The Role of Scanning Electron Microscopy in the Direct Diagnosis of Onychomycosis

The purpose of this study was to evaluate the role of scanning electron microscopy (SEM) in the direct diagnosis ofsuspected onychomycosis with negative mycological test results.Methods. Outpatients diagnosed with suspected onychomycosiswith negative mycological test results, including direct microscopic examination with 10% potassium hydroxide (KOH) and fungalculture, on 3 separate occasions were recruited. A small piece of infected nail was obtained for SEM examination.Results. Amongthe 48 suspected onychomycosis samples, SEM revealed that 18 (37.5%) were positive for fungal structures, including 10 (20.8%)cases of hyphae and 8 (16.7%) cases of yeast blastospores or budding.Conclusion. SEM represents an effective method to diagnosesuspected onychomycosis when the traditional mycological methods were negative. Therefore, this technique could be used inclinical practice.