Session Type: ePosters
Session Title: ePosters
Authors(s): A. Manzanal, A. Sorarrain, M. Alonso, M. Ercibengoa, G. Cilla, M. Alkorta
Authors Affiliations(s): Biodonostia, Infectious Diseases Area, Respiratory Infection and Antimicrobial Resistance Group; Osakidetza Basque Health Service, Donostialdea Integrated Health Organisation, Microbiology Department, 20014 San Sebastian, Spain., Spain
Background:
The aim of this work was to compare three different protocols and to analyze how many replications were required for correct fungal identification by MALDI-TOF MS.
Methods:25 fungal samples from patients with onychomycosis were analyzed. The distribution was as follows: 24 dermatophytes (Trichophyton rubrum, n=16), (Trichophyton interdigitale; n=3), (Trichophyton mucoides, n=2), (Trichophyton mentagrophytes, n=3) and a filamentous fungi (Fusarium oxysorum). The identification obtained with MALDI-TOF MS was compared with the identification by a traditional method under a microscope with lactofenol-blue stain or/and using a molecular method: amplification and subsequent sequencing of the ITS gene. The three protocols applied in this study were described as: one) The colony was displayed on the spot of the MALDI-TOF target, then the 2 µL of matrix (α-Cyano-4-hydroxycinnamic; two) the colony was displayed on the spot of MALDI-TOF target and 2 µl of formic acid, ending with the matrix (the same as in protocol one); three) firstly 2 µL /well of 100% formic acid was displayed on the MALDI-TOF MS without allowing it to dry, the colony was added, and finally, 2 µL of matrix (α-Cyano-4-hydroxycinnamic acid) were added and mixed, the plate was dried and the results were obtained via MALDI-TOF MS.
Results:Protocols 1 and 2 correctly identified 52% (13/25 in both cases) of the samples in comparison to the reference methods. Despite the lack of difference between protocols 1 and 2, there was a statistically significant difference with protocol 3, which was able to identify 92% of the samples (p=0.004586).
For a correct identification at species level, 1 to 12 replications were needed with a median of six replications .
According to our results, due to the absence of standardization, the identification of dermatophytes by MALDI-TOF MS is in a preliminary stage of development. Results of protocol three were promising, but they should be verified in a larger and more diverse group of samples.
Keyword(s): dermatophytes, filamentous fungi, MALDITOF MSCOI Other: The authors declare no conflict of interests
Session Type: ePosters
Session Title: ePosters
Authors(s): A. Manzanal, A. Sorarrain, M. Alonso, M. Ercibengoa, G. Cilla, M. Alkorta
Authors Affiliations(s): Biodonostia, Infectious Diseases Area, Respiratory Infection and Antimicrobial Resistance Group; Osakidetza Basque Health Service, Donostialdea Integrated Health Organisation, Microbiology Department, 20014 San Sebastian, Spain., Spain
Background:
The aim of this work was to compare three different protocols and to analyze how many replications were required for correct fungal identification by MALDI-TOF MS.
Methods:25 fungal samples from patients with onychomycosis were analyzed. The distribution was as follows: 24 dermatophytes (Trichophyton rubrum, n=16), (Trichophyton interdigitale; n=3), (Trichophyton mucoides, n=2), (Trichophyton mentagrophytes, n=3) and a filamentous fungi (Fusarium oxysorum). The identification obtained with MALDI-TOF MS was compared with the identification by a traditional method under a microscope with lactofenol-blue stain or/and using a molecular method: amplification and subsequent sequencing of the ITS gene. The three protocols applied in this study were described as: one) The colony was displayed on the spot of the MALDI-TOF target, then the 2 µL of matrix (α-Cyano-4-hydroxycinnamic; two) the colony was displayed on the spot of MALDI-TOF target and 2 µl of formic acid, ending with the matrix (the same as in protocol one); three) firstly 2 µL /well of 100% formic acid was displayed on the MALDI-TOF MS without allowing it to dry, the colony was added, and finally, 2 µL of matrix (α-Cyano-4-hydroxycinnamic acid) were added and mixed, the plate was dried and the results were obtained via MALDI-TOF MS.
Results:Protocols 1 and 2 correctly identified 52% (13/25 in both cases) of the samples in comparison to the reference methods. Despite the lack of difference between protocols 1 and 2, there was a statistically significant difference with protocol 3, which was able to identify 92% of the samples (p=0.004586).
For a correct identification at species level, 1 to 12 replications were needed with a median of six replications .
According to our results, due to the absence of standardization, the identification of dermatophytes by MALDI-TOF MS is in a preliminary stage of development. Results of protocol three were promising, but they should be verified in a larger and more diverse group of samples.
