Equine keratomycosis due to Aspergillus flavus in Argentina

Abstract

A 9-year-old gelding presented a corneal ulcer unresponsive to treatment in his right eye. The trauma was caused by vegetal material. The ophthalmologic exam revealed paraxial corneal opacity, whitish discharge, peripheral oedema, congestion of conjunctival vessels and corneal angiogenesis. Microscopic examination of smears revealed the presence of neutrophils and fungal hyphae. On day 3 of culture, several small white fluffy colonies that rapidly turned to pale green were detected. These colonies were isolated to study their micro and macromorphology. Microscopic examination revealed the presence of colourless, thick-walled, roughened conidiophores, ranging from 340 to 1650 μm in length, with globose to sub-globose vesicles, ranging from 22 to 48 μm in diameter. Vesicles had one or two series of phialides. Conidia were globose, olive-green with slightly rough, thin walls that ranged from 3 to 7 μm in diameter. Molecular identification was also performed. Both techniques confirmed the presence of Aspergillus flavus complex. Topical treatment with natamycin resulted in healing within 10 days. To our knowledge, this is the first case of equine keratomycosis reported in Argentina.

Keywords

• Equine
• Keratomycosis
• Aspergillus flavus complex
• natamycin