ICD-10-CM > S00-T88 > T20-T25 > T25 > T25.5 > T25.59 > T25.591 T25.591 Corrosion of first degree of multiple sites of right ankle and foot Non-Billable/Non-Specific Codes T25.591A..., initial encounterT25.591D..., subsequent encounterT25.591S..., sequela