ICD-10-CM 2027
ICD-10 code for varicella pneumonia
From the official ICD-10-CM alphabetic index entry “Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved) › varicella”. Page updated September 29, 2026.
About coding varicella pneumonia
The ICD-10-CM code for varicella pneumonia is B01.2 (Varicella pneumonia).
Within B01 (varicella [chickenpox]), B01.2 is specifically for varicella pneumonia. Related codes cover meningitis (B01.0), encephalitis, myelitis and encephalomyelitis (B01.1), with other complications (B01.8) and without complication (B01.9).
As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" 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 177 (Respiratory Infections and Inflammations with MCC, relative weight 1.6092), DRG 178 (Respiratory Infections and Inflammations with CC, relative weight 0.9744), DRG 179 (Respiratory Infections and Inflammations without CC/MCC, relative weight 0.7345), DRG 791 (Prematurity with Major Problems, relative weight 4.1075) and DRG 793 (Full Term Neonate with Major Problems, relative weight 4.2195), in MDC 04 (Diseases and Disorders of the Respiratory System) and MDC 15 (Newborns and Other Neonates with Conditions Originating in the Perinatal Period), 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 varicella pneumonia ICD-10 codes
What is the ICD-10 code for varicella pneumonia?
- B01.2 — Varicella pneumonia.
Is B01.2 billable?
- Yes. B01.2 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can B01.2 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict B01.2 as a principal diagnosis.
Is B01.2 a CC or MCC?
- B01.2 is an MCC (major complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.