2027 ICD-10-CM Diagnosis Code B00.82Herpes simplex myelitis

ICD-10-CM Codes›A00–B99›B00-B09›B00

ICD-10-CM B00.82
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

B00.82 is a billable ICD-10-CM diagnosis code for herpes simplex myelitis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 23 through 24, 97 through 99. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 31 closely related codes. Coders also document this condition as herpes simplex type 1 infection. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Viral infection.

For Medicare Advantage risk adjustment, B00.82 maps to CMS-HCC Category 182 (Spinal Cord Disorders/Injuries) under the V28 model, adding a risk factor of about 0.478 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
B00.82
Billable Status
Yes — Valid for Submission
Code Describes
Herpes simplex myelitis
Short Description
Herpes simplex myelitis
Same as the full description in the CMS dataset.
Parent Code
Other forms of herpesviral infections

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB00-B09Viral infections characterized by skin and mucous membrane lesions
CategoryB00Herpesviral [herpes simplex] infections
This CodeB00.82Herpes simplex myelitis

Medicare Risk Adjustment (HCC)Billing

B00.82 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 182— Spinal Cord Disorders/Injuries
Payment HCC · PY 2027 one of 251 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.478
community, non-dual, aged · ranges 0.270–0.478 across segments
Hierarchy
Superseded by HCC 180, HCC 181, HCC 191, and HCC 192
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 72
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 72 · ESRD (V21): HCC 72 · ESRD (V24): HCC 72
ESRD V21 weights: 0.102 dialysis, 0.256–0.456 functioning graft · ESRD V24 weights: 0.099 dialysis, 0.222–0.523 functioning graft
Part D (RxHCC)
RxHCC 155 — Spinal Cord Disorders
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Herpes simplex type 1 infection
  • Herpes simplex type 2 infection
  • Myelitis caused by Herpes simplex type 1
  • Myelitis caused by Herpes simplex type 2
  • Myelitis caused by herpes virus
  • Myelitis caused by human herpes simplex virus

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to B00.82: its own notes plus those printed at B00 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

Excludes1

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

From B00 Herpesviral [herpes simplex] infections applies to 15 codes
  • congenital herpesviral infections (P35.2)

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 B00 Herpesviral [herpes simplex] infections applies to 15 codes
  • anogenital herpesviral infection (A60.-)
  • gammaherpesviral mononucleosis (B27.0-)
  • herpangina (B08.5)
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 B00.82, its category, or a range that includes it.

Excludes2 3

These codes carry an Excludes2 note naming B00.82: its condition is not part of those codes, and both may be reported when the patient has both.

  • B10 Other human herpesviruses
    herpes simplex (B00.-) names B00.-, which includes this code
  • B10 Other human herpesviruses
    human herpesvirus NOS (B00.-) names B00.-, which includes this code
  • B10 Other human herpesviruses
    human herpesvirus 1 and 2 (B00.-) names B00.-, which includes this code

Code Also 1

These codes say B00.82 may also be needed to fully describe the condition. The note gives no sequencing direction.

  • D81.82 Activated Phosphoinositide 3-kinase Delta Syndrome [APDS]
    herpes virus infections (B00.-) names B00.-, which includes this code

Index to Diseases and InjuriesGuidance

Clinical ClassificationClinical

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

CCSR INF008
Viral infection
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Herpes Simplex

Herpes is an infection that is caused by a herpes simplex virus (HSV). Oral herpes causes cold sores around the mouth or face. Genital herpes affects the genitals, buttocks or anal area. Genital herpes is a sexually transmitted infection (STI). It affects the genitals, buttocks or anal area.

Read the full article at MedlinePlus

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

Convert B00.82 to ICD-9-CMHistory

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

ICD-9-CM
054.74 Herpes simplex myelitis
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 B00.82Overview

What is the ICD-10 code for herpes simplex myelitis?

The ICD-10-CM code for herpes simplex myelitis is B00.82 (sometimes written as B0082). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is B00.82 (Other forms of herpesviral infections) a billable code?

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

What MS-DRG does B00.82 group to?

When herpes simplex myelitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 24, 98, 99, 23, 97, with relative weights from 1.5249 to 5.7422 depending on complications. Higher weights mean higher Medicare reimbursement.

Is B00.82 a CC or MCC?

CMS lists B00.82 as an MCC (major complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 31 closely related codes in its exclusion list.

Can B00.82 be reported with P35.2?

Not as a rule. The Excludes1 note at B00, which applies to B00.82, lists "congenital herpesviral infections (P35.2)". 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 HCC is B00.82?

B00.82 (herpes simplex myelitis) maps to CMS-HCC Category 182 (Spinal Cord Disorders/Injuries), commonly written as HCC 182, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 72 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 155.

Does B00.82 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, B00.82 adds a risk adjustment factor of about 0.478 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.270 to 0.478 depending on the payment segment). A more severe related category (HCC 180, HCC 181, HCC 191, and HCC 192) supersedes it when both are reported. See the full factor table on the HCC 182 category page.