Abstract
Since traditional diagnosis of dermatophyte infections is slow, we present a rapid new PCR test for detection of Trichophyton spp., Microsporum canis and M. audouinii infections. The performance of the test was evaluated with: 58 dermatophyte isolates; 10 yeast, mould and human DNA control samples; 25 routine specimens from patients suspected of having dermatophytosis; 10 hair specimens from guinea pigs experimentally infected with M. canis; and two samples from un-infected control animals. DNA was prepared by a 10-min procedure from pure cultures as previously described. The 302 bp PCR product was obtained for 35/35 Trichophyton isolates (10 species included) and the 279 bp for 3/3 M. canis and 4/4 M. audouinii samples. None of the 2 E. floccosum, 11 M. gypseum, 3 M M. persicolor or 12 control samples (yeast, mould, human DNA) were positive with either of the two PCR tests. Among the patient specimens, seven were T. rubrum positive, two for T. mentagrophytes, one was positive for T. tonsurans and 15 were dermatophyte negative by routine investigation (culture and/or pan-dermatophyte + T. rubrum multiplex PCR). The PCR results with our procedures were in 100% agreement with these results. Finally, the Microsporum PCR was positive for 10/10 guinea pig specimens from infected animals but for 0/2 of the control animal samples. The evaluation of the two PCR tests indicated excellent sensitivity and specificity.
Declarations of interest:
Anna Brillowska-Dabrowska: None
Aleksandra Świerkowska: None
Ditte Marie Lindhardt Saunte has received honoraries for speaking from Galderma, Schering-Plough, Medinor A/S and reimbursement of travel expenses Swedish Orphan. Ditte Marie Saunte holds no stocks or shares, and owns no patents.
Maiken Cavling Arendrup has received honoraries for speaking, consultancy, advisory board membership, or reimbursement of travel expenses from Merck Sharp and Dohme, Pfizer, Scheering Plough, Swedish Orphan, Astellas, Mycognostica, and SpePharm. Maiken Cavling Arendrup has received research funding from Merck, Astellas and Pfizer. Maiken Cavling Arendrup holds no stocks or shares, and owns no patents.
This paper was first published online on Early Online on 22 October 2009.