Application Of Dermatoscopy In Diagnosis And Treatment Of Onychomycosis Caused By Different Types Of Fungi

Background:Onychomycosis is a kind of yeast by skin versicolor bacterium or skin ringworm fungi refers to（foot）armour fungal infection caused by mold.The traditional method of diagnosis of onychomycosis is mycology examination with low microscopic positive rate,while fungal culture takes long.Dermoscope is a kind of noninvasive simple and fast nondestructive inspection method,but in the application of onychomycosis and research is yet to be explored.Objectives:The purpose of this study was to compare the dermatoscopic characteristics and model characteristics of onychomycosis patients with different fungal infections,and to observe the changes of dermatoscopy before and after systemic antifungal therapy,so as to explore whether dermatoscopy can be used as a new method for determining the efficacy of onychomycosis.Methods:A total of 112 patients diagnosed with onychomycosis from November 2020 to February 2022,including 188 cases of onychomycosis,were selected for retrospective analysis of their clinical data and dermatoscopic manifestations and patterns.SPSS26.0statistical analysis software was used for statistical processing of the data,and Pearson test and Fisher test were used S exact probability method,the dermatoscopic characteristics and patterns of each group of patients were analyzed,P value <0.05 was considered as statistically significant difference between groups;The chi-square method was used for pial comparison between multiple groups.P values less than0.05/n（n was the number of comparisons）were considered statistically significant,and the dermatoscopic changes before and after systemic antifungal treatment were observed.Results:1.Among the 112 patients,there were 72 women,the age of onset was 19-73 years old,and the median was 34.5 years old;there were 40 men,the age of onset was 20-75 years old,and the median was 36.5 years old;and there were 46 nails and 142 toenails.2.The clinical subtypes of 188 cases were as follows: 127 cases（67.6%）were distal lateral subarmour type（DLSO）,10 cases（5.3%）were proximal subarmour type（PSO）,13 cases（6.9%）were white superficial armour type（SWO）,37 case s（19.7%）were total armour damage type（TDO）,and 1 case（0.5%）were indec k type（EO）.Dermatoscopy showed 52（27.7%）serrated edges,49（26.1%）longit udinal stripes,125（66.5%）deck thickening,123（65.4%）nail discoloration,149（79.3%）subnail keratin and detritus deposition,150（79.8%）perinail dry desqua mination,and 75（3）tarnish deck 9.9%),conical nail keratosis 45（24.0%）,marb led turbidness 25（13.3%）,punctured turbidness 36（19.1%）,nail dissection 55（29.3%）,subnail hemorrhage 48（25.5%）.Dermatoscopic patterns included 52 short spikes（27.7%）,51 longitudinal stripes（27.1%）,53 linear edges（28.2%）,and 32 remote irregular interruptions（17.0%）.3.Analysis by SPSS 26.0 software showed that among 188 onychomycosis onychomycosis,clinical subtypes DLSO and TDO showed no statistical difference between dermatophyte group,yeast group,mycobacterium group and mixed infection group（P>0.05）Dermatologic features: serrated edges（P<0.05）longitudinal fringe（P<0.01）Dry and desquamated skin（P<0.01）Keratinization of conical nail（P< 0.01）Subnail hemorrhage（P<0.01）Dermatoscopic patterns were statistically significant in tinea dermatophyllum group,yeast group,mold group and mixed infection group: short spinous pattern（P<0.01）longitudinal fringe pattern（P<0.01）Linear edge mode（P<0.01）There were statistically significant differences in the tinea dermatophyllum group,yeast group,mold group and mixed infection group,and there was no statistically significant difference in the distal irregular interruption pattern in these four groups（P>0.05）.4.Selected seven skin ringworm fungi infection DLSO short spiny mode of onychomycosis patients,after treatment with systemic antifungal,fungus periodic review of immunofluorescence staining microscopy and skin test,followed up for 5months,skin thickening microscopically found that patients with deck A keratin clastic sediments under the first better,serrated edge finally getting better.Conclusions:The dermatoscopic manifestations of onychomycosis caused by different types of fungi are characteristic,and can be used as an auxiliary diagnostic method for clinical onychomycosis,and can be used to evaluate the effect of antifungal treatment.