ICD-10-CM 2027
ICD-10 code for Reactivated serology for syphilis
From the official ICD-10-CM alphabetic index entry “Serology for syphilis › reactivated”. Page updated September 29, 2026.
About coding Reactivated serology for syphilis
The ICD-10-CM code for Reactivated serology for syphilis is A53.0 (Latent syphilis, unspecified as early or late).
Within A53, choose A53.0 (Latent syphilis, unspecified as early or late) only when documentation doesn't support a more specific option: syphilis, unspecified (A53.9).
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.
Common questions about Reactivated serology for syphilis ICD-10 codes
What is the ICD-10 code for Reactivated serology for syphilis?
- A53.0 — Latent syphilis, unspecified as early or late.
Is A53.0 billable?
- Yes. A53.0 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A53.0 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A53.0 as a principal diagnosis.
Is A53.0 a CC or MCC?
- No. A53.0 is neither a CC nor an MCC under MS-DRG v44.0.