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Published on: May 12, 2020
The first case of keratitis caused by Nocardia exalbida
Atsushi Mizota1, Kyoko Haki, Chikako Shiina
1Department of Ophthalmology, Juntendo University Urayasu Hospital, 2-1-1 Tomioka, Urayasu, Japan. mizota@juntendo-urayasu.jp
Background:
Nocardia exalbida was first reported in 2006. We describe a first case of keratitis caused by Nocardia exalbida.
Methods:
Case report
Results:
A patient presented after two weeks of unsuccessful treatment of a corneal ulcer in her right eye. Nocardia keratitis was diagnosed from her culture results, and the species Nocardia exalbida was determined by phylogenetic studies using gene sequence analysis of 16S RNA. The disk diffusion method showed that this Norcardia sp. was sensitive to many antibiotics. Initially, the patient was treated with topical and systemic antibiotics, and corneal epithelium quickly regenerated. But when corticosteroid eyedrops were added, there was a recurrence of the keratitis. Corticosteroids were stopped, and systemic trimethoprim-sulfamethoxazole and topical tobramycin, colistin, chloramphenicol and sulfisoxazole were given. Within one month the corneal ulcer and infiltration disappeared.
Conclusion:
This is the first report of keratitis caused by Nocardia exalbida. This species is susceptible to many antibiotics in vitro and clinically. However, supplementation with corticosteroids can lead to recurrence, and care should be taken when corticosteroids are being considered.