Infectious crystalline keratitis induced by Citrobacter

Background: Microbial keratitis is an important cause of ocular morbidity, with emerging organisms and drug resistance posing a real threat to vision of patients. Case presentation: A 30-year-old female presented with infective keratitis in the left eye. She had been using rose nectar as home remedy for her ailment. With no improvement in her symptoms, she presented to the eye emergency department, where she was started on empirical therapy with moxifloxacin, which was shifted to levofloxacin eye drops after the antimicrobial susceptibility test results came in. Microbiological examination revealed infection with rare gram-negative bacilli Citrobacter koseri. The patient responded well to the treatment with 1.5% levofloxacin eye drops and her vision improved from 20/120 to 20/30 over a course of 3 months. Conclusion: Treatment of microbial keratitis with those antibiotics that the organism is most sensitive to is of paramount importance today, where we often find patients on a cocktail of eye drops, which leads to further resistance and vision deterioration. Culturing of cornea scrapings and antimicrobial susceptibility testing of the isolated organism is now the standard guideline to be followed in the investigation of microbial keratitis.