A51.49Other secondary syphilitic conditions

A51.49 is the ICD-10-CM diagnosis code for other secondary syphilitic conditions. It belongs to category A51 (early syphilis), block A50-A64 (infections with a predominantly sexual mode of transmission) 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 A51.4, choose A51.49 (Other secondary syphilitic conditions) only when documentation doesn't support a more specific option: secondary syphilitic meningitis (A51.41), secondary syphilitic female pelvic disease (A51.42), secondary syphilitic oculopathy (A51.43), secondary syphilitic nephritis (A51.44), secondary syphilitic hepatitis (A51.45) and secondary syphilitic osteopathy (A51.46).

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.

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 091.4 (Adenopathy due to secondary syphilis), 091.69 (secondary syphilis of other viscera), 091.7 (secondary syphilis, relapse) and 1 more.