B26.84 ICD-10-CM Code: Mumps polyneuropathy
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Coding at a Glance
- Tabular directives
- 2 inclusion terms
Inpatient Payment Groups (MS-DRG)
Potential MS-DRG participation — not a DRG assignment.
MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43, Appendix B.
- MS-DRG 073 — CRANIAL AND PERIPHERAL NERVE DISORDERS WITH MCC (MDC 01)
- MS-DRG 074 — CRANIAL AND PERIPHERAL NERVE DISORDERS WITHOUT MCC (MDC 01)
- MS-DRG 791 — PREMATURITY WITH MAJOR PROBLEMS (MDC 15)
- MS-DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)
A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.
Coding instructions
Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for B26.84 in the official ICD-10-CM tabular list, quoted as published.
Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025
Notes without a marker are published on B26.84 itself; “inherited from” names the category or block whose note applies here.
Includes
Conditions the official ICD-10-CM tabular list includes under this code.
- epidemic parotitis
- infectious parotitis
Source: inherited from B26
Code Overview
MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.
Indexed Clinical Terms (2)
Official source data — entries quoted as published, in the Index’s own lookup phrasing
Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.
Verify Before Coding
- CC as a secondary diagnosis (FY2026). Can raise the stay's MS-DRG severity tier.
From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.
Relationships & Classification
MedCoder structured relationships — computed from published CMS and AHRQ datasets
Other codes that name B26.84 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.
Referenced by 2 Excludes1 notes across 2 chapters: G63 — Polyneuropathy in diseases classified elsewhere, K11.2 — Sialoadenitis (via B26.-).
These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.
Referenced by 1 Code First instruction: H67 — Otitis media in diseases classified elsewhere (via B26.-).
Each of these codes carries a Code First note naming this condition — when that code is reported, THIS code is sequenced first, ahead of it.
MS-DRG Grouper Relationships (FY2026)
Potential MS-DRG participation — not a DRG assignment.
FY2026 MS-DRG: CC — Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 23 clinically related codes on its CMS exclusion list.
Named in the grouper logic of 4 MS-DRGs: DRG 073 (MDC 01), DRG 074 (MDC 01), DRG 791 (MDC 15), DRG 793 (MDC 15).
From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.
Clinical classification (AHRQ CCSR):NVS015 — Polyneuropathies (default); INF008 — Viral infection.
Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.
Related Codes
Same clinical process (MS-DRG)
Acts as CC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.
A74.81 — Chlamydial peritonitis, A74.89 — Other chlamydial diseases, A74.9 — Chlamydial infection, unspecified, A96.2 — Lassa fever, A98.3 — Marburg virus disease, A98.4 — Ebola virus disease, B26.82 — Mumps myocarditis, B26.83 — Mumps nephritis, B26.85 — Mumps arthritis, B26.89 — Other mumps complications, B26.9 — Mumps without complication, B33.24 — Viral cardiomyopathy, B33.4 — Hantavirus (cardio)-pulmonary syndrome [HPS] [HCPS], B33.8 — Other specified viral diseases, B34.1 — Enterovirus infection, unspecified, B34.2 — Coronavirus infection, unspecified, B34.4 — Papovavirus infection, unspecified, B34.8 — Other viral infections of unspecified site, B92 — Sequelae of leprosy, B94.2 — Sequelae of viral hepatitis, +2 more
Same clinical category (CCSR)
AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (Polyneuropathies, Viral infection).
A36.83 — Diphtheritic polyneuritis, A50.43 — Late congenital syphilitic polyneuropathy, A52.15 — Late syphilitic neuropathy, B02.23 — Postherpetic polyneuropathy, B27.01 — Gammaherpesviral mononucleosis with polyneuropathy, B27.11 — Cytomegaloviral mononucleosis with polyneuropathy, B27.81 — Other infectious mononucleosis with polyneuropathy, B27.91 — Infectious mononucleosis, unspecified with polyneuropathy, E08.42 — Diabetes mellitus due to underlying condition with diabetic polyneuropathy, E08.43 — Diabetes mellitus due to underlying condition with diabetic autonomic (poly)neuropathy, E09.42 — Drug or chemical induced diabetes mellitus with neurological complications with diabetic polyneuropathy, E09.43 — Drug or chemical induced diabetes mellitus with neurological complications with diabetic autonomic (poly)neuropathy, E10.42 — Type 1 diabetes mellitus with diabetic polyneuropathy, E10.43 — Type 1 diabetes mellitus with diabetic autonomic (poly)neuropathy, E11.42 — Type 2 diabetes mellitus with diabetic polyneuropathy, E11.43 — Type 2 diabetes mellitus with diabetic autonomic (poly)neuropathy, E13.42 — Other specified diabetes mellitus with diabetic polyneuropathy, E13.43 — Other specified diabetes mellitus with diabetic autonomic (poly)neuropathy, G60.0 — Hereditary motor and sensory neuropathy, G60.1 — Refsum's disease, +346 more
Same Index main term, other category
The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Polyneuropathy”; these codes share that main term but sit in a different category of the Tabular List.
