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Compare/A53 vs A66

A53 vs A66

A53 (Other and unspecified syphilis) compared with A66 (Yaws), from the official CMS tabular data. Both may be reported when both conditions are documented (Excludes2).

Can these codes be reported together?

Yes, when both are documented. A66 carries an Excludes2 note covering A53: “syphilis (A50-A53)”

Excludes2 marks distinct conditions — both may be reported when both are documented.

Side by side

A53Other and unspecified syphilisA66Yaws
Billing statusNon-billable header

Report instead: A53.0, A53.9

Non-billable header

Report instead: A66.0, A66.1, A66.2, A66.3, A66.4

ClassificationA00-B99 — Certain Infectious and Parasitic Diseases (A00-B99)A00-B99 — Certain Infectious and Parasitic Diseases (A00-B99)
DefinitionOther and unspecified syphilis is a non-billable ICD-10-CM category code (A53).Yaws is a non-billable ICD-10-CM category code (A66).
Includes—
bouba
frambesia (tropica)
pian
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Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources