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ICD-10-CM 2027 diagnosis code

A36.85Diphtheritic cystitis

✓ Billable / specificCC — complication/comorbidity

A36.85 is a valid, billable ICD-10-CM code for diphtheritic cystitis. 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 A36.85

A36.85 is the ICD-10-CM diagnosis code for diphtheritic cystitis. It belongs to category A36 (diphtheria), block A30-A49 (other bacterial diseases) 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 A36.8 (other diphtheria), A36.85 is specifically for diphtheritic cystitis. Related codes cover diphtheritic cardiomyopathy (A36.81), diphtheritic radiculomyelitis (A36.82), diphtheritic polyneuritis (A36.83), diphtheritic tubulo-interstitial nephropathy (A36.84), diphtheritic conjunctivitis (A36.86) and other diphtheritic complications (A36.89).

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 689 (Kidney and Urinary Tract Infections with MCC, relative weight 1.1415) and DRG 690 (Kidney and Urinary Tract Infections without MCC, relative weight 0.801), in MDC 11 (Diseases and Disorders of the Kidney and Urinary Tract), 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 032.84 (diphtheritic cystitis).

Notes that apply from higher levels

Instructions written at a parent level also apply to A36.85.

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

Alphabetic index entries

1 entries

Terms in the official ICD-10-CM index that lead to A36.85.

Codes whose notes reference A36.85

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.

ICD-9-CM equivalent

Converter →
  • 032.84Diphtheritic cystitisexact

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 A36.85

Is A36.85 billable?

Yes. A36.85 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).

Can A36.85 be used as a principal diagnosis?

Yes. The Medicare Code Editor doesn't restrict A36.85 as a principal diagnosis.

Is A36.85 a CC or MCC?

A36.85 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.

What DRG does A36.85 group to?

A36.85 is used in the MS-DRG v44.0 logic for MS-DRG 689 (Kidney and Urinary Tract Infections with MCC) and MS-DRG 690 (Kidney and Urinary Tract Infections 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 A36.85?

The CMS General Equivalence Mappings map A36.85 to ICD-9-CM 032.84.