ICD-10-CM 2027
ICD-10 code for diphtheritic peritonitis
From the official ICD-10-CM alphabetic index entry “Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › diphtheritic”. Page updated September 29, 2026.
About coding diphtheritic peritonitis
The ICD-10-CM code for diphtheritic peritonitis is A36.89 (Other diphtheritic complications).
Within A36.8, choose A36.89 (Other diphtheritic complications) only when documentation doesn't support a more specific option: diphtheritic cardiomyopathy (A36.81), diphtheritic radiculomyelitis (A36.82), diphtheritic polyneuritis (A36.83), diphtheritic tubulo-interstitial nephropathy (A36.84), diphtheritic cystitis (A36.85) and diphtheritic conjunctivitis (A36.86).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC, relative weight 2.1859), DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC, relative weight 1.0235) and DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC, relative weight 0.6787), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about diphtheritic peritonitis ICD-10 codes
What is the ICD-10 code for diphtheritic peritonitis?
- A36.89 — Other diphtheritic complications.
Is A36.89 billable?
- Yes. A36.89 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A36.89 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A36.89 as a principal diagnosis.
Is A36.89 a CC or MCC?
- A36.89 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.