J18 Pneumonia, unspecified organism

The ICD-10-CM code for Pneumonia, unspecified organism is J18 (FY2026). It is a non-billable category code — select a more specific code below for claims.

Classification

Chapter

10: Diseases of the respiratory system (J00-J99)

Section

J09-J18: Influenza and pneumonia (J09-J18)

Category J18

6 codes (5 billable)

FY2026 Status

Stable since FY2024

Official Coding Guidelines

VAP: assign J95.851 only with provider documentation; add organism code

d. Ventilator associated Pneumonia 1) Documentation of Ventilator associated Pneumonia As with all procedural or postprocedural complications, code assignment is based on the provider’s documentation of the relationship between the condition and the procedure. Code J95.851, Ventilator associated pneumonia, should be assigned only when the provider has documented ventilator associated pneumonia (VAP). An additional code to identify the organism (e.g., Pseudomonas aeruginosa, code B96.5) should also be assigned. Do not assign an additional code from categories J12-J18 to identify the type of pneumonia. Code J95.851 should not be assigned for cases where the patient has pneumonia and is on a mechanical ventilator and the provider has not specifically stated that the pneumonia is ventilator-associated pneumonia. If the documentation is unclear as to whether the patient has a pneumonia that is a complication attributable to the mechanical ventilator, query the provider.

VAP develops after admission—principal dx vs additional dx

2) Ventilator associated Pneumonia Develops after Admission A patient may be admitted with one type of pneumonia (e.g., code J13, Pneumonia due to Streptococcus pneumonia) and subsequently develop VAP. In this instance, the principal diagnosis would be the appropriate code from categories J12-J18 for the pneumonia diagnosed at the time of admission. Code J95.851, Ventilator associated pneumonia, would be assigned as an additional diagnosis when the provider has also documented the presence of ventilator associated pneumonia.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool