Main Article Content
Onychomycosis is fungal infection of nail and usually mild disease. However, the onychomycosis can impact quality of life of patient. Accurate diagnosis is crucial for successful treatment of onychomycosis. Unfortunately, the diagnostic preciseness of conventional diagnosis by using potassium hydroxide (KOH) preparation and fungal culture is not ideal. The aim of this study was to evaluate the detection of fungal infection in nail by ribosomal DNA (rDNA) sequence analysis. One-hundred and sixty-eight nail samples were subjected for fungal detection by rDNA sequence analysis. The result obtained by rDNA sequence analysis was compared to conventional methods. The study found that positive rates of KOH preparation, culture and rDNA sequence analysis were 32.1, 24.4 and 32.7 %, respectively. There was concordance between rDNA sequence analysis and culture as a standard method in 75.0 %. The sensitivity, specificity, positive predictive value and negative predictive value of rDNA sequence analysis were 65.9, 78.0, 49.1 and 87.6 %, respectively. The positive rate of conventional culture method in combination with rDNA sequence analysis increased to 41.1 %. The results support the use of the rDNA sequence analysis in combination with conventional laboratory tests for accurate identiﬁcation of fungi in nail sample.
Keywords: onychomycosis; potassium hydroxide preparation; culture; rDNA sequence analysis
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