Medical Coding Pneumonia

Pneumonia Coding & Billing – Guidelines & Tips

Pneumonia is a common and potentially serious respiratory infection that medical coders frequently encounter. Accurate coding and billing are essential to reflect the severity of illness, ensure compliance with payer rules, and support appropriate reimbursement.

Understanding Pneumonia

Pneumonia is an infection that inflames the air sacs in one or both lungs. It can be caused by bacteria, viruses, fungi, or other organisms. The cause, location, and severity influence both the diagnosis code selection and billing.

ICD-10-CM Coding for Pneumonia

Identify the Type and Cause

Pneumonia codes in ICD-10-CM fall under J12–J18:

• J12.0 – J12.9: Viral pneumonia (e.g., due to adenovirus, RSV)

• J13: Pneumonia due to Streptococcus pneumoniae

• J14: Pneumonia due to Haemophilus influenzae

• J15.0 – J15.9: Bacterial pneumonia (other specified bacteria)

• J16.0 – J16.9: Pneumonia due to other specified infectious organisms

• J17: Pneumonia in diseases classified elsewhere (use additional code for underlying condition)

• J18.0 – J18.9: Pneumonia, unspecified organism

Tip: Always review lab results, cultures, and provider documentation to identify the most specific organism.

Code Additional Conditions When Applicable

• COVID-19 Pneumonia: Use U07.1 and J12.82

• Influenza with Pneumonia: Use combination codes such as J09.X1, J10.0, or J11.0

• Aspiration Pneumonia: J69.0 (due to food/vomit) and other subcategories depending on substance

• Ventilator-Associated Pneumonia: J95.851

Documentation Must Include:

• Causative organism (if known)

• Type (bacterial, viral, fungal, aspiration, etc.)

• Laterality/lobar involvement (if documented)

• Whether hospital-acquired or community-acquired

• Associated conditions (e.g., sepsis, respiratory failure)

CPT/HCPCS Coding for Pneumonia-Related Services

Pneumonia coding often involves more than just the diagnosis:

• Office/Outpatient Visits: 99202–99215 (based on MDM or time)

• Hospital Inpatient/Observation Care: 99221–99233

• Imaging:

  • Chest X-ray – 71045–71048

  • Chest CT – 71250–71270

• Laboratory Tests:

  • Blood cultures – 87040

  • Respiratory pathogen panels – 87631–87633

• Procedures:

  • Thoracentesis (if pleural effusion present) – 32554, 32555

Billing Guidelines & Tips

1. Link ICD-10-CM codes to CPT/HCPCS codes to establish medical necessity.

2. Sequence appropriately – pneumonia may be the principal diagnosis for hospitalization unless sepsis or another more severe condition is present.

3. Avoid unspecified codes unless there is no documentation to support specificity.

4. Use Z codes for follow-up when patient is recovering and pneumonia has resolved (e.g., Z09 follow-up exam).

5. Check payer-specific requirements – some insurers require additional documentation for pneumonia admissions.

6. Apply modifiers when billing multiple related services (e.g., modifier 25 for E/M with procedure).

Common Coding Pitfalls

• Using J18.9 (unspecified pneumonia) when documentation supports specificity

• Forgetting to code complications like respiratory failure or sepsis

• Omitting secondary diagnoses that affect severity and DRG assignment

• Not updating the code if culture results return after initial coding

Key Takeaways

• Always code pneumonia to the highest level of specificity possible.

• Review lab and imaging results to support diagnosis coding.

• Ensure documentation clearly identifies the organism, type, and any complications.

• Follow payer rules to avoid denials and ensure proper reimbursement.

Read more Coding Clarified blogs on how to code topics and let Coding Clarified “clarify” coding for you! https://codingclarified.com/medical-coding-blog/

Coding Corner: Billing for Straightforward Pneumonia in a Hospitalized Patient https://www.the-hospitalist.org/hospitalist/article/36253/critical-care/coding-corner-billing-for-straightforward-pneumonia-in-a-hospitalized-patient/