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Over the past four decades, there has been an increase in the percentage of infectious
keratitis caused by fungi (Xie et al., 2001). Infectious keratitis is a potentially sight threatening
condition where delayed or lack of treatment can lead to serious scarring of the cornea,
decreased vision and in some cases the need for corneal transplant (Asgaye and Aimola, 2008). It
has been reported that more than 70 genera of molds and yeast have been associated with
keratitis and other ophthalmic mycoses (Prajna et
al., 2002). Of all possible infections of cornea,
the vast majority is caused by Fusarium spp., Aspergillus spp. (both filamentous fungi) and Candida spp. (a yeast). Proportion of fungal keratitis as causative factor in corneal ulcer varies
from region to region. In India, a favorable tropical environment, coupled with a primarily
agrarian population, is the additional predisposing factor (Anuradha and Kirti, 2005). Fusarium spp., are plant pathogens and soil saprophytes that cause a broad spectrum of infections in
humans, collectively known as fusariosis. Fusarium keratitis is a devastating ocular diseases and
an important cause of morbidity and blindness. Fusarium keratitis remains as a diagnostic
and therapeutic challenge to the ophthalmologist. Difficulties are related to establish a
clinical diagnosis, isolating the etiologic fungal organism in the laboratory, and
treatment. Unfortunately, delayed diagnosis is common, primarily because of lack of suspicion; even
if the diagnosis is made accurately, management remains a challenge because of the poor
corneal penetration and the limited commercial availability of antifungal agents. These infections
are usually very difficult to treat and may result in severe visual loss or even loss of the
eye. Thus the present investigation was carried out to isolate and characterize Fusarium spp., from corneal infections, to evaluate various growth media for the cultivation of Fusarium isolates and to study the growth characteristics of the isolates in various media.
Materials and Methods
Samples were collected from a tertiary eye care hospital in Coimbatore, Tamil Nadu.
Patients with suspected keratitis were included in the present study. The corneal scrapping
was performed aseptically using Kimura's spatula under the magnification of a slit lamp
following the instillation of local anaesthetic eye drop (4% xylocyne) by trained staff, and the
samples were subjected to the standard microbiological procedure like direct microscopic
examination by Gram's staining and potassium hydroxide wet mount (10% KOH) .
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