How Do I Code Pneumonia? Organism, Influenza First, Aspiration, and Ventilator-Associated

Chapter 10 files pneumonia by cause: J13 Streptococcus pneumoniae, J14 Hemophilus influenzae, J15.- other bacterial (J15.9 unspecified bacterial, inclusion “Pneumonia due to gram-positive bacteria”), J12.- viral, and J18.9, Pneumonia, unspecified organism, for the record that names none. Section I.B.18’s pneumonia example is exactly this: “a diagnosis of pneumonia has been determined, but not the specific type.”

Categories J12 through J16 and J18 carry a Code First note for associated influenza (J09.X1, J10.0-, J11.0-) that puts a documented influenza ahead of the pneumonia; J17, Pneumonia in diseases classified elsewhere, has a Code First note for the underlying disease instead. J13 through J17 carry a Code Also note — “if applicable, any associated condition such as: abscess (J85.1), aspiration pneumonia (J69.-)” — that asks for those codes without fixing their order; J12’s Code Also names only the abscess (J85.1), and J18’s only aspiration pneumonia (J69.-). Category J69 carries the matching note in the other direction: “Code also, if applicable, other types of pneumonias, such as: bacterial pneumonia (J13-J15.-), viral pneumonia (J12.-).” J18 also carries Excludes1 notes sending interstitial pneumonia NOS to J84.9 and drug-induced interstitial disease to J70.2–J70.4.

Two special cases have their own rules. J44.0, COPD with (acute) lower respiratory infection, carries “Code also to identify the infection” — the pneumonia code accompanies it. And ventilator-associated pneumonia is governed by Section I.C.10.d: “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.”

1. Organism documented? Code the category for it. Bacterial pneumonia with the organism named but not classified in J13–J15’s specific codes takes the B95/B96 organism code as the Use Additional Code — Section I.B.7’s own example. No organism → J18.9.
2. Influenza documented? Sequence it first under the Code First note. Section I.C.10.c: J09 and J10 only for confirmed identified influenza (confirmation is the provider’s statement, not a lab result); “suspected,” “possible” or “probable” identified influenza is coded to J11.
3. Aspiration documented?J69.0 (inclusion term “Aspiration pneumonia NOS”) is a Code Also partner, sequenced by the circumstances.
4. COPD patient? J44.0 plus the pneumonia code, per J44.0’s Code Also note.
5. On a ventilator? J95.851 only when the provider writes “ventilator-associated pneumonia”; add the B95–B97 organism code; do not add J12–J18. A pneumonia in a ventilated patient without that statement is coded as pneumonia; when unclear, query (I.C.10.d.1). A pneumonia present on admission that is later followed by VAP takes both codes (I.C.10.d.2).
6. “Probable pneumonia” follows the setting rule — coded as established on an inpatient discharge (II.H), coded to the symptoms in the office (IV.H). The symptom guide linked below walks it.

1. Community-acquired pneumonia, organism not identified.J18.9.
2. Pneumonia due to MRSA.J15.212 is the specific MRSA pneumonia code where the tabular provides one; where a bacterial pneumonia code lacks the organism, the pneumonia code is followed by the B95/B96 organism code — the I.B.7 pattern.
3. Influenza A (identified, not novel) with pneumonia. The J10.0- influenza-with-pneumonia code first, then the pneumonia code, per the Code First note.
4. Ventilated ICU patient; provider documents “VAP due to Pseudomonas.”J95.851 → B96.5. No J15 code.
5. COPD patient admitted with pneumococcal pneumonia.J44.0 and J13, sequenced by the reason for admission; J44.0’s Code Also asks for the infection.

• J95.851 for any pneumonia on a ventilator — only with the provider’s VAP statement.
• Adding J12–J18 to J95.851 — the guideline forbids it; the organism goes on a B code.
• Sequencing pneumonia before a documented influenza — the Code First note orders it.
• J09/J10 for “probable flu” — J11 unless the provider’s statement confirms the identified virus.
• J18.9 when the organism is documented — the specific category or the B95/B96 addition applies.

• The organism, and whether it is named as the cause.
• A documented influenza, and whether it is confirmed as an identified virus (J09/J10) or suspected (J11).
• Aspiration, abscess, or COPD, each bringing its own code.
• The provider’s explicit statement of ventilator-associated pneumonia.
• “Probable” or “suspected,” which the setting rules handle differently.