2027 ICD-10-CM Diagnosis Code B83.1Gnathostomiasis

ICD-10-CM Codes›A00–B99›B65-B83›B83

ICD-10-CM B83.1
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

B83.1 is a billable ICD-10-CM diagnosis code for gnathostomiasis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 867 through 869. Coders also document this condition as cerebral gnathostomiasis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Parasitic, other specified and unspecified infections.

Code Identity

ICD-10-CM Code
B83.1
Billable Status
Yes — Valid for Submission
Code Describes
Gnathostomiasis
Short Description
Gnathostomiasis
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 CodeB83.1Gnathostomiasis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cerebral gnathostomiasis
  • Cerebrospinal nematodiasis
  • Infection by Gnathostoma
  • Infection by Gnathostoma doloresi
  • Infection by Gnathostoma nipponicum
  • Infection by Gnathostoma spinigerum
  • Infection caused by Gnathostoma hispidum
  • Larval gnathostomiasis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to B83.1: its own notes plus those printed at B83 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Wandering swelling

Excludes1

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

From B83 Other helminthiases applies to 7 codes
  • capillariasis NOS (B81.1)

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 B83 Other helminthiases applies to 7 codes
  • intestinal capillariasis (B81.1)
From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name B83.1, its category, or a range that includes it.

Code First 1

These codes say to code first a condition named in the note, and B83.1 is one of the conditions named.

  • K67 Disorders of peritoneum in infectious diseases classified elsewhere
    helminthiasis (B65.0 -B83.9) names B65.0 -B83.9, 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 INF009
Parasitic, other specified and unspecified infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Gnathostomiasis

    infections with nematodes of the genus gnathostoma, superfamily thelazioidea. gnathostomiasis is a food-borne zoonosis caused by eating undercooked or raw fish or meat.

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 B83.1 to ICD-9-CMHistory

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

ICD-9-CM
128.1 Gnathostomiasis
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 B83.1Overview

What is the ICD-10 code for gnathostomiasis?

The ICD-10-CM code for gnathostomiasis is B83.1 (sometimes written as B831). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is B83.1 (Other helminthiases) a billable code?

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

What MS-DRG does B83.1 group to?

When gnathostomiasis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 867, 869, 868, with relative weights from 0.6784 to 2.1855 depending on complications. Higher weights mean higher Medicare reimbursement.

Can B83.1 be reported with B81.1?

Not as a rule. The Excludes1 note at B83, which applies to B83.1, lists "capillariasis NOS (B81.1)". 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).

What is the ICD-9 equivalent of B83.1?

Under the General Equivalence Mappings, gnathostomiasis converts to ICD-9-CM 128.1 (gnathostomiasis). The mapping is a direct match.