Keyword(s): dermatophytes, filamentous fungi, MALDITOF MSCOI Other: The authors declare no conflict of interests
Session Type: ePosters
Session Title: ePosters
Authors(s): A. Manzanal, A. Sorarrain, M. Alonso, M. Ercibengoa, G. Cilla, M. Alkorta
Authors Affiliations(s): Biodonostia, Infectious Diseases Area, Respiratory Infection and Antimicrobial Resistance Group; Osakidetza Basque Health Service, Donostialdea Integrated Health Organisation, Microbiology Department, 20014 San Sebastian, Spain., Spain
Background:
The aim of this work was to compare three different protocols and to analyze how many replications were required for correct fungal identification by MALDI-TOF MS.
Methods:25 fungal samples from patients with onychomycosis were analyzed. The distribution was as follows: 24 dermatophytes (Trichophyton rubrum, n=16), (Trichophyton interdigitale; n=3), (Trichophyton mucoides, n=2), (Trichophyton mentagrophytes, n=3) and a filamentous fungi (Fusarium oxysorum). The identification obtained with MALDI-TOF MS was compared with the identification by a traditional method under a microscope with lactofenol-blue stain or/and using a molecular method: amplification and subsequent sequencing of the ITS gene. The three protocols applied in this study were described as: one) The colony was displayed on the spot of the MALDI-TOF target, then the 2 µL of matrix (α-Cyano-4-hydroxycinnamic; two) the colony was displayed on the spot of MALDI-TOF target and 2 µl of formic acid, ending with the matrix (the same as in protocol one); three) firstly 2 µL /well of 100% formic acid was displayed on the MALDI-TOF MS without allowing it to dry, the colony was added, and finally, 2 µL of matrix (α-Cyano-4-hydroxycinnamic acid) were added and mixed, the plate was dried and the results were obtained via MALDI-TOF MS.
Results:Protocols 1 and 2 correctly identified 52% (13/25 in both cases) of the samples in comparison to the reference methods. Despite the lack of difference between protocols 1 and 2, there was a statistically significant difference with protocol 3, which was able to identify 92% of the samples (p=0.004586).
For a correct identification at species level, 1 to 12 replications were needed with a median of six replications .
According to our results, due to the absence of standardization, the identification of dermatophytes by MALDI-TOF MS is in a preliminary stage of development. Results of protocol three were promising, but they should be verified in a larger and more diverse group of samples.
Keyword(s): dermatophytes, filamentous fungi, MALDITOF MSCOI Other: The authors declare no conflict of interests
Session Type: ePosters
Session Title: ePosters
Authors(s): A. Manzanal, A. Sorarrain, M. Alonso, M. Ercibengoa, G. Cilla, M. Alkorta
Authors Affiliations(s): Biodonostia, Infectious Diseases Area, Respiratory Infection and Antimicrobial Resistance Group; Osakidetza Basque Health Service, Donostialdea Integrated Health Organisation, Microbiology Department, 20014 San Sebastian, Spain., Spain
Background:
The aim of this work was to compare three different protocols and to analyze how many replications were required for correct fungal identification by MALDI-TOF MS.
Methods:25 fungal samples from patients with onychomycosis were analyzed. The distribution was as follows: 24 dermatophytes (Trichophyton rubrum, n=16), (Trichophyton interdigitale; n=3), (Trichophyton mucoides, n=2), (Trichophyton mentagrophytes, n=3) and a filamentous fungi (Fusarium oxysorum). The identification obtained with MALDI-TOF MS was compared with the identification by a traditional method under a microscope with lactofenol-blue stain or/and using a molecular method: amplification and subsequent sequencing of the ITS gene. The three protocols applied in this study were described as: one) The colony was displayed on the spot of the MALDI-TOF target, then the 2 µL of matrix (α-Cyano-4-hydroxycinnamic; two) the colony was displayed on the spot of MALDI-TOF target and 2 µl of formic acid, ending with the matrix (the same as in protocol one); three) firstly 2 µL /well of 100% formic acid was displayed on the MALDI-TOF MS without allowing it to dry, the colony was added, and finally, 2 µL of matrix (α-Cyano-4-hydroxycinnamic acid) were added and mixed, the plate was dried and the results were obtained via MALDI-TOF MS.
Results:Protocols 1 and 2 correctly identified 52% (13/25 in both cases) of the samples in comparison to the reference methods. Despite the lack of difference between protocols 1 and 2, there was a statistically significant difference with protocol 3, which was able to identify 92% of the samples (p=0.004586).
For a correct identification at species level, 1 to 12 replications were needed with a median of six replications .
According to our results, due to the absence of standardization, the identification of dermatophytes by MALDI-TOF MS is in a preliminary stage of development. Results of protocol three were promising, but they should be verified in a larger and more diverse group of samples.
Keyword(s): dermatophytes, filamentous fungi, MALDITOF MSCOI Other: The authors declare no conflict of interests