ICD-10 code for rat-bite fever

The ICD-10-CM code for rat-bite fever is A25.9 (Rat-bite fever, unspecified). The official index lists 2 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on A25.9.

Within A25, choose A25.9 (Rat-bite fever, unspecified) only when documentation doesn't support a more specific option: Spirillosis (A25.0) and Streptobacillosis (A25.1).

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 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.