Onychomycosis: Diagnosis made easy

Abstract

Background: Onychomycosis is the most prevalent nail disease, accounting to about 50% of all onychopathies. The diagnosis is still a challenge considering that the gold standard complementary test (direct microscopy and culture) may be false negative in many cases. Objectives: The study aimed to evaluate the role of dermoscopy in diagnosis of onychomycosis in comparison with scrap microscopic examination, mycological culture and histopathology and to detect how close the dermoscopic examination to the previous diagnostic findings. Patients and Methods: The present study included 20 patients suffered from onychomychosis and they were subjected to clinical, KOH microscopic, dermoscopic, mycological and histological examinations. Results: Jagged edge with spikes, longitudinal striations, distal irregular termination and ruin appearance are dermoscopic criteria of onychomychosis observed in 75% of cases. KOH examination was positive in only 20% of patients showing spores and hyphae. Culture was positive in only 35% of cases with M. canis, T. violaceum, T. rubrum, Chaetomium sp. and Scopulariopsis brumpt and there were no difference between the dermoscopic features caused by different organisms. The histologic evaluation showed found septate hyphea and blastoconidias within the amorphous keratin of the nail in 65%. Conclusions: Dermoscopy may be considered an easy, helpful, quite simple, quick and inexpensive technique for increasing the diagnostic accuracy of onychomycosis and could be a practical and effective diagnostic tool when mycology is not readily available. Mycology can, on the other hand, be avoided when nail dermoscopy fail to show any diagnostic sign of onychomycosis.