ICD-10 E05.31
Billable / Specific MCCThyrotoxicosis from ectopic thyroid tissue with thyrotoxic crisis or storm
About ICD-10-CM E05.31
ICD-10-CM code E05.31 represents Thyrotoxicosis from ectopic thyroid tissue with thyrotoxic crisis or storm. This is a billable/specific code in the Endocrine, Nutritional, and Metabolic chapter (block E05). The 2026 edition of ICD-10-CM E05.31 became effective on October 1, 2025.
Coding Tips for E05.31
Specialist guidance from the PayerReady Medical Coding Team. Specificity warnings, HCC capture rules, sequencing notes.
E05.31 is designated MCC for MS-DRG grouping. On inpatient claims, this code can shift the DRG to the with-MCC variant when documented as a present-on-admission secondary diagnosis. Hospital CDI programs flag MCC opportunities during chart review. Failure to capture this code may leave 30 to 80 percent of the inpatient stay revenue unrealized.
Inpatient DRG Impact, MCC
codes Thyrotoxicosis from ectopic thyroid tissue with thyrotoxic crisis or storm. As a Major Complication/Comorbidity (MCC), this can shift the DRG assignment to a higher-weighted category, substantial reimbursement impact.
Medicare LCD Coverage for E05.31
Local Coverage Determinations (LCDs) from CMS MACs that list E05.31 as a covered diagnosis.
Showing top 10 of 91 total . Click a CPT for full coverage scope.
Commercial Payer Coverage
Coverage policies from major commercial payers referencing E05.31.
5 Medicare
CPT Codes Commonly Billed with E05.31
Procedures frequently paired with this diagnosis based on PayerReady's Dx↔Px linkage data.
- 83735 CMS LCD: Billing and Coding: Magnesium CMS LCD
- 76536 CMS LCD: Billing and Coding: Ultrasound, Soft Tissues of Head and Neck CMS LCD
- 01782 CMS LCD: Billing and Coding: Monitored Anesthesia Care CMS LCD
- 01999 CMS LCD: Billing and Coding: Monitored Anesthesia Care CMS LCD
- 01829 CMS LCD: Billing and Coding: Monitored Anesthesia Care CMS LCD
- 00400 CMS LCD: Billing and Coding: Monitored Anesthesia Care CMS LCD
- 01922 CMS LCD: Billing and Coding: Monitored Anesthesia Care CMS LCD
- 00731 CMS LCD: Billing and Coding: Monitored Anesthesia Care CMS LCD
- 00635 CMS LCD: Billing and Coding: Monitored Anesthesia Care CMS LCD
- 00322 CMS LCD: Billing and Coding: Monitored Anesthesia Care CMS LCD
Convert E05.31 to ICD-9-CM
Per CMS General Equivalence Mappings (GEMs), useful for legacy data review and historical claim analysis.
| ICD-10 | ICD-9 | Mapping Flags |
|---|---|---|
| E05.31 | 24241 | 00000 |
Flags format (5 digits): Approximate · No Map · Combination · Scenario · Choice List. Source: CMS 2017 GEMs (final version).
Codes Adjacent To E05.31
Other codes in section E00-E07 (Disorders of thyroid gland).
ICD-10 E05.31, Billing FAQ
Is ICD-10 code E05.31 billable? +
Yes, E05.31 is a billable ICD-10-CM code that can appear as a primary or secondary diagnosis on claims.
Is E05.31 a CC or MCC for inpatient DRG? +
Yes, this code is designated as MCC. Documenting as a secondary diagnosis on inpatient claims can shift the DRG to a higher-weighted category.
What CPT codes are commonly billed with E05.31? +
Procedures frequently paired with E05.31 include: 83735, 76536, 01782, 01999, 01829.
What ICD-9 codes does E05.31 map to? +
Per CMS GEMs, E05.31 maps to ICD-9 codes: 24241. Useful for legacy data review and historical claim analysis.
Get the full PayerReady toolkit
Free access to CPT/ICD-10 lookup, denial appeals, fee comparator, and claim auditing with credentialing enrollment.
Start free →Run this code through our claim audit tool
Check NCCI bundling, MUE limits, and modifier logic before submission.
Try the auditor →Did this page help?
Quick signal so we know what to improve.
If you want a code reference page that doesn't exist yet, email coding@payerready.com.
Tell us what's missing or wrong: coding@payerready.com. We respond within 5 business days.
Reviewed by the PayerReady Medical Coding Team
Verified against the CMS 2026 code set on May 31, 2026.
Powered by 11K CPT · 98K ICD-10 · 860K MPFS rates · 4.5M NCCI edits · 9.5M NPIs. Our data methodology · About our coding team