Z16.35Resistance to multiple antimicrobial drugs

Z16.35 is the ICD-10-CM diagnosis code for resistance to multiple antimicrobial drugs. It belongs to category Z16 (resistance to antimicrobial drugs), block Z16 (resistance to antimicrobial drugs) and chapter 21 (factors influencing health status and contact with health services). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within Z16.3 (resistance to other antimicrobial drugs), Z16.35 is specifically for resistance to multiple antimicrobial drugs. Related codes cover unspecified antimicrobial drugs (Z16.30), antiparasitic drug(s) (Z16.31), antifungal drug(s) (Z16.32), antiviral drug(s) (Z16.33), antimycobacterial drug(s) (Z16.34) and other specified antimicrobial drug (Z16.39).

Don't report Z16.35 together with the conditions in its Excludes1 note: Resistance to multiple antibiotics only (Z16.24).

Code first: the infection.

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 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC, relative weight 2.1859), DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC, relative weight 1.0235) and DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC, relative weight 0.6787), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), 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 is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.

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 V09.81 (infection with microorganisms with resistance to multiple drugs).