Identification of a clonal population of Aspergillus flavus by MALDI-TOF mass spectrometry using deep learning.

Journal: Scientific reports
PMID:

Abstract

The spread of fungal clones is hard to detect in the daily routines in clinical laboratories, and there is a need for new tools that can facilitate clone detection within a set of strains. Currently, Matrix Assisted Laser Desorption-Ionization Time-of-Flight Mass Spectrometry is extensively used to identify microbial isolates at the species level. Since most of clinical laboratories are equipped with this technology, there is a question of whether this equipment can sort a particular clone from a population of various isolates of the same species. We performed an experiment in which 19 clonal isolates of Aspergillus flavus initially collected on contaminated surgical masks were included in a set of 55 A. flavus isolates of various origins. A simple convolutional neural network (CNN) was trained to detect the isolates belonging to the clone. In this experiment, the training and testing sets were totally independent, and different MALDI-TOF devices (Microflex) were used for the training and testing phases. The CNN was used to correctly sort a large portion of the isolates, with excellent (> 93%) accuracy for two of the three devices used and with less accuracy for the third device (69%), which was older and needed to have the laser replaced.

Authors

  • Anne-Cécile Normand
    AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Service de Parasitologie-Mycologie, 75013, Paris, France. annececile.normand@aphp.fr.
  • Aurélien Chaline
    AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Service de Parasitologie-Mycologie, 75013, Paris, France.
  • Noshine Mohammad
    Sorbonne Université, INSERM, Institut Pierre Louis d'Epidémiologie et de Santé Publique, AP-HP, Hôpital Pitié-Salpêtrière, 75013, Paris, France.
  • Alexandre Godmer
    Département de Bactériologie, Hôpital Saint-Antoine, AP-HP, Sorbonne Université, Paris, France.
  • Aniss Acherar
    Sorbonne Université, INSERM, Institut Pierre Louis d'Epidémiologie et de Santé Publique, AP-HP, Hôpital Pitié-Salpêtrière, 75013, Paris, France.
  • Antoine Huguenin
    Université de Reims Champagne Ardenne, ESCAPE EA7510, 51100, Reims, France.
  • Stéphane Ranque
    IHU-Méditerranée Infection, 13005, Marseille, France.
  • Xavier Tannier
    Sorbonne Université, Inserm, Univ Paris 13, Laboratoire d'Informatique Médicale et d'Ingénierie des Connaissances pour la e-Santé, LIMICS, 75006 Paris, France. Electronic address: xavier.tannier@sorbonne-universite.fr.
  • Renaud Piarroux
    AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Service de Parasitologie-Mycologie, 75013, Paris, France.