Q99.9

Chromosomal abnormality, unspecified

Billable FY2026 2025-10-01 → 2026-09-30

This is the unspecified option. 4 more specific codes sit alongside it. Worth checking whether the documentation supports one of them.

Exclusions 1 never code together

Excludes2

Excludes2 — not included here, but the patient may have both. Code both when documented.

Instructional notes

No further instructional notes apply.

Index entries leading here 3

Abnormal, abnormality, abnormalities — see also Anomaly
- autosomes Q99.9
- chromosome, chromosomal Q99.9
Anomaly, anomalous (congenital) (unspecified type) Q89.9
- chromosomes, chromosomal Q99.9
Syndrome — see also Disease
- due to abnormality
  - chromosomal Q99.9

Alongside this code 4 same parent — Q99

Additional references

AHA Coding Clinic® Licence required

Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.

Maps to no condition category in any loaded model.

Presence is a property of the code. Untick a model to hide it everywhere.

Present FY2024–FY2027.