T21.50XA — Corrosion of first degree of trunk, unspecified site, initial encounter
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- Billing and coding for immunizations must follow the coverage indications, limitations, and medical necessity criteria set forth in the associated Local Coverage Determination LCD L34596 (Immunizations).
- The article provides billing/coding guidance that complements LCD L39400; use the documentation, prior authorization, and claim submission requirements specified in LCD L39400 and the local contractor's instructions.
- Document the injury or exposure details and the clinician's determination that the encounter meets criteria for post-exposure vaccination (e.g., wound characteristics, exposure type).
- Document patient immunization history, including dates of primary immunization and most recent booster, to support tetanus and rabies vaccine decisions.
Key Coverage Criteria
- No specific clinical indications are listed in this article; follow the Local Coverage Determination (LCD) L39400 for indications for magnesium testing or services.
- When the patient has not been previously immunized for rabies, coverage includes RIG (half IM and half wound on day 0) plus HDCV on days 0, 3, 7, 14, and 28.
- Vaccinations are covered only when directly related to treatment of an injury or direct exposure to a disease/condition listed in this policy.
- Preventive immunizations are covered for pneumococcal, hepatitis B, and influenza vaccines.
- Tdap or Td vaccines are covered when given for an acute injury in a person who is incompletely immunized for tetanus.
- For tetanus-prone wounds, tetanus toxoid (booster) should be administered if the patient has not had a booster dose within the past 5 years.
4 Active Policies
A56900 — Billing and Coding: Immunizations
J05
L34596 — Immunizations
J05
A59186 — Billing and Coding: Magnesium
L39400 — Magnesium
Related Codes
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