T78.3XXS ICD-10-CM Code: Angioneurotic edema, sequela
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Inpatient Payment Groups (MS-DRG)
MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0, Appendix B.
- MS-DRG 922 — OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITH MCC (MDC 21)
- MS-DRG 923 — OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITHOUT MCC (MDC 21)
A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.
Official Registry Overview & Definition
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for T78.3XXS in the official ICD-10-CM tabular list.
Inclusion Terms
Alternative terms the tabular list files under this code.
- Allergic angioedema
- Giant urticaria
- Quincke's edema
Excludes1 — Not Coded Here
Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
- serum urticaria (T80.6-) Compare T78.3XXS vs T80.6 →
- urticaria (L50.-) Compare T78.3XXS vs L50 →
Excludes2 — Not Included Here
Conditions not covered by this code, but which may be reported alongside it when both are present.
- complications of surgical and medical care NEC (T80-T88) Compare T78.3XXS vs T80 →
Code Also
Additional codes that may be required to fully describe the encounter.
- Code also, if applicable, place of occurrence, such as:
- highway rest stop (Y92.523)
- school (private) (public) (state) as the place of occurrence of the external cause (Y92.21-)
- service areas as the place of occurrence of the external cause (Y92.52-)
- single-family non-institutional (private) house as the place of occurrence of the external cause (Y92.01-)
- transport vehicle as the place of occurrence of the external cause (Y92.81-)
Frequently Compared Codes
The official Excludes notes on T78.3XXS name these codes. Each comparison page covers when the two can — or must not — be reported together.
Change history
No changes recorded for this code — unchanged since the FY2016 baseline of the change ledger.
Verify Before Coding
- No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim.
Relationships & Classification
Official ICD-10-CM tabular notes on other codes that name T78.3XXS or its code family.
1 Excludes1 notes: T75 (via T78.-).
Potential MS-DRG Relationships (FY2026)
Not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity.
Named in the grouper logic of 2 MS-DRGs: DRG 922 (MDC 21), DRG 923 (MDC 21).
From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.
Clinical classification (AHRQ CCSR):INJ073 — Injury, sequela (default).
Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.
Contextual Map
Every relationship of T78.3XXS in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Hierarchy
- S00-T88 — Chapter 19: Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) (S00-T88) [Hierarchy]
- T66-T78 — Other and unspecified effects of external causes [Hierarchy]
Referenced by Excludes1 notes
- T75 — Other and unspecified effects of other external causes [Excludes1](via T78.-): “adverse effects NEC (T78.-)” · check together
Clinical classification (CCSR)
- INJ073 — Injury, sequela [CCSR]
Potential MS-DRG
- DRG 922 — OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITH MCC [MS-DRG]: “OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITH MCC (MDC 21)”
- DRG 923 — OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITHOUT MCC [MS-DRG]: “OTHER INJURY, POISONING AND TOXIC EFFECT DIAGNOSES WITHOUT MCC (MDC 21)”
MDC crossing · procedures (32029)
- MDC 21 — Injuries, Poisonings and Toxic Effects of Drugs [MDC crossing]: “Injuries, Poisonings and Toxic Effects of Drugs — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs.”
- 0016070 — Bypass Cerebral Ventricle to Nasopharynx with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Nasopharynx with Autologous Tissue Substitute, Open Approach — grouped in MDC 21, the procedure side of this code's crossing.” · check together
- 0016071 — Bypass Cerebral Ventricle to Mastoid Sinus with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Mastoid Sinus with Autologous Tissue Substitute, Open Approach — grouped in MDC 21, the procedure side of this code's crossing.” · check together
- 0016072 — Bypass Cerebral Ventricle to Atrium with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Atrium with Autologous Tissue Substitute, Open Approach — grouped in MDC 21, the procedure side of this code's crossing.” · check together
- 0016073 — Bypass Cerebral Ventricle to Blood Vessel with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Blood Vessel with Autologous Tissue Substitute, Open Approach — grouped in MDC 21, the procedure side of this code's crossing.” · check together
- 0016074 — Bypass Cerebral Ventricle to Pleural Cavity with Autologous Tissue Substitute, Open Approach [Same-MDC procedure]: “Bypass Cerebral Ventricle to Pleural Cavity with Autologous Tissue Substitute, Open Approach — grouped in MDC 21, the procedure side of this code's crossing.” · check together
- and 32024 more
Nearest codes (40)
- T78 — Adverse effects, not elsewhere classified [Sibling]
- T78.120 — Other adverse food reaction due to egg with tolerance to baked egg [Sibling]
- T78.120A — Other adverse food reaction due to egg with tolerance to baked egg, initial encounter [Sibling]
- T78.120D — Other adverse food reaction due to egg with tolerance to baked egg, subsequent encounter [Sibling]
- T78.120S — Other adverse food reaction due to egg with tolerance to baked egg, sequela [Sibling]
- T78.121 — Other adverse food reaction due to egg with reactivity to baked egg [Sibling]
- T78.121A — Other adverse food reaction due to egg with reactivity to baked egg, initial encounter [Sibling]
- T78.121D — Other adverse food reaction due to egg with reactivity to baked egg, subsequent encounter [Sibling]
- and 32 more
Frequently Asked Questions (FAQ) & Clinical Guidance
Does T78.3XXS require a 7th character?
Yes. The appropriate 7th character is to be added to each code from category T78.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to T78.3XXS in its code family, with their registry titles.
- T78.2XXD — Anaphylactic shock, unspecified, subsequent encounter
- T78.2XXS — Anaphylactic shock, unspecified, sequela
- T78.3 — Angioneurotic edema
- T78.3XXA — Angioneurotic edema, initial encounter
- T78.3XXD — Angioneurotic edema, subsequent encounter
- T78.4 — Other and unspecified allergy
- T78.40 — Allergy, unspecified
- T78.40XA — Allergy, unspecified, initial encounter
- T78.40XD — Allergy, unspecified, subsequent encounter
- T78.40XS — Allergy, unspecified, sequela