E05.91 — Thyrotoxicosis, unspecified with thyrotoxic crisis or storm
Is E05.91 billable?
Yes, but E05.91 is an unspecified code. E05.91 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, E05.91 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting E05.91 — the more specific alternatives are listed below.
More specific alternatives
E05.91 at a glance
| Code | E05.91 |
|---|---|
| Description | Thyrotoxicosis, unspecified with thyrotoxic crisis or storm |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does E05.91 group to?
E05.91 sits in MDC Pre and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 011Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCCsurgical
- 012Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CCsurgical
- 013Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCCsurgical
As a secondary diagnosis, E05.91 is a major complication or comorbidity (MCC), which can move a stay into a higher-paying DRG.
How is E05.91 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to E05.91. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Cardiomyopathy › thyrotoxic › with thyroid storm (familial) (idiopathic)
- Hyperthyroidism › with › storm (latent) (pre-adult) (recurrent)
- Myocardiopathy › thyrotoxic › with storm (congestive) (constrictive) (familial) (hypertrophic nonobstructive) (idiopathic) (infiltrative) (obstructive) (primary) (restrictive) (sporadic)
- Myxedema › circumscribed › with storm (adult) (idiocy) (infantile) (juvenile)
- Myxedema › localized › with storm (adult) (idiocy) (infantile) (juvenile)
- Thyrotoxic › heart disease or failure › with thyroid storm
- Thyrotoxicosis › with › thyroid storm (recurrent)
- Thyrotoxicosis › heart › with thyroid storm (recurrent)
- Cardiomyopathy › metabolic › thyrotoxic › with thyroid storm (familial) (idiopathic)
- Chloasma › eyelid › hyperthyroid › with thyroid storm (skin) (idiopathic) (symptomatic)
- Disease, diseased › heart › hyperthyroid › with thyroid storm
- Disease, diseased › heart › thyrotoxic › with thyroid storm
Excludes1 — never code together — inherited from Chapter 4
The conditions below can never be reported together with E05.91 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- transitory endocrine and metabolic disorders specific to newborn (P70-P74)
Excludes1 — never code together — inherited from E05
The conditions below can never be reported together with E05.91 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
How long has E05.91 existed?
E05.91 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.