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Fungal keratitis is a common but severe eye infection in tropical and subtropical areas of the world. In regions with a temperate climate, the frequency of infection is rising in patients with contact lenses and following trauma. Early and adequate therapy is important to prevent disease progression and loss of vision. The management of Fusarium keratitis is complex, and the optimal treatment is not well defined. We investigated the in vitro activity of chlorhexidine and seven antifungal agents against a well-characterized collection of Fusarium isolates recovered from patients with Fusarium keratitis. The fungus culture collection of the Center of Expertise in Mycology Radboudumc/CWZ was searched for Fusarium isolates that were cultured from cornea scrapings, ocular biopsy specimens, eye swabs, and contact lens fluid containers from patients with suspected keratitis. The Fusarium isolates that were cultured from patients with confirmed keratitis were all identified using conventional and molecular techniques. Antifungal susceptibility testing was performed according to the EUCAST broth microdilution reference method. The antifungal agents tested included amphotericin B, voriconazole, posaconazole, miconazole, natamycin, 5-fluorocytosine, and caspofungin. In addition, the activity of chlorhexidine was determined. The fungal culture collection contained 98 Fusarium isolates of confirmed fungal keratitis cases from 83 Dutch patients and 15 Tanzanian patients. The isolates were collected between 2007 and 2017. Fusarium oxysporum ( n  = 24, 24.5%) was the most frequently isolated species followed by Fusarium solani sensu stricto ( n  = 18, 18.4%) and Fusarium petroliphilum ( n  = 11, 11.2%). Amphotericin B showed the most favorable in vitro inhibition of Fusarium species followed by natamycin, voriconazole, and chlorhexidine, while 5-fluorocytosine, posaconazole, miconazole, and caspofungin showed no relevant inhibiting effect. However, chlorhexidine showed fungicidal activity against 90% of F. oxysporum strains and 100% of the F. solani strains. Our study supports the clinical efficacy of chlorhexidine and therefore warrants its further clinical evaluation for primary therapy of fungal keratitis, particularly in low and middle income countries where fungal keratitis is much more frequent and, currently, antifungal eye drops are often unavailable., (Copyright © 2019 Oliveira dos Santos et al.)

Multiresistant Shigella flexneri isolates were cultured from the cornea and stool of a girl. Genetic analysis showed the isolates were identical. Shigella spp. are rare causes of ulcerative keratitis; there have only been 14 published cases since 1943. Although prognosis after local treatment is good, shigellosis is a systemic infection, possibly leading to dehydration.

Keratitis due to Nocardia farcinica occurred in a 49-year-old female after inappropriate cleaning of her semipermeable rigid contact lenses with basin-stored water during a holiday in France. N. farcinica was differentiated from Nocardia asteroides by its growth at 45 degrees C, acid production from rhamnose, its opacification of Middlebrook 7H10 agar, and its marked degree of resistance to all cephalosporins, aminoglycosides, tetracyclins, macrolides, and trimethoprim-sulfamethoxazole. To the best of our knowledge, this is the first reported case of human N. farcinica keratitis, confirming that this microorganism can be responsible for serious human disease.