P81.9 Disturbance of temperature regulation of newborn, unspecified

Billable ICD-10-CM code, FY2026.

Applicable to

• Fever of newborn NOS

MS-DRG index

Defines the logic of DRG(s) 794 in MDC 15.

Approximate ICD-9-CM (GEMs)

• 778.4 Other disturbances of temperature regulation of newborn (approximate)

Code annotations containing back-references to P81.9

Back-references to P81.9

• Type 1 Excludes: R50 Fever of other and unknown origin ("fever of unknown origin in newborn (P81.9)")

Diagnosis Index entries for P81.9

• Disorder (of) › temperature regulation, newborn
• Disturbance (s) › temperature › regulation, newborn
• Fever (inanition) (of unknown origin) (persistent) (with chills) (with rigor) › newborn
• Hyperthermia (of unknown origin) › newborn
• Newborn (infant) (liveborn) (singleton) › fever
• Pyrexia (of unknown origin) › newborn

Nearby codes

• P81 Other disturbances of temperature regulation of newborn
• P81.0 Environmental hyperthermia of newborn
• P81.8 Other specified disturbances of temperature regulation of newborn
• P81.9 Disturbance of temperature regulation of newborn, unspecified (this code)