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Causes of a recalcitrant corneal ulcer

1Dr R P Center of Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India. Corresponding Author : Prof. Namrata Sharma, E-mail: namrata.sharma@gmail.com Received on : 08/10/2016, Revision accepted on : 18/11/2016 Conflict of Interest : None, Financial Disclosure : None © Current Indian Eye Research. A corneal ulcer is defined as loss of surface corneal epithelium along with infiltration into the surrounding and underlying layers. It may be infectious or non infectious. Non infectious causes of corneal ulcer include mechanical trauma, chronic irritation, contact lens induced or nutritional deficiency. The infectious causes include bacteria, fungi, viruses and protozoa. Recalcitrant corneal ulcer refers to a corneal ulcer which does not respond to the conventional treatment (Figure1). Response of a corneal ulcer to treatment is indicated by decrease in size of the epithelial defect or infiltrates. The time frame for resolution differs for various etiologies of a corneal ulcer. In case of a bacterial or viral corneal ulcer, a recalcitrant corneal ulcer is defined as an ulcer showing no signs of improvement in terms of reduction in size of epithelial defect or infiltrates even after 48 hours of initiation of the specific anti microbial treatment. In case of a fungal corneal ulcer, this time period is extended up to 5-6 days. Epidemiology: