Neocucurbitaria keratinophila: An emerging opportunistic fungus causing superficial mycosis in Spain

Med Mycol. 2019 Aug 1;57(6):733-738. doi: 10.1093/mmy/myy132.

Abstract

Although there have been few reports of opportunistic infections (superficial and systemic) caused by coelomycetous fungi, they are becoming more frequent. Neocucurbitaria keratinophila (formerly Pyrenochaeta keratinophila), characterized by producing pycnidial conidiomata and small hyaline conidia, seems to be an emergent opportunistic pathogen in Spain. Since this fungus was first reported from human keratitis, eight strains have been isolates from clinical cases in Spain. This is a retrospective study of these fungal strains, including phenotypic and molecular characterizations, and in vitro antifungal susceptibility assays. These clinical strains were identified by sequencing four phylogenetic markers such as the internal transcribed spacer region (ITS1-5.8S-ITS2) and fragments of the 28S nrRNA (LSU), beta-tubulin (tub2), and RNA polymerase II subunit 2 (rpb2) genes, and by morphological characterization. All the strains tested were susceptible to the majority of antifungals, being isavuconazole the only drug that showed a poor antifungal activity.

Keywords: Neocucurbitaria; Pyrenochaeta; antifungal susceptibility; coelomycetes; superficial mycosis.

MeSH terms

  • Antifungal Agents
  • Ascomycota / drug effects
  • Ascomycota / genetics
  • Ascomycota / pathogenicity*
  • Communicable Diseases, Emerging / epidemiology
  • Communicable Diseases, Emerging / microbiology*
  • DNA, Fungal / genetics
  • DNA, Ribosomal Spacer / genetics
  • Dermatomycoses / epidemiology*
  • Dermatomycoses / microbiology
  • Humans
  • Opportunistic Infections / epidemiology*
  • Opportunistic Infections / microbiology
  • Phenotype
  • Phylogeny
  • RNA, Ribosomal, 28S / genetics
  • Retrospective Studies
  • Sequence Analysis, DNA
  • Spain / epidemiology

Substances

  • Antifungal Agents
  • DNA, Fungal
  • DNA, Ribosomal Spacer
  • RNA, Ribosomal, 28S