2026 ICD-10-CM Diagnosis Code B83.4Internal hirudiniasis

ICD-10-CM Codes›A00–B99›B65-B83›B83

ICD-10-CM B83.4
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

B83.4 is a billable ICD-10-CM diagnosis code for internal hirudiniasis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 606 through 607. Coders also document this condition as disease caused by Annelida. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Parasitic, other specified and unspecified infections.

Code Identity

ICD-10-CM Code
B83.4
Billable Status
Yes — Valid for Submission
Code Describes
Internal hirudiniasis
Short Description
Internal hirudiniasis
Same as the full description in the CMS dataset.
Parent Code
B83
Other helminthiases

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB65-B83Helminthiases
CategoryB83Other helminthiases
This CodeB83.4Internal hirudiniasis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Disease caused by Annelida
  • Internal hirudiniasis
  • Leech infestation

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Type 2 Excludes

  • external hirudiniasis B88.3

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Hirudiniasis
      • internal
    • Infestation
      • helminth
        • hirudiniasis, internal

Clinical ClassificationClinical

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

CCSR INF009
Parasitic, other specified and unspecified infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Parasitic Diseases

Parasites are living things that use other living things - like your body - for food and a place to live. You can get them from contaminated food or water, a bug bite, or sexual contact. Some parasitic diseases are easily treated and some are not.

Read the full article at MedlinePlus

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

Convert B83.4 to ICD-9-CMHistory

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

ICD-9-CM
134.2 Hirudiniasis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About B83.4Overview

Is B83.4 (Other helminthiases) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report internal hirudiniasis on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does B83.4 group to?

When internal hirudiniasis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 606, 607, with relative weights from 0.9064 to 1.5132 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of B83.4?

Under the General Equivalence Mappings, internal hirudiniasis converts to ICD-9-CM 134.2 (hirudiniasis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.