LAUSR

PURPOSE To investigate the demographics, risk factors, microbiology and resistance pattern at a tertiary hospital and to detect the shifting trend over two decades. DESIGN A retrospective observational case series. METHODS We reviewed all records of patients with microbial keratitis (MK) that were hospitalized in National Taiwan University Hospital between 2007 and 2016. Demographics, predisposing factors, pathogens, and clinical courses were compared to our previous study conducted from 1992 to 2001. Antibiotic susceptibility was compared with those conducted from 1994 to 2005. RESULTS The percentage of patient 60 years and older in MK population was increasing (P =2.1E-21). The proportion of trauma-related MK declined while MK related to chronic ocular or systemic disorders rose. The prevalence of nontuberculous mycobacteria (NTM) showed a decreasing trend (P =0.0032) while Microsporidia has been increasingly detected. The two most common bacterial isolates were Pseudomonas aeruginosa (35.2%) and Staphylococcus species (13.2%). Managements of these infection did not differ in common pathogens between the two decades. The susceptibility of Staphylococcus species to oxacillin reduced significantly (P =0.002) and there was an increase in Methicillin-resistant Staphylococcus aureus keratitis. CONCLUSIONS Contact lens wear remained the most common predisposing factor with Pseudomonas species as the major pathogen. However, chronic disorder-related microbial keratitis was on the rise along with an increasing trend of oxacillin-resistance in Staphylococcus species. We found a decreasing trend in NTM keratitis while Microsporidia keratitis was considered as emerging ocular diseases. Though Gram-negative isolates remained susceptible to all antibiotics tested, antibiotic resistance was more common in Gram-positive isolates.