ICD-10-CM > S00-T88 > T20-T25 > T21 > T21.5 T21.5 Corrosion of first degree of trunk Non-Billable/Non-Specific Code First (T51-T65) to identify chemical and intent Use Additional external cause code to identify place (Y92) Codes T21.50Corrosion of first degree of trunk, unspecified siteT21.50XA..., initial encounterT21.50XD..., subsequent encounterT21.50XS..., sequelaT21.51Corrosion of first degree of chest wallT21.51XA..., initial encounterT21.51XD..., subsequent encounterT21.51XS..., sequelaT21.52Corrosion of first degree of abdominal wallT21.52XA..., initial encounterT21.52XD..., subsequent encounterT21.52XS..., sequelaT21.53Corrosion of first degree of upper backT21.53XA..., initial encounterT21.53XD..., subsequent encounterT21.53XS..., sequelaT21.54Corrosion of first degree of lower backT21.54XA..., initial encounterT21.54XD..., subsequent encounterT21.54XS..., sequelaT21.55Corrosion of first degree of buttockT21.55XA..., initial encounterT21.55XD..., subsequent encounterT21.55XS..., sequelaT21.56Corrosion of first degree of male genital regionT21.56XA..., initial encounterT21.56XD..., subsequent encounterT21.56XS..., sequelaT21.57Corrosion of first degree of female genital regionT21.57XA..., initial encounterT21.57XD..., subsequent encounterT21.57XS..., sequelaT21.59Corrosion of first degree of other site of trunkT21.59XA..., initial encounterT21.59XD..., subsequent encounterT21.59XS..., sequela