Recurrent Fusarium keratomycosis: a light and electron microscopic study

Area of Science:

• Ophthalmology
• Mycology
• Microbiology

Background:

• Fungal keratitis is a serious eye infection.
• Fusarium solani is a common cause of fungal keratitis.
• Penetrating keratoplasty is a surgical option for severe cases.

Observation:

• Corneal buttons from patients with Fusarium solani keratitis were examined using light and electron microscopy.
• Fungal hyphae were observed penetrating Descemet's membrane and posterior stroma.
• Macrophages showed no phagocytic activity against fungal hyphae.

Findings:

• Fungal hyphae remained morphologically intact, suggesting potential viability despite antifungal therapy.
• Penetration of Descemet's membrane by Fusarium solani may render antifungal therapy ineffective.
• Host immune response, specifically macrophage activity, appeared suppressed in affected corneas.

Implications:

• Early diagnosis and treatment of fungal keratitis with antifungal drugs are essential.
• Therapeutic penetrating keratoplasty is most effective when performed before Descemet's membrane is breached.
• Understanding fungal invasion mechanisms and host immune evasion is critical for developing novel therapeutic strategies.