Q56 vs Q99
Q56 (Indeterminate sex and pseudohermaphroditism) compared with Q99 (Other chromosome abnormalities, not elsewhere classified), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. Q56 carries an Excludes1 note covering Q99: “pseudohermaphroditism with specified chromosomal anomaly (Q96-Q99)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
No — do not report together. Q56 carries an Excludes1 note covering Q99: “syndromes associated with anomalies in the number and form of chromosomes (Q90-Q99)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| Q56Indeterminate sex and pseudohermaphroditism | Q99Other chromosome abnormalities, not elsewhere classified | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | Q00-Q99 — Congenital Malformations, Deformations and Chromosomal Abnormalities (Q00-Q99) | Q00-Q99 — Congenital Malformations, Deformations and Chromosomal Abnormalities (Q00-Q99) |
| Definition | Indeterminate sex and pseudohermaphroditism is a non-billable ICD-10-CM category code (Q56). | Other chromosome abnormalities, not elsewhere classified is a non-billable ICD-10-CM category code (Q99). |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources