K52.21 Food protein-induced enterocolitis syndrome

Billable ICD-10-CM code, FY2026.

Applicable to

• FPIES

Use additional code

• code for hypovolemic shock, if present (R57.1)

Applies from K52.2 Allergic and dietetic gastroenteritis and colitis

Applicable to

• Food hypersensitivity gastroenteritis or colitis

Excludes2 (not included here)

• allergic eosinophilic colitis (K52.82)
• allergic eosinophilic esophagitis (K20.0)
• allergic eosinophilic gastritis (K52.81)
• allergic eosinophilic gastroenteritis (K52.81)

Use additional code

• code to identify type of food allergy (Z91.01-, Z91.02-)

MS-DRG index

Defines the logic of DRG(s) 391-392 in MDC 06.

Approximate ICD-9-CM (GEMs)

• 558.3 Allergic gastroenteritis and colitis (approximate)

Code annotations containing back-references to K52.21

Back-references to K52.21

• Type 2 Excludes: K52.82 Eosinophilic colitis ("food protein-induced enterocolitis syndrome (FPIES) (K52.21)")
• Type 1 Excludes: T61 Toxic effect of noxious substances eaten as seafood ("food protein-induced enterocolitis syndrome (K52.21)")
• Type 1 Excludes: T62 Toxic effect of other noxious substances eaten as food ("food protein-induced enterocolitis syndrome (K52.21)")
• Type 2 Excludes: T78.1 Other adverse food reactions, not elsewhere classified ("food protein-induced enterocolitis syndrome (K52.21)")
• Type 1 Excludes: T78.4 Other and unspecified allergy ("food protein-induced enterocolitis syndrome (K52.21)")

Diagnosis Index entries for K52.21

• Allergy, allergic (reaction) (to) › milk protein › enterocolitis syndrome
• Colitis (acute) (catarrhal) (chronic) (noninfective) (hemorrhagic) › allergic › with › food protein-induced enterocolitis syndrome
• Enteritis (acute) (diarrheal) (hemorrhagic) (noninfective) › allergic › with › food protein-induced enterocolitis syndrome
• Enteritis (acute) (diarrheal) (hemorrhagic) (noninfective) › allergic › with › FPIES
• FPIES (food protein-induced enterocolitis syndrome)
• Gastroenteritis (acute) (chronic) (noninfectious) › allergic › with › food protein-induced enterocolitis syndrome
• Syndrome › food protein-induced enterocolitis (FPIES)

Nearby codes

• K52 Other and unspecified noninfective gastroenteritis and colitis
• K52.0 Gastroenteritis and colitis due to radiation
• K52.1 Toxic gastroenteritis and colitis
• K52.2 Allergic and dietetic gastroenteritis and colitis
• K52.21 Food protein-induced enterocolitis syndrome (this code)
• K52.22 Food protein-induced enteropathy
• K52.29 Other allergic and dietetic gastroenteritis and colitis
• K52.3 Indeterminate colitis
• K52.8 Other specified noninfective gastroenteritis and colitis
• K52.81 Eosinophilic gastritis or gastroenteritis