, specifically the iris and the anterior portion of the ciliary body.

Leukocytes in the anterior chamber, often referred to as "hypopyon" when there is a significant accumulation, indicate an inflammatory response within the eye. This is characteristic of uveitis, where the inflammation can be seen as cells floating in the aqueous humor during a slit lamp examination.

Symptoms such as eye pain and redness are common in anterior uveitis, often accompanied by photophobia and blurred vision. The acute nature of the presentation aligns with typical cases of anterior uveitis. In contrast, other conditions such as glaucoma might present with elevated intraocular pressure and changes in vision but do not typically show leukocytes in the anterior chamber.

Conjunctivitis would typically lead to a conjunctival injection and discharge rather than intraocular inflammation, and cataracts mainly present with vision changes without associated pain or anterior chamber inflammation. Thus, the characteristics observed in the slit lamp examination distinctly point towards anterior u