2026 ICD-10-CM Diagnosis Code A18.85Tuberculosis of spleen

ICD-10-CM Codes›A00–B99›A15-A19›A18

ICD-10-CM A18.85
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

A18.85 is a billable ICD-10-CM diagnosis code for tuberculosis of spleen. 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, 974 through 976. 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 15 closely related codes. Coders also document this condition as infection of spleen. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified hematologic conditions and Tuberculosis.

Code Identity

ICD-10-CM Code
A18.85
Billable Status
Yes — Valid for Submission
Code Describes
Tuberculosis of spleen
Short Description
Tuberculosis of spleen
Same as the full description in the CMS dataset.
Parent Code
A18.8
Tuberculosis of other specified organs

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionA15-A19Tuberculosis
CategoryA18Tuberculosis of other organs
This CodeA18.85Tuberculosis of spleen

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Infection of spleen
  • Tuberculosis of spleen

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 BLD010
Other specified and unspecified hematologic conditions
Default principal diagnosis: inpatient No · outpatient No
CCSR INF001
Tuberculosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Spleen Diseases

Your spleen is an organ above your stomach and under your ribs on your left side. It is about as big as your fist. The spleen is part of your lymphatic system, which fights infection and keeps your body fluids in balance. It contains white blood cells that fight germs.

Read the full article at MedlinePlus

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

Convert A18.85 to ICD-9-CMHistory

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

ICD-9-CM
017.70 TB of spleen-unspec
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 A18.85Overview

What is the ICD-10 code for tuberculosis of spleen?

The ICD-10-CM code for tuberculosis of spleen is A18.85 (sometimes written as A1885). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is A18.85 (Tuberculosis of other specified organs) a billable code?

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

What MS-DRG does A18.85 group to?

When tuberculosis of spleen is the principal diagnosis on an inpatient stay, it groups to MS-DRG 814, 815, 816, 974, 975, 976, with relative weights from 0.6320 to 2.8860 depending on complications. Higher weights mean higher Medicare reimbursement.

Is A18.85 a CC or MCC?

CMS lists A18.85 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 15 closely related codes in its exclusion list.

What is the ICD-9 equivalent of A18.85?

Under the General Equivalence Mappings, tuberculosis of spleen converts to ICD-9-CM 017.70 (TB of spleen-unspec). The mapping is approximate, so confirm the match fits the documentation.