2026 ICD-10-CM Diagnosis Code A28.1Cat-scratch disease

ICD-10-CM Codes›A00–B99›A20-A28›A28

ICD-10-CM A28.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A28.1 is a billable ICD-10-CM diagnosis code for cat-scratch disease. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 814 through 816. 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 1 closely related codes. Coders also document this condition as cat scratch disease. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections.

Code Identity

ICD-10-CM Code
A28.1
Billable Status
Yes — Valid for Submission
Code Describes
Cat-scratch disease
Short Description
Cat-scratch disease
Same as the full description in the CMS dataset.
Parent Code
A28
Other zoonotic bacterial diseases, not elsewhere classified

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA20-A28Certain zoonotic bacterial diseases
CategoryA28Other zoonotic bacterial diseases, not elsewhere classified
This CodeA28.1Cat-scratch disease

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cat scratch disease

Tabular List NotesGuidance

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

Inclusion Terms

  • Cat-scratch fever

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

Patient EducationClinical

Cat Scratch Disease

Cat scratch disease (CSD) is an illness caused by the bacterium Bartonella henselae. Almost half of all cats carry the infection at some point. The infection does not make cats sick. However, the scratch or bite of an infected cat can cause symptoms in people, including :

Read the full article at MedlinePlus

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

Convert A28.1 to ICD-9-CMHistory

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

ICD-9-CM
078.3 Cat-scratch disease
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 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About A28.1Overview

What is the ICD-10 code for cat-scratch disease?

The ICD-10-CM code for cat-scratch disease is A28.1 (sometimes written as A281). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is A28.1 (Other zoonotic bacterial diseases, not elsewhere classified) a billable code?

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

What MS-DRG does A28.1 group to?

When cat-scratch disease is the principal diagnosis on an inpatient stay, it groups to MS-DRG 814, 815, 816, with relative weights from 0.6320 to 2.1267 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A28.1 a CC or MCC?

CMS lists A28.1 as a CC (complication or comorbidity) for FY 2026. 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 1 closely related codes in its exclusion list.

What is the ICD-9 equivalent of A28.1?

Under the General Equivalence Mappings, cat-scratch disease converts to ICD-9-CM 078.3 (cat-scratch disease). The mapping is a direct match.