Onychomycosis insensitive to systemic terbinafine and azole treatments reveals non-dermatophyte moulds as infectious agents.
BACKGROUND
Dermatophytes are the main cause of onychomycoses, but various non-dermatophyte filamentous fungi are often isolated from abnormal nails.


OBJECTIVE
Our aim was the in situ identification of the fungal infectious agent in 8 cases of onychomycoses which could not be cured after systemic terbinafine and itraconazole treatment.


METHODS
Fungal DNA was extracted from nail samples, and infectious fungi were identified by restriction fragment length polymorphism (RFLP) of amplified fungal ribosomal DNA using a previously described PCR/RFLP assay.


RESULTS
PCR/RFLP identification of fungi in nails allows the identification of the infectious agent: Fusarium sp., Acremonium sp. and Aspergillus sp. were found as a sole infectious agent in 5, 2 and 1 cases, respectively.


CONCLUSIONS
Fusarium spp. and other non-dermatophyte filamentous fungi are especially difficult to cure in onychomycoses utilising standard treatment with terbinafine and itraconazole. PCR fungal identification helps demonstrate the presence of moulds in order to prescribe alternative antifungal treatments.
Baudraz-Rosselet
Florence
F
Department of Dermatology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
Ruffieux
Catherine
C
Lurati
Massimo
M
Bontems
Olympia
O
Monod
Michel
M
D000164:Acremonium / Q000302:isolation & purification; D000328:Adult; D000935:Antifungal Agents / Q000627:therapeutic use*; D001230:Aspergillus / Q000302:isolation & purification; D005260:Female; D015725:Fluconazole / Q000627:therapeutic use; D005533:Foot Dermatoses / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology; D005670:Fusarium / Q000302:isolation & purification; D006801:Humans; D017964:Itraconazole / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009025:Morpholines / Q000627:therapeutic use; D009281:Naphthalenes / Q000627:therapeutic use*; D014009:Onychomycosis / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology; D012150:Polymorphism, Restriction Fragment Length; D000077291:Terbinafine
D000935:Antifungal Agents; D009025:Morpholines; D009281:Naphthalenes; D017964:Itraconazole; D015725:Fluconazole; C038974:amorolfine; D000077291:Terbinafine