What is the ICD‑10‑CM code for Helicobacter pylori infection?

ICD-10-CM Code for Helicobacter pylori Infection

The ICD-10-CM code for Helicobacter pylori infection is B96.81. 1, 2

Primary Diagnosis Code

• B96.81 is the specific ICD-10-CM code that identifies Helicobacter pylori as the cause of diseases classified elsewhere. 1, 2
• This code achieved a positive predictive value of 100% when documented in inpatient encounters and 97.4% in outpatient encounters in validation studies. 1

Clinical Context for Code Selection

When coding for H. pylori-related conditions, the underlying disease manifestation should be coded first, followed by B96.81 as a secondary code to specify the causative organism:

• K27.9 (peptic ulcer, unspecified, without hemorrhage or perforation) should be the primary code when H. pylori causes peptic ulcer disease, with B96.81 as secondary. 3
• K29.70 (gastritis, unspecified, without bleeding) serves as the primary code for H. pylori-associated gastritis, followed by B96.81. 3
• K31.89 (other diseases of stomach and duodenum) applies when H. pylori causes broader gastric pathology not otherwise specified. 3

Documentation Requirements for Accurate Coding

The strongest predictors for validated H. pylori diagnosis in administrative data include:

• Outpatient ICD-9 code 041.86 (the ICD-9 equivalent, now B96.81 in ICD-10) with an odds ratio of 8.1. 1
• Eradication drug therapy (triple or quadruple therapy) with an odds ratio of 7.4. 1
• Esophagogastroduodenoscopy procedure with an odds ratio of 3.5. 1
• Age ≥70 years with an odds ratio of 1.2. 1

High-Risk Prevention Coding

• Z80.0 (family history of malignant neoplasm of digestive organs) should be used to justify H. pylori testing and treatment in patients with familial gastric cancer risk, as H. pylori is causally linked to 71-95% of all gastric cancers. 3, 4

Common Coding Pitfalls to Avoid

• Do not use serology test results alone to assign B96.81, as serological tests cannot distinguish active infection from past exposure and have only 78% accuracy. 5
• Document the original indication for H. pylori therapy (peptic ulcer, gastritis, dyspepsia, cancer prevention) in the medical record to substantiate the diagnosis code, as this is emphasized in coding validation studies. 3, 1
• Ensure diagnostic confirmation through validated methods—urea breath test (sensitivity 94.7-97%, specificity 95-100%) or monoclonal stool antigen test (sensitivity and specificity >90%)—before assigning B96.81. 3, 5

Algorithm for Code Assignment

When a patient presents with H. pylori-related disease:

1. Identify the primary gastroduodenal manifestation (ulcer, gastritis, dyspepsia, cancer risk) and assign the appropriate K-code.
2. Confirm active H. pylori infection through validated testing (not serology alone).
3. Assign B96.81 as a secondary code to specify H. pylori as the causative organism.
4. Add Z80.0 if family history of gastric cancer is present and influences management.
5. Document eradication therapy if prescribed, as this strengthens the validity of the B96.81 code assignment with a positive predictive value of 73.7% for triple therapy and 97.7% for quadruple therapy. 1