A39.1Waterhouse-Friderichsen syndrome

A39.1 is the ICD-10-CM diagnosis code for Waterhouse-Friderichsen syndrome. It belongs to category A39 (meningococcal infection), 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 A39 (meningococcal infection), A39.1 is specifically for Waterhouse-Friderichsen syndrome. Related codes cover meningococcal meningitis (A39.0), acute meningococcemia (A39.2), chronic meningococcemia (A39.3), meningococcemia, unspecified (A39.4), meningococcal heart disease (A39.5), other meningococcal infections (A39.8) and unspecified (A39.9).

As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" 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 791 (Prematurity with Major Problems, relative weight 4.1075), DRG 793 (Full Term Neonate with Major Problems, relative weight 4.2195), DRG 870 (Septicemia or Severe Sepsis with MV >96 Hours, relative weight 6.9408), DRG 871 (Septicemia or Severe Sepsis without MV >96 Hours with MCC, relative weight 1.932) and DRG 872 (Septicemia or Severe Sepsis without MV >96 Hours without MCC, relative weight 1.0066), in MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period) and 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 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 036.3 (Waterhouse-Friderichsen syndrome, meningococcal).