As a human opportunistic pathogen Fusarium causes a wide spectrum of infections such as onychomycosis and keratomycosis in healthy individuals. Besides ...
Fusarium species associated to onychomycoses in Colombia. Guevara M.1, Muñoz A.1, Amado Y.1, Bocanegra L.1, Sopo L.2, Motta A.3, Cepero de García M.1, Tabima J.1, Adriana B.1, Restrepo S.1, Celis A.1 1Laboratorio
de Micología y Fitopatología Uniandes (LAMFU), Universidad de los Andes., Bogotá, Colombia, 2Laboratorio Especializado de Micología Médica (LEMM), Bogotá, Colombia, 3Universidad El Bosque; Hospital Simón Bolívar., Bogotá, Colombia.
INTRODUCTION
GENOTYPIC IDENTIFICATION
As a human opportunistic pathogen Fusarium causes a wide spectrum of infections such as onychomycosis and keratomycosis in healthy individuals. Besides, it can cause invasive or disseminated infections in immunosuppressed patients. The prevalence of Fusarium spp., in superficial lesions as onychomycosis could reach 6%. Furthermore, in disseminated infections the percentage of mortality caused by this pathogen is around 70% to 100%. These rates have been associated with a remarkable therapeutic failure, which in turn depends on the species of Fusarium that are isolated and the characterization of the intraspecific complex. Therefore, the aim of this study was to characterize isolates of Fusarium spp. from individuals with onychomycosis to determine the presence of complexes within these species.
CLINICAL ISOLATES
ITS1 -5.8s – ITS 2
Positive isolates of Fusarium spp.
LEMM
Samples: nails of patients with onychomycosis. KOH test: Positive. Culture for Fusarium: Positive
Figure 1. Phylogenetic reconstruction from the ITS region (ITS1, 5.8S, ITS2) using Maximum Likelihood and Bayesian inference. Support values are above branches, and represent bootstrap values for ML and posterior probabilities for BI: ML ⁄ BI.
Genotypic identification
Phenotypic characterization
Elongation factor-1 alpha (EF - 1α). I) Single Spore Culture.
I) DNA extraction.
I) Macroscopic characteristics.
I) Amplification and sequencing: ITS1 -5.8s – ITS 2 and Elongation factor-1 alpha (EF - 1α).
II) Microscopic characteristics: carnation leaf agar growth. III) Microscopic characteristics. Sequence analyses and Phylogenetic reconstruction
I) Sequence analyses II) Maximum likelihood (RAxML, 1000 bootstrap) and bayesian inference (MrBayes, 1M MCMC generations).
Phenotypic characterization
Figure 2. Elongation factor 1-alpha phylogenetic reconstruction using Maximum Likelihood and Bayesian inference. Support values are above branches, and represent bootstrap values for ML and posterior probabilities for BI: ML ⁄ BI.
CONCLUSIONS Fusarium species most frequently isolated from patients with onychomycosis, corresponded to Fusarium solani and Fusarium oxysporum. Our results are consistent with previous studies performed in Colombia. The elongation factor-1-alpha has a greater phylogenetic resolution power compared with the ITS region for the grouping of the Fusarium species. Fusarium oxysporum
Fusarium solani
Fusarium solani and Fusarium oxysporum were the main species identified by phenotypic traits.
It is necessary to include other molecular markers to ensure the delimitation of the different species within the genus Fusarium complexes .
Acknowledgements This study was supported by the Departamento Administrativo de Ciencia, Tecnología e innovación COLCIENCIAS and the Faculty of Sciences, Universidad de los Andes
