Examining the accuracy of visual diagnosis of tinea pedis and tinea unguium in aged care facilities

Objective: The aim of this study was to examine the accuracy of visual diagnosis of tinea pedis (Athlete's foot) and tinea unguium (fungal nail infection), as well as to provide information on skin abnormalities that could help identify these diseases in aged care facilities (long-term care facilities (LTCFs) and nursing homes). Method: A multicentre, cross-sectional observational study was conducted in a LTCF and two nursing homes. A dermatologist observed the skin abnormalities in the participants' interdigital and plantar areas, to screen for tinea pedis, and in the participants' toenails, to screen for tinea unguium. If abnormalities were noted, samples such as scales or toenails were collected and examined using direct microscopy. The accuracy of the macroscopic observation for each skin abnormality was examined. Results: A total of 173 residents were recruited. The accuracy of clinical diagnosis using macroscopic observation was relatively low. The sensitivities and specificities for clinical diagnosis were 0.37 and 0.95 for tinea pedis in the interdigital areas, 0.47 and 0.94 for tinea pedis in the plantar areas, and 0.80 and 0.61 for tinea unguium in toenails, respectively. Scales in the plantar areas and discoloration of the toenails were more frequently observed in residents with tinea pedis and tinea unguium than in those without them. Conclusion: Several skin abnormalities were observed in the residents recruited in this study, but there was insufficient correlation with tinea pedis and tinea unguium to be used for screening. Declaration of interest: This study was partly supported by unrestricted research grants from the non-profit organisation Health Institute Research of Skin, Daiwa Securities Health Foundation, Chiyoda Mutual Life Foundation, St. Luke's Life Science Institute, and Japan Foundation for Aging and Health. No potential conflicts of interest were disclosed.