A17.89 — Other tuberculosis of nervous system (in, tuberculosis), A30.9 — Leprosy, unspecified (in, leprosy), A36.83 — Diphtheritic polyneuritis (in, diphtheria), A50.43 — Late congenital syphilitic polyneuropathy (syphilitic, congenital), A52.15 — Late syphilitic neuropathy (syphilitic), A69.22 — Other neurologic disorders in Lyme disease (in, Lyme disease), B02.23 — Postherpetic polyneuropathy (in, zoster), B27.91 — Infectious mononucleosis, unspecified with polyneuropathy (in, infectious, mononucleosis), B89 — Unspecified parasitic disease (in, parasitic disease NEC), B99 — Other and unspecified infectious diseases (in, infectious, disease NEC), D49.9 — Neoplasm of unspecified behavior of unspecified site (in, neoplastic disease), D51.0 — Vitamin B12 deficiency anemia due to intrinsic factor deficiency (in, vitamin B12 deficiency, with anemia), D51.3 — Other dietary vitamin B12 deficiency anemia (in, vitamin B12 deficiency, with anemia, due to dietary deficiency), D86.89 — Sarcoidosis of other sites (in, sarcoidosis), E16.2 — Hypoglycemia, unspecified (in, hypoglycemia), E34.9 — Endocrine disorder, unspecified (in, endocrine disease NEC), E51.11 — Dry beriberi (in, beriberi), E52 — Niacin deficiency [pellagra] (in, pellagra), E53.1 — Pyridoxine deficiency (in, deficiency, vitamin B6), E53.8 — Deficiency of other specified B group vitamins (in, vitamin B12 deficiency), +27 more
Contextual Map
Every relationship of B26.84 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.
Run B26.84 with these 3 related codes in Claim Check
Hierarchy
- A00-B99 — Chapter 1: Certain Infectious and Parasitic Diseases (A00-B99) (A00-B99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B25-B34 — Other viral diseases[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
Referenced by Excludes1 notes
- G63 — Polyneuropathy in diseases classified elsewhere[Excludes1]: “mumps (B26.84)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
- K11.2 — Sialoadenitis[Excludes1](via B26.-): “epidemic parotitis (B26.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Referenced by Code First instructions
- H67 — Otitis media in diseases classified elsewhere[Code First](via B26.-): “viral disease NEC (B00-B34)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
Clinical classification (CCSR)
- NVS015 — Polyneuropathies[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)
- INF008 — Viral infection[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)
MS-DRG Grouper
- CC — Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (CC).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2026
- DRG 073 — CRANIAL AND PERIPHERAL NERVE DISORDERS WITH MCC[MS-DRG]: “CRANIAL AND PERIPHERAL NERVE DISORDERS WITH MCC (MDC 01)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
- DRG 074 — CRANIAL AND PERIPHERAL NERVE DISORDERS WITHOUT MCC[MS-DRG]: “CRANIAL AND PERIPHERAL NERVE DISORDERS WITHOUT MCC (MDC 01)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
- DRG 791 — PREMATURITY WITH MAJOR PROBLEMS[MS-DRG]: “PREMATURITY WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
- DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS[MS-DRG]: “FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
MDC crossing
- MDC 01 — Diseases and Disorders of the Nervous System[MDC crossing]: “Diseases and Disorders of the Nervous System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 8,892 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026
- MDC 15 — Newborns and Other Neonates with Conditions Originating in Perinatal Period[MDC crossing]: “Newborns and Other Neonates with Conditions Originating in Perinatal Period — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs.”— CMS MS-DRG Definitions Manual · FY2026
Index entries
- Mumps, polyneuropathy[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
- Polyneuropathy (peripheral), in (due to), mumps[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
Nearest codes (12)
- B26 — Mumps[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B26.0 — Mumps orchitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B26.1 — Mumps meningitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B26.2 — Mumps encephalitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B26.3 — Mumps pancreatitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B26.8 — Mumps with other complications[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B26.81 — Mumps hepatitis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- B26.82 — Mumps myocarditis[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
- and 4 more
Change history
- FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016
Sources for this page
Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.
- Code, title, tabular notes and index terms Official source data
- CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
- Claim edits Official source data
- CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
- Inpatient payment groups Official source data
- CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page
- Change history and date-of-service validity Official source data
- CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
- Comparisons, relationships and the contextual map MedCoder structured relationship
- Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
- Summary and FAQ answers MedCoder explanation
- Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.
Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates
Cite this page
Reference this page in a research guide, syllabus or article. The release is included because code content changes each year.
MedCoder.ai. "B26.84 — Mumps polyneuropathy." ICD-10-CM FY2026. https://medcoder.ai/icd10/code/b26.84-mumps-polyneuropathy
Change history
- FY2016 — October 1, 2015In the code set at ICD-10-CM adoptionMumps polyneuropathy
No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.
Nearest Codes in This Family
Official ICD-10-CM classifications closest to B26.84 in its code family, with their registry titles.