ICD-10-CM 2027
ICD-10 code for neonatal peritonitis
From the official ICD-10-CM alphabetic index entry “Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › neonatal”. Page updated September 29, 2026.
About coding neonatal peritonitis
The ICD-10-CM code for neonatal peritonitis is P78.1 (Other neonatal peritonitis). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on P78.1.
Within P78, choose P78.1 (Other neonatal peritonitis) only when documentation doesn't support a more specific option: perinatal intestinal perforation (P78.0), neonatal hematemesis and melena due to swallowed maternal blood (P78.2), noninfective neonatal diarrhea (P78.3), other specified perinatal digestive system disorders (P78.8) and perinatal digestive system disorder, unspecified (P78.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 794 (Neonate with Other Significant Problems, relative weight 1.4935), in MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific neonatal peritonitis codes (official index)
- meconium P78.0 — Perinatal intestinal perforation
Common questions about neonatal peritonitis ICD-10 codes
What is the ICD-10 code for neonatal peritonitis?
- P78.1 — Other neonatal peritonitis. More specific codes apply when the documentation supports them: P78.0.
What is the ICD-10 code for meconium neonatal peritonitis?
- P78.0 — Perinatal intestinal perforation.
Is P78.1 billable?
- Yes. P78.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can P78.1 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict P78.1 as a principal diagnosis.
Is P78.1 a CC or MCC?
- No. P78.1 is neither a CC nor an MCC under MS-DRG v44.0.