title: Aspergillus species as emerging causative agents of onychomycosis.
abstract: BACKGROUND
  Onychomycosis is a common nail infection caused by dermatophytes, non-dermatophyte molds (NDM), and yeasts. Aspergillus species are emerging as increasing causes of toenail onychomycosis. The purpose of this study was species delineation of Aspergillus spp. isolated from patients with onychomycosis.
  
  
  METHODS
  During a period of one year (2012-2013), nail samples were collected from patients clinically suspected of onychomycosis and subjected to microscopic examination and culture. Species identification was performed based on macro- and micro-morphology of colonies. For precise species identification, PCR-amplification and sequencing of the beta-tubulin gene followed by BLAST queries were performed where required.
  
  
  RESULTS
  A total of 463/2,292 (20.2%) tested nails were diagnosed with onychomycosis. Among the positive specimens, 154 cases (33.2%) were identified as saprophytic NDM onychomycosis, 135 (29.2%) of which were attributable to Aspergillus. Aspergillus species isolated from the infected nails included Aspergillus flavus (77.3%, n=119), Aspergillus niger (n=4), Aspergillus tubingensis (n=4), Aspergillus terreus (n=3), Aspergillus sydowii (n=2), Aspergillus spp. (n=2), and Aspergillus candidus (n=1). Among the patients diagnosed with onychomycosis due to Aspergillus (average patient age, 47.4 years), 40 had fingernail and 95 toenail involvement. The large toenails were most commonly affected.
  
  
  CONCLUSIONS
  This study identified a markedly high occurrence of A. flavus, and this fungus appears to be an emerging cause of saprophytic onychomycosis in Iran. The study moreover highlights the necessity of differentiating between dermatophytic and non-dermatophytic nail infections for informed decisions on appropriate therapy.
authors: Department of Medical Parasitology and Mycology, School of Public Health, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran.
authors: S
authors: S
authors: Nouripour-Sisakht
authors: Department of Medical Parasitology and Mycology, School of Public Health, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: mirhendi@tums.ac.ir.
authors: H
authors: H
authors: Mirhendi
authors: Department of Medical Parasitology and Mycology, School of Public Health, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran.
authors: M R
authors: MR
authors: Shidfar
authors: Department of Medical Parasitology and Mycology, School of Public Health, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran.
authors: B
authors: B
authors: Ahmadi
authors: Department of Medical Mycology, School of Medicine, Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
authors: A
authors: A
authors: Rezaei-Matehkolaei
authors: Department of Medical Parasitology and Mycology, School of Public Health, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran.
authors: M
authors: M
authors: Geramishoar
authors: Department of Medical Parasitology and Mycology, School of Public Health, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran.
authors: F
authors: F
authors: Zarei
authors: Department of Medical Parasitology and Mycology, School of Public Health, National Institute of Health Research, Tehran University of Medical Sciences, Tehran, Iran.
authors: N
authors: N
authors: Jalalizand
mesh_terms: D001230:Aspergillus / Q000145:classification / Q000302:isolation & purification*; D021821:Communicable Diseases, Emerging / Q000453:epidemiology / Q000382:microbiology*; D005533:Foot Dermatoses / Q000453:epidemiology / Q000382:microbiology; D006229:Hand Dermatoses / Q000453:epidemiology / Q000382:microbiology; D006801:Humans; D007492:Iran / Q000453:epidemiology; D014009:Onychomycosis / Q000453:epidemiology* / Q000382:microbiology*
keywords: Aspergillus; Aspergillus flavus; Onychomycose; Onychomycosis