ICD-10-CM 2027
ICD-10 code for synovium syphilis
From the official ICD-10-CM alphabetic index entry “Syphilis, syphilitic (acquired) › synovium”. Page updated September 29, 2026.
About coding synovium syphilis
The ICD-10-CM code for synovium syphilis is A52.78 (Syphilis of other musculoskeletal tissue).
Within A52.7, choose A52.78 (Syphilis of other musculoskeletal tissue) only when documentation doesn't support a more specific option: late syphilitic oculopathy (A52.71), syphilis of lung and bronchus (A52.72), symptomatic late syphilis of other respiratory organs (A52.73), syphilis of liver and other viscera (A52.74), syphilis of kidney and ureter (A52.75), other genitourinary symptomatic late syphilis (A52.76), syphilis of bone and joint (A52.77) and other symptomatic late syphilis (A52.79).
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 557 (Tendonitis, Myositis and Bursitis with MCC, relative weight 1.489) and DRG 558 (Tendonitis, Myositis and Bursitis without MCC, relative weight 0.8875), in MDC 08 (Diseases and Disorders of the Musculoskeletal System and Connective Tissue), 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 synovium syphilis ICD-10 codes
What is the ICD-10 code for synovium syphilis?
- A52.78 — Syphilis of other musculoskeletal tissue.
Is A52.78 billable?
- Yes. A52.78 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A52.78 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A52.78 as a principal diagnosis.
Is A52.78 a CC or MCC?
- A52.78 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.