Q85.1 Tuberous sclerosis

The ICD-10-CM code for Tuberous sclerosis is Q85.1 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

17: Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0)

Section

Q80-Q89: Other congenital malformations (Q80-Q89)

Category Q85

14 codes (11 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to Q85.1:

• Pringle's disease (tuberous sclerosis)
• Tuberous sclerosis (brain)
• Neurospongioblastosis diffusa
• Bourneville's disease
• Epiloia
• Disease, diseased › Bourneville (-Brissaud) (tuberous sclerosis)
• Disease, diseased › Pringle's (tuberous sclerosis)
• Nevus › multiplex

Inclusion Terms

• Bourneville's disease
• Epiloia

U.S. Hospital Utilization

• An estimated 3,365 U.S. inpatient stays in 2023 included Q85.1 among the documented diagnoses.
• 205 stays listed it as the principal diagnosis.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

POA indicator for congenital conditions/anomalies and Q00-Q99 exception

Congenital conditions and anomalies Assign “Y” for congenital conditions and anomalies except for categories Q00- Q99, Congenital anomalies, which are on the exempt list. Congenital conditions are always considered present on admission.

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)