Molecular identification of Fusarium species in onychomycoses.
BACKGROUND
Fusarium species are isolated from about 3% of onychomycoses in the Swiss native population. On the basis of macroscopic characters and microscopic examination of the cultures, identification of Fusarium often remains difficult or uncertain because of variations from one isolate to another and overlapping characteristics between species.


OBJECTIVE
To obtain information about the prevailing species of Fusarium collected from onychomycoses.


METHODS
An analysis of the Fusarium specimens isolated in the Department of Dermatology at the University Hospital of Lausanne was conducted during a 2-year period (71 isolates). A 311-bp fragment of the gene encoding 28S rDNA was amplified by PCR and sequenced. DNA sequences were compared to those available for reference strains.


RESULTS
Fusarium oxysporum was the most frequently isolated species, accounting for 54% of the isolates. F. proliferatum and 4 taxons belonging to the F. solani species complex were identified with an appreciable frequency ranging from 4 to 14%.


CONCLUSIONS
The Fusarium species identified were the same as those known to cause disseminated fusariosis in immunocompromised patients. The presence of these Fusarium species in onychomycoses warrants that careful attention should be paid to abnormal nails before beginning immunosuppressive treatments in patients.
Ninet
Béatrice
B
Division des Maladies Infectieuses, Hôpital Cantonal Universitaire, Genève, Switzerland.
Jan
Isabelle
I
Bontems
Olympia
O
Léchenne
Barbara
B
Jousson
Olivier
O
Lew
Daniel
D
Schrenzel
Jacques
J
Panizzon
Renato G
RG
Monod
Michel
M
D001483:Base Sequence; D017931:DNA Primers; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D005670:Fusarium / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008969:Molecular Sequence Data; D014009:Onychomycosis / Q000453:epidemiology* / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D015995:Prevalence; D013557:Switzerland / Q000453:epidemiology
D017931:DNA Primers; D004269:DNA, Bacterial; D004275:DNA, Ribosomal