Patrones dermatoscópicos en pacientes con diagnóstico clínico de onicomicosis y examen micológico directo positivo

Abstract

IntroductionOnychomycosis is one of the most common nail disorders, representing almost 50% of them. The sensitivity and specificity of direct examination and mycological culture for diagnosis can be as low as 15%. The objective of this study was to describe dermatoscopic patterns in cases of onychomycosis confirmed by direct examination and to correlate them with the type of causal fungal agent and the clinical subtype of onychomycosis. Material and methodA prospective observational and descriptive cross-sectional study of 45 patients with clinical suspicion of onychomycosis was conducted. All patients underwent clinical examination, dermatoscopy with HEINE mini 3000 dermatoscopy, direct mycological examination with KOH and culture analysis. The most frequent dermatoscopic patterns were identified and their correlation with the type of causal fungal agent and the clinical subtype of onychomycosis were analyzed. Results40 patients with clinical suspicion of onychomycosis and positive direct mycological examination were included. 22 (55%) patients had lateral distal subungual onychomycosis, 12 (30%) total dystrophic onychomycosis, and 6 (15%) superficial white onychomycosis. The dermatoscopic patterns of onychomycosis found were: focal macular in 6 (15%) cases, longitudinal striations in 12 (30%), jagged edge with spikes in 11 (27.5%) and distal irregular termination in 11 (27.5%) patients. Focal macular pattern was associated with lateral distal subungual onychomycosis (p = 0.002) and dermatophyte non mycelial fungus (p = 0.0001), the presence of longitudinal striations was associated with lateral distal subungual onychomycosis (p = 0.005) and dermatophyte fungus (p = 0.0001), jagged edge with spikes was associated with lateral distal subungual onychomycosis (p = 0.005) and dermatophyte fungus (p = 0.0001), finally distal irregular termination pattern was associated with total dystrophic onychomycosis (p = 0.0001), dermatophyte fungi (p = 0.0001) and yeasts (p = 0.004). ConclusionDermoscopy is a simple and fast technique that can provide immediate information to guide the diagnosis of onychomycosis.