A. Bacterial Keratitis
B. Viral Keratitis
C. Parasitic Keratitis
D. Fungal Keratits
Ans:D. Fungal Keratitis.
Fungal keratitis /Fungal Corneal Ulcer
- Inflammation of the cornea from infection by a fungal organism.
- Cause: Aspergillus species is the most common isolate in fungal keratitis worldwide,followed by Candida species.
- The precipitating event for fungal keratitis is trauma with a vegetable / organic matter.
- A thorn injury, or in agriculture workers, trauma with a wheat plant while cutting the harvest is typical.
- Pathophysiology:The fungus grows slowly in the cornea and proliferates to involve the anterior and posterior stromal layers. The fungus can break through the descemet’s membrane and pass into the anterior chamber. It has also been shown that infection with fungal keratitis (FK) can be more virulent and damaging compared to that of a bacterial origin. Fungal keratitis was shown to be more likely to perforate the cornea than bacterial keratitis
- Blurred vision, a red and painful eye that does not improve when contact lenses are removed, or on antibiotic treatment, increased sensitivity to light (photophobia), and excessive tearing or discharge. The symptoms are markedly less as compared to a similar bacterial ulcer.
Signsthat are specific to fungal keratitis include :
- An infiltrate with feathery margins, elevated edges, rough texture, gray-brown pigmentation, satellite lesions, hypopyon(unsterile and fixed), and endothelial plaque.
- Amphotericin B is the drug of choice to treat patients with fungal keratitis caused by yeasts.
- Natamycin has a broad-spectrum of activity against filamentous organisms.
- Oral fluconazole and ketoconazole are absorbed systemically with good levels in the anterior chamber and the cornea; therefore, they should be considered in the management of deep fungal keratitis.