Sánchez AK, Fernández MRF, Moreno MME, Villegas AL, Meneses GF, Arenas GR

Language: Spanish
References: 14
Page: 261-266
PDF size: 219.03 Kb.

ABSTRACT

Introduction: The growing importance of onychomycosis, not only by the increase in frequency but also by the rise of emerging pathogens poses a diagnostic and therapeutic challenge.
Material and methods: A comparative, open, observational, transversal, which included patients with clinical diagnosis of onychomycosis and compared the diagnostic utility of direct examination of KOH-chlorazol black and calcofluor white, on the gold standard biopsy of the distal portion of the nail plate stained with PAS.
Results:We included 165 patients (70% women), 79.4% were positive for onychomycosis (OSDL 50.9%) in toenails (89%) with 6 years of evolution. They reported a sensitivity: KOH-black of chlorazol 90.12% (95% CI: 81.46% -95.63%) vs 86.42% calcofluor white (95% CI: 76.99% -93.01%) and a specificity of 50% KOH-black of chlorazol (95% CI: 38.89% -61.11%) vs 60.71% for calcofluor white (95% CI: 49.45% -71.20%). Also, there was a PPV of 63.48% for chlorazol KOH-black (95% CI: 53.99% -72.26%) and 67.96% for calcofluor white (95% CI: 58.04% -76.81%) and a NPV of 84% (95% CI: 70.88% - 92.81%) and 82.26% (95% CI: 70.46% -90.78%), respectively.
Comment: The direct examination with calcofluor white is a good diagnostic tool because it is highly sensitive, requires little expertise on the part of the observer, is performed by simple processing, which consumes little time and is inexpensive.

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