title: Using a polymerase chain reaction as a complementary test to improve the detection of dermatophyte fungus in nails.
abstract: BACKGROUND
  Dermatomycoses are a group of pathologic abnormalities frequently seen in clinical practice, and their prevalence has increased in recent decades. Diagnostic confirmation of mycotic infection in nails is essential because there are several pathologic conditions with similar clinical manifestations. The classical method for confirming the presence of fungus in nail is microbiological culture and the identification of morphological structures by microscopy.
  
  
  METHODS
  We devised a nested polymerase chain reaction (PCR) that amplifies specific DNA sequences of dermatophyte fungus that is notably faster than the 3 to 4 weeks that the traditional procedure takes. We compared this new technique and the conventional plate culture method in 225 nail samples. The results were subjected to statistical analysis.
  
  
  RESULTS
  We found concordance in 78.2% of the samples analyzed by the two methods and increased sensitivity when simultaneously using the two methods to analyze clinical samples. Now we can confirm the presence of dermatophyte fungus in most of the positive samples in just 24 hours, and we have to wait for the result of culture only in negative PCR cases.
  
  
  CONCLUSIONS
  Although this PCR cannot, at present, substitute for the traditional culture method in the detection of dermatophyte infection of the nails, it can be used as a complementary technique because its main advantage lies in the significant reduction of time used for diagnosis, in addition to higher sensitivity.
authors.forename: María José Iglesias
authors.initials: MJ
authors.lastname: Sánchez
authors.forename: Ana María Pérez
authors.initials: AM
authors.lastname: Pico
authors.forename: Félix Marcos
authors.initials: FM
authors.lastname: Tejedor
authors.forename: María Jesús Iglesias
authors.initials: MJ
authors.lastname: Sánchez
authors.forename: Raquel Mayordomo
authors.initials: RM
authors.lastname: Acevedo
mesh_terms: D003883:Arthrodermataceae / Q000302:isolation & purification*; D004271:DNA, Fungal / Q000032:analysis; D005260:Female; D005533:Foot Dermatoses / Q000175:diagnosis; D006229:Hand Dermatoses / Q000175:diagnosis; D006801:Humans; D008297:Male; D014009:Onychomycosis / Q000175:diagnosis*; D016133:Polymerase Chain Reaction / Q000379:methods* / Q000706:statistics & numerical data; D058996:Quality Improvement; D015203:Reproducibility of Results; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D013030:Spain
chemical_list: D004271:DNA, Fungal