Fusarium keratitis in Brazil: genotyping, in vitro susceptibilities, and clinical outcomes

• Main Authors: Oechsler RA, Yamanaka TM, Bispo PJ, Satori JF, Yu MC, Melo AS, Miller D, Hofling-Lima AL
• Format: Article
• Language: English
• Published: Dove Medical Press 2013-08-01
• Series: Clinical Ophthalmology
• Online Access: http://www.dovepress.com/fusarium-keratitis-in-brazil-genotyping-in-vitro-susceptibilities-and--a14199
• ISSN: 1177-5467; 1177-5483

Rafael A Oechsler,1 Tiago M Yamanaka,1 Paulo JM Bispo,1 Juliana Sartori,1 Maria Cecilia Zorat Yu,1 Analy Salles A Melo,2 Darlene Miller,3 Ana Luisa Hofling-Lima1 1Ophthalmology Department, 2Division of Infectious Diseases, Internal Medicine Department, Federal University of S&atilde;o Paulo, S&atilde;o Paulo, Brazil; 3Bascom Palmer Eye Institute, Miller School of Medicine, University of Miami, Miami, FL, USA Background: The purpose of this paper is to describe clinical characteristics and determine correlations between clinical outcomes and antifungal susceptibility among molecularly characterized ocular Fusarium isolates in Brazil. Methods: Forty-one Fusarium isolates obtained from 41 eyes of 41 patients were retrieved from the ophthalmic microbiology laboratory at S&atilde;o Paulo Federal University and grown in pure culture. These isolates were genotyped and antifungal susceptibilities determined for each isolate using a broth microdilution method. The corresponding medical records were reviewed to determine clinical outcomes. Results: The 41 isolates were genotypically classified as Fusarium solani species complex (36 isolates, 88%), Fusarium oxysporum species complex (two isolates, 5%), Fusarium dimerum species complex (one isolate, 2%) and two isolates that did not group into any of the species complexes. Final best corrected visual acuity varied from 20/20 to light perception and was on average 20/800 (logarithm of the minimum angle of resolution (LogMAR) 1.6). A history of trauma was the most common risk factor, being present in 21 patients (51%). Therapeutic penetrating keratoplasty was necessary in 22 patients (54%). Amphotericin B had the lowest minimum inhibitory concentration for 90% of isolates (MIC90) value (2 &micro;g/mL) and voriconazole had the highest (16 &micro;g/mL). There was an association between a higher natamycin MIC and need for therapeutic penetrating keratoplasty (Mann&ndash;Whitney test, P < 0.005). Conclusion: Trauma was the main risk factor, and therapeutic penetrating keratoplasty was necessary in 54% of patients. Amphotericin B had the lowest MIC90 (2 &micro;g/mL) of the three antifungal agents tested. There was an association between higher natamycin MIC levels and corneal perforation, emphasizing the need for antifungal susceptibility testing and tailoring of antifungal strategies. Keywords: keratitis, Fusarium species, genotyping, antifungal, clinical outcome