G91.4 vs P37.1
G91.4 (Hydrocephalus in diseases classified elsewhere) compared with P37.1 (Congenital toxoplasmosis), 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. G91.4 carries an Excludes1 note covering P37.1: “hydrocephalus due to congenital toxoplasmosis (P37.1)”
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
| G91.4Hydrocephalus in diseases classified elsewhere | P37.1Congenital toxoplasmosis | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | G00-G99 — Diseases of the Nervous System (G00-G99) | P00-P96 — Certain Conditions Originating in the Perinatal Period (P00-P96) |
| Definition | Hydrocephalus in diseases classified elsewhere is a billable ICD-10-CM diagnosis code (G91.4). | Congenital toxoplasmosis is a billable ICD-10-CM diagnosis code (P37.1). |
| Includes | acquired hydrocephalus | Hydrocephalus due to congenital toxoplasmosis |
| Code first | underlying condition, such as: congenital syphilis (A50.4-) | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources