An improved molecular diagnostic assay for canine and feline dermatophytosis.
The few studies attempting to specifically characterize dermatophytes from hair samples of dogs and cats using PCR-based methodology relied on sequence-based analysis of selected genetic markers. The aim of the present investigation was to establish and evaluate a PCR-based approach employing genetic markers of nuclear DNA for the specific detection of dermatophytes on such specimens. Using 183 hair samples, we directly compared the test results of our one-step and nested-PCR assays with those based on conventional microscopy and in vitro culture techniques (using the latter as the reference method). The one step-PCR was highly accurate (AUC > 90) for the testing of samples from dogs, but only moderately accurate (AUC = 78.6) for cats. A nested-PCR was accurate (AUC = 93.6) for samples from cats, and achieved higher specificity (94.1 and 94.4%) and sensitivity (100 and 94.9%) for samples from dogs and cats, respectively. In addition, the nested-PCR allowed the differentiation of Microsporum canis from Trichophyton interdigitale (zoophilic) and geophilic dermatophytes (i.e., Microsporum gypseum or Trichophyton terrestre), which was not possible using the one step-assay. The PCRs evaluated here provide practical tools for diagnostic applications to support clinicians in initiating prompt and targeted chemotherapy of dermatophytoses.
Dipartimento di Sanità Pubblica e Zootecnia, Università degli Studi di Bari, Bari, Italy.
Claudia
C
Cafarchia
Robin B
RB
Gasser
Luciana A
LA
Figueredo
Stefania
S
Weigl
Patrizia
P
Danesi
Gioia
G
Capelli
Domenico
D
Otranto
D000818:Animals; D003883:Arthrodermataceae / Q000235:genetics / Q000302:isolation & purification*; D002371:Cat Diseases / Q000175:diagnosis* / Q000382:microbiology; D002415:Cats; D002687:Chitin Synthase / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D004283:Dog Diseases / Q000175:diagnosis* / Q000382:microbiology; D004285:Dogs; D005656:Fungal Proteins / Q000235:genetics; D005819:Genetic Markers / Q000235:genetics; D006197:Hair / Q000382:microbiology; D007558:Italy; D008864:Microsporum / Q000235:genetics / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012867:Skin / Q000473:pathology; D013045:Species Specificity; D014005:Tinea / Q000175:diagnosis / Q000382:microbiology / Q000662:veterinary*; D014249:Trichophyton / Q000235:genetics / Q000302:isolation & purification
D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D005656:Fungal Proteins; D005819:Genetic Markers; D002687:Chitin Synthase