ICD-10-CM > S00-T88 > T20-T25 > T23 > T23.5 > T23.52 > T23.522 T23.522 Corrosion of first degree of single left finger (nail) except thumb Non-Billable/Non-Specific Codes T23.522A..., initial encounterT23.522D..., subsequent encounterT23.522S..., sequela