G90.1 Familial dysautonomia [Riley-Day]

Billable ICD-10-CM code, FY2026.

Applies from G90 Disorders of autonomic nervous system

Excludes1 (never code together)

• dysfunction of the autonomic nervous system due to alcohol (G31.2)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 182 — Spinal Cord Disorders/Injuries
• CMS-HCC V22: HCC 72 — Spinal Cord Disorders/Injuries
• RxHCC V08: HCC 155 — Spinal Cord Disorders
• ESRD V24: HCC 72

MS-DRG index

Defines the logic of DRG(s) 091-093 in MDC 01.

Approximate ICD-9-CM (GEMs)

• 742.8 Other specified congenital anomalies of nervous system (approximate)

Code annotations containing back-references to G90.1

Back-references to G90.1

• Type 2 Excludes: Q07 Other congenital malformations of nervous system ("familial dysautonomia [Riley-Day] (G90.1)")
• Type 1 Excludes: Q85 Phakomatoses, not elsewhere classified ("familial dysautonomia [Riley-Day] (G90.1)")

Diagnosis Index entries for G90.1

• Dysautonomia (familial)
• Riley-Day syndrome

Nearby codes

• G90 Disorders of autonomic nervous system
• G90.0 Idiopathic peripheral autonomic neuropathy
• G90.01 Carotid sinus syncope
• G90.09 Other idiopathic peripheral autonomic neuropathy
• G90.1 Familial dysautonomia [Riley-Day] (this code)
• G90.2 Horner's syndrome
• G90.3 Multi-system degeneration of the autonomic nervous system
• G90.4 Autonomic dysreflexia
• G90.5 Complex regional pain syndrome I (CRPS I)
• G90.50 Complex regional pain syndrome I, unspecified