Q33.9 — Congenital malformation of lung, unspecified
Is Q33.9 billable?
Yes, but Q33.9 is an unspecified code. Q33.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, Q33.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting Q33.9 — the more specific alternatives are listed below.
Q33.9 at a glance
| Code | Q33.9 |
|---|---|
| Description | Congenital malformation of lung, unspecified |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does Q33.9 group to?
Q33.9 sits in MDC 04 and helps define the logic of 2 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 205Other Respiratory System Diagnoses with MCCmedical
- 206Other Respiratory System Diagnoses without MCCmedical
How is Q33.9 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to Q33.9. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Anomaly, anomalous › lung (congenital) (unspecified type)
- Anomaly, anomalous › pulmonary (congenital) (unspecified type)
- Deformity › lung
- Malformation › lung (congenital)
- Disease, diseased › lung › congenital
Excludes2 — not included here — inherited from Chapter 17
The conditions below are not part of Q33.9, but a patient may have both at the same time. When documentation supports it, Q33.9 and the excluded code may both be reported.
- inborn errors of metabolism (E70-E88)
How long has Q33.9 existed?
Q33.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.