ICD-10 K52.21
Billable / SpecificFood protein-induced enterocolitis syndrome
About ICD-10-CM K52.21
ICD-10-CM code K52.21 represents Food protein-induced enterocolitis syndrome. This is a billable/specific code in the Digestive System chapter (block K52). The 2026 edition of ICD-10-CM K52.21 became effective on October 1, 2025.
Inclusion Terms / Approximate Synonyms
Clinical terms and conditions classified under K52.21. Per CMS ICD-10-CM Tabular 2026.
- FPIES
Use Additional Code
When coding K52.21, also report these additional codes when applicable.
- code for hypovolemic shock, if present (R57.1)
Medicare LCD Coverage for K52.21
Local Coverage Determinations (LCDs) from CMS MACs that list K52.21 as a covered diagnosis.
Showing top 10 of 356 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing K52.21.
5 Medicare
1 Aetna
CPT Codes Commonly Billed with K52.21
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
We don't have CPT pairings indexed for this specific code yet. Use the CPT search above to find common procedures, or check your payer's published medical policy for code-specific guidance.
Convert K52.21 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| K52.21 | 5583 | 10000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To K52.21
Other codes in section K50-K52 (Noninfective enteritis and colitis).
ICD-10 K52.21, Billing FAQ
Is ICD-10 code K52.21 billable? +
Yes, K52.21 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
What other names or terms map to K52.21? +
ICD-10 K52.21 includes: FPIES.
What ICD-9 codes does K52.21 map to? +
Per CMS GEMs, K52.21 maps to ICD-9 codes: 5583. Useful for legacy data review and historical claim analysis.
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Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
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