ICD-10-CM 2027
ICD-10 code for lymphadenopathy
From the official ICD-10-CM alphabetic index entry “Lymphadenopathy (generalized)”. Page updated September 29, 2026.
About coding lymphadenopathy
The ICD-10-CM code for lymphadenopathy is R59.1 (Generalized enlarged lymph nodes). The official index lists 5 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on R59.1.
Within R59 (enlarged lymph nodes), R59.1 is specifically for generalized enlarged lymph nodes. Related codes cover localized enlarged lymph nodes (R59.0) and unspecified (R59.9).
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 814 (Reticuloendothelial and Immunity Disorders with MCC, relative weight 2.0729), DRG 815 (Reticuloendothelial and Immunity Disorders with CC, relative weight 1.0444) and DRG 816 (Reticuloendothelial and Immunity Disorders without CC/MCC, relative weight 0.7381), in MDC 16 (Diseases and Disorders of the Blood and Blood Forming Organs and Immunological Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific lymphadenopathy codes (official index)
- angioimmunoblastic, with dysproteinemia (AILD) C86.5 — Angioimmunoblastic T-cell lymphoma
- due to toxoplasmosis (acquired) B58.89 — Toxoplasmosis with other organ involvement
- congenital (acute) (subacute) (chronic) P37.1 — Congenital toxoplasmosis
- localized R59.0 — Localized enlarged lymph nodes
- syphilitic (early) (secondary) A51.49 — Other secondary syphilitic conditions
Common questions about lymphadenopathy ICD-10 codes
What is the ICD-10 code for lymphadenopathy?
- R59.1 — Generalized enlarged lymph nodes. More specific codes apply when the documentation supports them: C86.5, B58.89, P37.1, R59.0 and others below.
What is the ICD-10 code for localized lymphadenopathy?
- R59.0 — Localized enlarged lymph nodes.
What is the ICD-10 code for syphilitic lymphadenopathy?
- A51.49 — Other secondary syphilitic conditions.
Is R59.1 billable?
- Yes. R59.1 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can R59.1 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict R59.1 as a principal diagnosis.
Is R59.1 a CC or MCC?
- No. R59.1 is neither a CC nor an MCC under MS-DRG v44.0.