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ICD-10-CM 2027 diagnosis code

B85.4Mixed pediculosis and phthiriasis

✓ Billable / specific

B85.4 is a valid, billable ICD-10-CM code for mixed pediculosis and phthiriasis. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.

Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data

About B85.4

B85.4 is the ICD-10-CM diagnosis code for mixed pediculosis and phthiriasis. It belongs to category B85 (pediculosis and phthiriasis), block B85-B89 (pediculosis, acariasis and other infestations) and chapter 1 (certain infectious and parasitic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within B85 (pediculosis and phthiriasis), B85.4 is specifically for mixed pediculosis and phthiriasis. Related codes cover pediculosis due to Pediculus humanus capitis (B85.0), pediculosis due to Pediculus humanus corporis (B85.1), pediculosis, unspecified (B85.2) and phthiriasis (B85.3).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 606 (Minor Skin Disorders with MCC, relative weight 1.5728) and DRG 607 (Minor Skin Disorders without MCC, relative weight 0.8772), in MDC 09 (Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 132.3 (mixed pediculosis infestation).

Coding notes

Applicable toConditions and synonyms classified to this code
  • Infestation classifiable to more than one of the categories B85.0-B85.3

Notes that apply from higher levels

Instructions written at a parent level also apply to B85.4.

Broader instructions also apply from Chapter 1: Certain infectious and parasitic diseases.

Alphabetic index entries

3 entries

Terms in the official ICD-10-CM index that lead to B85.4.

MS-DRG v44.0 grouping

All DRGs →

Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.

MDC 09 · Diseases and Disorders of the Skin, Subcutaneous Tissue and Breast

ICD-9-CM equivalent

Converter →
  • 132.3Mixed pediculosis infestationexact

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • No changes since FY2016.

Common questions about B85.4

Is B85.4 billable?

Yes. B85.4 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can B85.4 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict B85.4 as a principal diagnosis.

Is B85.4 a CC or MCC?

No. B85.4 is neither a CC nor an MCC under MS-DRG v44.0.

What DRG does B85.4 group to?

B85.4 is used in the MS-DRG v44.0 logic for MS-DRG 606 (Minor Skin Disorders with MCC) and MS-DRG 607 (Minor Skin Disorders without MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.

What is the ICD-9 code for B85.4?

The CMS General Equivalence Mappings map B85.4 to ICD-9-CM 132.3.