2026 ICD-10-CM Diagnosis Code A27.89Other forms of leptospirosis

ICD-10-CM Codes›A00–B99›A20-A28›A27

ICD-10-CM A27.89
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A27.89 is a billable ICD-10-CM diagnosis code for other forms of leptospirosis. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections.

Code Identity

ICD-10-CM Code
A27.89
Billable Status
Yes — Valid for Submission
Code Describes
Other forms of leptospirosis
Short Description
Other forms of leptospirosis
Same as the full description in the CMS dataset.
Parent Code
A27.8
Other forms of leptospirosis

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA20-A28Certain zoonotic bacterial diseases
CategoryA27Leptospirosis
This CodeA27.89Other forms of leptospirosis

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Canicola fever
  • Disease caused by Hantavirus
  • Fort Bragg Fever
  • Infection caused by Leptospira australis
  • Infection caused by Leptospira bataviae
  • Infection caused by Leptospira Grippotyphosa
  • Infection caused by Leptospira Pyrogenes
  • Infection caused by Orientia
  • Lepthangamushi syndrome
  • Leptospirosis with cutaneous involvement
  • Nanukayami
  • Puumala virus nephropathy
  • Scrub typhus
  • Uveitis due to leptospirosis

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.

    • Fever(inanition) (of unknown origin) (persistent) (with chills) (with rigor)
      • Fort Bragg
    • Fever(inanition) (of unknown origin) (persistent) (with chills) (with rigor)
      • pretibial
    • Fever(inanition) (of unknown origin) (persistent) (with chills) (with rigor)
      • seven day (leptospirosis) (autumnal) (Japanese)
    • Fort Bragg fever
    • Infection, infected, infective(opportunistic)
      • Leptospira interrogans
        • autumnalis
    • Infection, infected, infective(opportunistic)
      • Leptospira interrogans
        • canicola
    • Infection, infected, infective(opportunistic)
      • Leptospira interrogans
        • hebdomadis
    • Infection, infected, infective(opportunistic)
      • Leptospira interrogans
        • pomona
    • Infection, infected, infective(opportunistic)
      • Leptospira interrogans
        • specified type NEC
    • Leptospirosis
      • canicola
    • Leptospirosis
      • pomona
    • Nanukayami

Clinical ClassificationClinical

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

CCSR INF003
Bacterial infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Scrub Typhus

    an acute infectious disease caused by orientia tsutsugamushi. it is limited to eastern and southeastern asia, india, northern australia, and the adjacent islands. characteristics include the formation of a primary cutaneous lesion at the site of the bite of an infected mite, fever lasting about two weeks, and a maculopapular rash.

  • Orientia tsutsugamushi

    a gram-negative, rod-shaped to coccoid bacterium. it is the etiologic agent of scrub typhus in humans and is transmitted by mites from rodent reservoirs.

Patient EducationClinical

Bacterial Infections

Bacteria are tiny organisms (living things) that have only one cell. Under a microscope, they look like balls, rods, or spirals. They can be found almost everywhere on Earth. There are lots of bacteria in and on your body. In fact, your body has about 10 times more bacteria cells than human cells.

The full article covers:

  • What are bacteria?
  • How do bacterial infections spread?
  • What are the treatments for bacterial infections?
  • Can bacterial infections be prevented?

Read the full article at MedlinePlus

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

Convert A27.89 to ICD-9-CMHistory

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

ICD-9-CM
100.89 Leptospiral infect NEC
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 A27.89Overview

Is A27.89 (Other forms of leptospirosis) a billable code?

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

What is the ICD-9 equivalent of A27.89?

Under the General Equivalence Mappings, other forms of leptospirosis converts to ICD-9-CM 100.89 (leptospiral infect NEC). 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.