Differential Diagnosis for Blurred Vision and Eye Pain in a Middle-Aged Man with Recent Tuberculosis Diagnosis
Single Most Likely Diagnosis
- A. Ethambutol: This is the most likely cause of the patient's symptoms. Ethambutol is a first-line antitubercular medication known to cause optic neuritis, which can lead to blurred vision and eye pain. The risk of this side effect is dose-dependent and more common at higher doses.
Other Likely Diagnes
- B. Isoniazid: While less commonly associated with eye symptoms compared to ethambutol, isoniazid can cause peripheral neuropathy and, in rare cases, optic neuritis. However, the symptoms described are less typical for isoniazid toxicity.
- C. Pyrazinamide: This medication is not commonly associated with eye symptoms or blurred vision directly. Its side effects more often include hepatotoxicity and arthralgias.
Do Not Miss Diagnoses
- Rifampin-induced uveitis: Although rare, rifampin can cause uveitis, which might present with eye pain and blurred vision. Missing this diagnosis could lead to severe complications, including vision loss if not promptly treated.
- Tubercular meningitis or central nervous system tuberculosis: While not directly related to the medications, it's crucial to consider the possibility of CNS involvement by tuberculosis itself, especially if the patient has been recently diagnosed and started on treatment. CNS tuberculosis can cause a variety of symptoms, including vision changes.
Rare Diagnoses
- Other drug-induced causes: Other medications the patient might be taking, not listed here, could potentially cause eye symptoms. However, given the context of recent tuberculosis diagnosis and treatment initiation, these are less likely.
- Direct tubercular infection of the eye: Tuberculosis can rarely infect the eye directly, causing symptoms like blurred vision and pain. This would be an unusual presentation but should be considered in the differential diagnosis, especially in endemic areas or in patients with advanced disease.