T21.70XA — Corrosion of third degree of trunk, unspecified site, initial encounter
Is T21.70XA billable?
Yes, but T21.70XA is an unspecified code. T21.70XA is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, T21.70XA is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting T21.70XA — the more specific alternatives are listed below.
More specific alternatives
- T21.71XACorrosion of third degree of chest wall, initial encounter
- T21.72XACorrosion of third degree of abdominal wall, initial encounter
- T21.73XACorrosion of third degree of upper back, initial encounter
- T21.74XACorrosion of third degree of lower back, initial encounter
- T21.75XACorrosion of third degree of buttock, initial encounter
- T21.76XACorrosion of third degree of male genital region, initial encounter
- T21.77XACorrosion of third degree of female genital region, initial encounter
- T21.79XACorrosion of third degree of other site of trunk, initial encounter
T21.70XA at a glance
| Code | T21.70XA |
|---|---|
| Description | Corrosion of third degree of trunk, unspecified site, initial encounter |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
| 7th character "A" | initial encounter |
What does the 7th character "A" mean in T21.70XA?
In T21.70XA, the 7th character A means initial encounter. The 7th character is required for T21.70XA to be a valid, complete code.
Same condition, different episode of care — switch the 7th character:
Which MS-DRGs does T21.70XA group to?
T21.70XA sits in MDC 22 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 927Extensive Burns or Full Thickness Burns with MV >96 Hours with Skin Graftsurgical
- 933Extensive Burns or Full Thickness Burns with MV >96 Hours without Skin Graftmedical
As a secondary diagnosis, T21.70XA is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG. It also carries Hospital-Acquired Condition category 05.
How is T21.70XA listed in the Alphabetic Index?
The Alphabetic Index lists these routes under T21.70, the nearest indexed parent of T21.70XA. Use them to find the family, then select the specific code.
- Corrosion › trunk › third degree (injury) (acid) (caustic) (chemical) (lime) (external) (internal)
Code first — inherited from T21.7
The underlying condition below must be sequenced before T21.70XA. T21.70XA describes a manifestation and cannot be the principal or first-listed diagnosis.
- (T51-T65) to identify chemical and intent
Use additional code — inherited from Chapter 19
Report an additional code alongside T21.70XA to fully describe the condition. T21.70XA is sequenced first.
- code to identify any retained foreign body, if applicable (Z18.-)
Use additional code — inherited from T20-T25
Report an additional code alongside T21.70XA to fully describe the condition. T21.70XA is sequenced first.
Use additional code — inherited from T21.7
Report an additional code alongside T21.70XA to fully describe the condition. T21.70XA is sequenced first.
- external cause code to identify place (Y92)
Excludes2 — not included here — inherited from Chapter 19
The conditions below are not part of T21.70XA, but a patient may have both at the same time. When documentation supports it, T21.70XA and the excluded code may both be reported.
Excludes2 — not included here — inherited from T21
The conditions below are not part of T21.70XA, but a patient may have both at the same time. When documentation supports it, T21.70XA and the excluded code may both be reported.
How long has T21.70XA existed?
T21.70XA has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.