Skip to main content
Compare/A55 vs B20

A55 vs B20

A55 (Chlamydial lymphogranuloma (venereum)) compared with B20 (Human immunodeficiency virus [HIV] disease), 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. A55 carries an Excludes2 note covering B20: “human immunodeficiency virus [HIV] disease (B20)”

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

Side by side

A55Chlamydial lymphogranuloma (venereum)B20Human immunodeficiency virus [HIV] disease
Billing statusBillableBillable
ClassificationA00-B99 — Certain Infectious and Parasitic Diseases (A00-B99)A00-B99 — Certain Infectious and Parasitic Diseases (A00-B99)
DefinitionChlamydial lymphogranuloma (venereum) is a billable ICD-10-CM diagnosis code (A55).Human immunodeficiency virus [HIV] disease is a billable ICD-10-CM diagnosis code (B20).
Includes
Climatic or tropical bubo
Durand-Nicolas-Favre disease
Esthiomene
Lymphogranuloma inguinale
acquired immune deficiency syndrome [AIDS]
AIDS-related complex [ARC]
HIV infection, symptomatic
Use additional code
code(s) to identify all manifestations of HIV infection
Code first
Human immunodeficiency virus [HIV] disease complicating pregnancy, childbirth and the puerperium, if applicable (O98.7-)

Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources