2027 ICD-10-CM Diagnosis Code E87.4Mixed disorder of acid-base balance

ICD-10-CM Codes›E00–E89›E70-E88›E87

ICD-10-CM E87.4
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

E87.4 is a billable ICD-10-CM diagnosis code for mixed disorder of acid-base balance. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 640 through 641, 791, 793. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 17 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fluid and electrolyte disorders.

Code Identity

ICD-10-CM Code
E87.4
Billable Status
Yes — Valid for Submission
Code Describes
Mixed disorder of acid-base balance
Short Description
Mixed disorder of acid-base balance
Same as the full description in the CMS dataset.
Parent Code
E87
Other disorders of fluid, electrolyte and acid-base balance

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE70-E88Metabolic disorders
CategoryE87Other disorders of fluid, electrolyte and acid-base balance
This CodeE87.4Mixed disorder of acid-base balance

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Abnormal acid-base balance
  • Abnormal acid-base balance affecting management of mother
  • Acid-base balance - finding
  • Base deficit
  • Base excess
  • Hypercapnia
  • Hypercapnia with mixed acid-base disorder
  • Metabolic acidosis and metabolic alkalosis
  • Mixed acid-base balance disorder
  • Mixed acid-base balance disorders - not compensated primary disorder
  • Respiratory acidosis and metabolic acidosis
  • Respiratory acidosis and metabolic alkalosis
  • Respiratory alkalosis and metabolic acidosis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to E87.4: its own notes plus those printed at E87, block E70-E88, and Chapter 4. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From E87 Other disorders of fluid, electrolyte and acid-base balance applies to 14 codes
  • diabetes insipidus (E23.2)
  • electrolyte imbalance associated with hyperemesis gravidarum (O21.1)
  • electrolyte imbalance following ectopic or molar pregnancy (O08.5)
  • familial periodic paralysis (G72.3)
  • metabolic acidemia in newborn, unspecified (P19.9)
From Block E70-E88 Metabolic disorders applies to 286 codes
  • androgen insensitivity syndrome (E34.5-)
  • congenital adrenal hyperplasia (E25.0)
  • hemolytic anemias attributable to enzyme disorders (D55.-)
  • Marfan syndrome (Q87.4-)
  • 5-alpha-reductase deficiency (E29.1)
From Chapter 4 (E00-E89) Endocrine, nutritional and metabolic diseases applies to 973 codes
  • transitory endocrine and metabolic disorders specific to newborn (P70-P74)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Block E70-E88 Metabolic disorders applies to 286 codes
  • Ehlers-Danlos syndromes (Q79.6-)

Notes

General instructions on how these codes are used.

From Chapter 4 (E00-E89) Endocrine, nutritional and metabolic diseases applies to 973 codes
  • All neoplasms, whether functionally active or not, are classified in Chapter 2. Appropriate codes in this chapter (i.e. E05.8, E07.0, E16-E31, E34.-) may be used as additional codes to indicate either functional activity by neoplasms and ectopic endocrine tissue or hyperfunction and hypofunction of endocrine glands associated with neoplasms and other conditions classified elsewhere.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name E87.4, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming E87.4: its condition is not part of those codes, and both may be reported when the patient has both.

  • R79.1 Abnormal coagulation profile
    abnormality of fluid, electrolyte or acid-base balance (E86-E87) names E86-E87, which includes this code
  • Block T80-T88 Complications of surgical and medical care, not elsewhere classified
    disorders of fluid and electrolyte imbalance (E86-E87) names E86-E87, which includes this code

Use Additional Code 1

These codes say to use an additional code from the note, and E87.4 is one of the codes named.

  • E86 Volume depletion
    code(s) for any associated disorders of electrolyte and acid-base balance (E87.-) names E87.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR END011
Fluid and electrolyte disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Fluid and Electrolyte Balance

Electrolytes are minerals that have an electric charge when they are dissolved in water or body fluids, including blood. The electric charge can be positive or negative. You have electrolytes in your blood, urine (pee), tissues, and other body fluids.

The full article covers:

  • What are electrolytes?
  • What are the different types of electrolytes in your body?
  • What is an electrolyte imbalance?
  • What are the different types of electrolyte imbalances?
  • How are electrolyte imbalances diagnosed?
  • What are the treatments for electrolyte imbalances?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert E87.4 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
276.4 Mixed acid-base bal dis
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About E87.4Overview

What is the ICD-10 code for mixed disorder of acid-base balance?

The ICD-10-CM code for mixed disorder of acid-base balance is E87.4 (sometimes written as E874). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is E87.4 (Other disorders of fluid, electrolyte and acid-base balance) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report mixed disorder of acid-base balance on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does E87.4 group to?

When mixed disorder of acid-base balance is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 641, 640, with relative weights from 0.7864 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.

Is E87.4 a CC or MCC?

CMS lists E87.4 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 17 closely related codes in its exclusion list.

Can E87.4 be reported with E23.2?

Not as a rule. The Excludes1 note at E87, which applies to E87.4, lists "diabetes insipidus (E23.2)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).