2026 ICD-10-CM Diagnosis Code I82.559Chronic embolism and thrombosis of unspecified peroneal vein

ICD-10-CM Codes›I00–I99›I80-I89›I82

ICD-10-CM I82.559
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I82.559 is a billable ICD-10-CM diagnosis code for chronic embolism and thrombosis of unspecified peroneal vein. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 299 through 301. The code is flagged as an unspecified code, since codes identifying laterality exist in the same family. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Chronic phlebitis; thrombophlebitis and thromboembolism.

Code Identity

ICD-10-CM Code
I82.559
Billable Status
Yes — Valid for Submission
Code Describes
Chronic embolism and thrombosis of unspecified peroneal vein
Short Description
Chronic embolism and thrombosis of unspecified peroneal vein
Same as the full description in the CMS dataset.
Parent Code
I82.55
Chronic embolism and thrombosis of peroneal vein

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI80-I89Diseases of veins, lymphatic vessels and lymph nodes, not elsewhere classified
CategoryI82Other venous embolism and thrombosis
This CodeI82.559Chronic embolism and thrombosis of unspecified peroneal vein

Code EditsBilling

Medicare Code Editor checks that affect claim validity for I82.559.

Unspecified codes
Unspecified codes exist in the ICD-10-CM classification for circumstances when documentation in the medical record does not provide the level of detail needed to support reporting a more specific code. However, in the inpatient setting, there should generally be very limited and rare circumstances for which the laterality (right, left, bilateral) of a condition is unable to be documented and reported. The following pages contain the list of unspecified ICD-10-CM diagnosis codes for which there is a more specific code to identify laterality (right, left, bilateral) within that code family.

Clinical ClassificationClinical

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

CCSR CIR034
Chronic phlebitis; thrombophlebitis and thromboembolism
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Deep Vein Thrombosis

Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep in the body. Most deep vein clots occur in the lower leg or thigh. If the vein swells, the condition is called thrombophlebitis. A deep vein thrombosis can break loose and cause a serious problem in the lung, called a pulmonary embolism.

Read the full article at MedlinePlus

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

Code History & ChangesHistory

Replacement I82.559 replaces the following previously assigned code(s):

  • I82.599 - Chronic embolism and thombos of deep vein of unsp low extrm
FY 2020AddedAdded to the ICD-10-CM code setEffective October 1, 2019.
FY 2021–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About I82.559Overview

Is I82.559 (Chronic embolism and thrombosis of peroneal vein) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report chronic embolism and thrombosis of unspecified peroneal vein on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does I82.559 group to?

When chronic embolism and thrombosis of unspecified peroneal vein is the principal diagnosis on an inpatient stay, it groups to MS-DRG 299, 300, 301, with relative weights from 0.7197 to 1.6327 depending on complications. Higher weights mean higher Medicare reimbursement.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.