2027 ICD-10-CM Diagnosis Code B02.21Postherpetic geniculate ganglionitis
ICD-10-CM Codes›A00–B99›B00-B09›B02
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Not Chronic
B02.21 is a billable ICD-10-CM diagnosis code for postherpetic geniculate ganglionitis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 73 through 74, 791, 793, 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 34 closely related codes. Coders also document this condition as acute geniculate ganglionitis caused by Human herpesvirus 3. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nerve and nerve root disorders and Viral infection.
B02.21 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 168 for payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
B02.21 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.
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.
- Acute geniculate ganglionitis caused by Human herpesvirus 3
- Facial neuralgia
- Geniculate ganglionitis
- Herpes zoster auricularis
- Herpes zoster dermatitis
- Nervus intermedius neuralgia
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to B02.21: its own notes plus those printed at B02 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.
- shingles
- zona
- diseases generally recognized as communicable or transmissible
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.
- 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.
- 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 B02.21, its category, or a range that includes it.
Excludes1 2
These codes carry an Excludes1 note naming B02.21: they are not reported together with it, unless the two conditions are unrelated.
Excludes2 4
These codes carry an Excludes2 note naming B02.21: its condition is not part of those codes, and both may be reported when the patient has both.
- B10 Other human herpesvirusesherpes zoster (B02.-) names B02.-, which includes this code
- B10 Other human herpesviruseshuman herpesvirus 3 (B01.-, B02.-) names B02.-, which includes this code
- B10 Other human herpesviruseszoster (B02.-) names B02.-, which includes this code
- Block L00-L08 Infections of the skin and subcutaneous tissuezoster (B02.-) names B02.-, which includes this code
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Disease, diseased See Also: Syndrome;
postherpetic, postzoster B02.21
herpes zoster B02.21
postherpetic geniculate B02.21
Herpes, herpesvirus, herpetic B00.9
geniculate ganglionitis B02.21
zoster See Also: condition; B02.9
auricularis B02.21
geniculate ganglionitis B02.21
oticus B02.21
Ramsay-Hunt disease or syndrome See Also: Hunt's, disease; B02.21
Syndrome See Also: Disease;
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Shingles
Shingles (herpes zoster) is an infection that causes a painful rash. It is caused by the varicella-zoster virus (VZV). This is the same virus that causes chickenpox. After you have chickenpox, the virus stays in your body. It may not cause problems for many years. But as you get older, the virus may become active again and cause shingles.
The full article covers:
- What is shingles?
- Is shingles contagious?
- Who is at risk for shingles?
- What are the symptoms of shingles?
- What other problems can shingles cause?
- How is shingles diagnosed?
- What are the treatments for shingles?
- Can shingles be prevented?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert B02.21 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About B02.21Overview
What is the ICD-10 code for postherpetic geniculate ganglionitis?
The ICD-10-CM code for postherpetic geniculate ganglionitis is B02.21 (sometimes written as B0221). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is B02.21 (Zoster with other nervous system involvement) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report postherpetic geniculate ganglionitis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does B02.21 group to?
When postherpetic geniculate ganglionitis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 974, 74, 976, 73, 975, with relative weights from 0.7879 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.
Is B02.21 a CC or MCC?
CMS lists B02.21 as a CC (complication or comorbidity) for FY 2027. 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 34 closely related codes in its exclusion list.
What is the ICD-9 equivalent of B02.21?
Under the General Equivalence Mappings, postherpetic geniculate ganglionitis converts to ICD-9-CM 053.11 (geniculate herpes zoster). The mapping is a direct match.
Does B02.21 risk-adjust for Medicare Advantage payment?
Not for Medicare Advantage: B02.21 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 168 (Trigeminal and Postherpetic Neuralgia).
