ICD-10-CM > S00-T88 > T20-T25 > T25 > T25.5 > T25.53 > T25.531 T25.531 Corrosion of first degree of right toe(s) (nail) Non-Billable/Non-Specific Codes T25.531A..., initial encounterT25.531D..., subsequent encounterT25.531S..., sequela