A09
A09: Infectious gastroenteritis and colitis, unspecified
Billable / specific codeICD-10-CM
A09 is a billable, specific ICD-10-CM code for infectious gastroenteritis and colitis, unspecified. It is valid for submission on a claim.
Check A09 with the rest of the claim: free scrubberExcludes1: never code together
These conditions cannot occur together. Billing both on the same encounter is a denial.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Infectious colitis NOS
- Infectious enteritis NOS
- Infectious gastroenteritis NOS
Other codes that can never be billed with A09
Their own Excludes1 notes name this code, so the conflict is not listed above.
- K52.9Noninfective gastroenteritis and colitis, unspecified
Risk adjustment
No CMS-HCC V28 category: this code does not change a RAF score.
Medicare coverage
A09 is named in 10 Medicare coverage policies: 10 listing it as supporting medical necessity. Which one applies depends on your Medicare contractor.
- A55937Billing and Coding: Diagnostic Colonoscopy
- A56394Billing and Coding: Colonoscopy and Sigmoidoscopy-Diagnostic
- A56456Billing and Coding: Colonoscopy/Sigmoidoscopy/Proctosigmoidoscopy
- A56632Billing and Coding: Colonoscopy/Sigmoidoscopy/Proctosigmoidoscopy
Alphabetic index entries that lead here
- Dysentery, dysenteric(catarrhal) (diarrhea) (epidemic) (hemorrhagic) (infectious) (sporadic) (tropical)
- Diarrhea, diarrheal›dysenteric
- Diarrhea, diarrheal›endemic
- Diarrhea, diarrheal›epidemic
- Diarrhea, diarrheal›infectious
- Disease, diseased›diarrheal, infectious NEC
- Dysentery, dysenteric›arthritis
- Enteritis›epidemic(infectious)
- Enteritis›infectious NOS
- Enteritis›septic
- Enterocolitis›infectious NEC
- Gastroenteritis›epidemic(infectious)
Code history
Unchanged in every release from FY2024 to FY2027.