Problem analysis: Hello, this situation should be considered to be due to tinea pedis causes gray nails, this and fungal infection is related. In addition, delayed treatment can be the spread of the fungus

Suggestions: you can go to the hospital dermatology department to see, the drug can use some itraconazole to oral, generally can be treated. The other is to try not to scratch, to prevent the occurrence of ringworm

Hope to help you, and wish you a speedy recovery

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