Differential Diagnosis for Unilateral Conjunctivitis
Single Most Likely Diagnosis
- Allergic conjunctivitis: This is the most likely diagnosis given the unilateral presentation during spring, which is a common time for allergic reactions due to pollen. The patient's age and the sudden onset also support this diagnosis.
Other Likely Diagnoses
- Viral conjunctivitis: This is a common cause of conjunctivitis, especially in adults, and can present unilaterally. The sudden onset and the fact that it's occurring during a time of increased viral activity (e.g., spring) make it a plausible option.
- Bacterial conjunctivitis: Although less common in adults, bacterial conjunctivitis can occur, especially if there's a history of trauma, contact lens use, or other predisposing factors. The unilateral presentation and acute onset are consistent with this diagnosis.
Do Not Miss Diagnoses
- Acute angle-closure glaucoma: This is a medical emergency that can present with unilateral conjunctivitis, severe eye pain, and vision loss. It's crucial to rule out this condition due to its potential for permanent vision loss if not promptly treated.
- Herpes zoster ophthalmicus: This condition can cause unilateral conjunctivitis, along with a painful rash on the face. Given the patient's age, this is a critical diagnosis to consider, as it can lead to serious complications if not treated promptly.
Rare Diagnoses
- Giant papillary conjunctivitis: This condition is associated with contact lens use and can cause unilateral conjunctivitis. However, given the patient's age and the lack of information about contact lens use, this is a less likely diagnosis.
- Parasitic conjunctivitis: This is a rare cause of conjunctivitis, often associated with travel or exposure to certain animals. The presentation can be unilateral, but it's less likely given the context provided.