Nocardia asteroides keratitis in south India

Area of Science:

• Ophthalmology
• Microbiology
• Infectious Diseases

Background:

• Nocardia keratitis is a serious ocular infection.
• It is often associated with trauma and can lead to significant vision loss.
• Understanding its epidemiological characteristics is vital for effective management.

Purpose of the Study:

• To identify risk factors, microbiological and clinical features, and epidemiological characteristics of Nocardia keratitis.
• To analyze cases from a tertiary eye care center in South India.

Main Methods:

• A retrospective analysis of 31 patients diagnosed with Nocardia keratitis between September 1999 and September 2001.
• Corneal scrapings were examined using microscopy (10% potassium hydroxide wet mount) and cultured.
• Antibiotic susceptibility testing was performed on isolated Nocardia species.

Main Results:

• Nocardia asteroides accounted for 1.42% of all cultured corneal ulcers (31 out of 2184).
• 10% potassium hydroxide wet mount correctly identified all cases.
• Risk factors included history of ocular trauma (93.55%), particularly with soil and sand (90.32%), and agricultural work (70.97%).
• Most isolates were susceptible to gentamicin (100%) and ciprofloxacin (93.55%).
• Many patients presented late (32.26% between 15-35 days) and had received prior treatments (83.87%), including traditional medicines (48.39%).

Conclusions:

• Nocardia keratitis should be suspected in patients with a history of eye trauma involving soil or sand.
• Early detection and appropriate treatment with topical antibiotics are essential.
• The organism remains sensitive to commonly used ophthalmic antibiotics.