ICD-10 Code K55.3 – Necrotizing enterocolitis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code K55.3 – Necrotizing enterocolitis
What it is
K55.3 identifies necrotizing enterocolitis, a serious inflammatory and ischemic bowel condition that can lead to intestinal tissue death. It is most often documented in newborns, especially premature infants.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings include abdominal distension, feeding intolerance, bloody stools, and signs of systemic illness or bowel perforation.
When to use this code
Use K55.3 when the provider documents necrotizing enterocolitis as the diagnosis. Apply it for confirmed cases, or when the record clearly states NEC without a more specific site or severity detail. Check documentation if the note suggests suspected disease only.
Do not use for
Do not use this code for nonspecific neonatal feeding problems, isolated abdominal distension, or other enterocolitis types. If the chart documents a different bowel disorder, code that condition instead.
Coding tip
Review the neonatal record carefully for specificity, and code only what the provider explicitly documents.