2026 ICD-10-CM Diagnosis Code P35.1Congenital cytomegalovirus infection

ICD-10-CM Codes›P00–P96›P35-P39›P35

ICD-10-CM P35.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

P35.1 is a billable ICD-10-CM diagnosis code for congenital cytomegalovirus infection. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 791, 793. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 31 closely related codes. Coders also document this condition as chronic congenital cytomegalic inclusion disease. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Perinatal infections and Viral infection.

Code Identity

ICD-10-CM Code
P35.1
Billable Status
Yes — Valid for Submission
Code Describes
Congenital cytomegalovirus infection
Short Description
Congenital cytomegalovirus infection
Same as the full description in the CMS dataset.
Parent Code
P35
Congenital viral diseases

Code Classification

ChapterP00–P96Certain conditions originating in the perinatal period
SectionP35-P39Infections specific to the perinatal period
CategoryP35Congenital viral diseases
This CodeP35.1Congenital cytomegalovirus infection

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Chronic congenital cytomegalic inclusion disease
  • Congenital cytomegalovirus infection
  • Congenital infection caused by Herpes virus

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR PNL009
Perinatal infections
Default principal diagnosis: inpatient Yes · outpatient Yes
CCSR INF008
Viral infection
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Cytomegalovirus Infections

Cytomegalovirus (CMV) is a virus found around the world. It is related to the viruses that cause chickenpox and infectious mononucleosis (mono). Between 50% and 80% of adults in the United States have had a CMV infection by age 40. Once CMV is in a person's body, it stays there for life.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert P35.1 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
771.1 Cong cytomegalovirus inf
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About P35.1Overview

What is the ICD-10 code for congenital cytomegalovirus infection?

The ICD-10-CM code for congenital cytomegalovirus infection is P35.1 (sometimes written as P351). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is P35.1 (Congenital viral diseases) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report congenital cytomegalovirus infection on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does P35.1 group to?

When congenital cytomegalovirus infection is the principal diagnosis on an inpatient stay, it groups to MS-DRG 791, 793, with relative weights from 4.0590 to 4.1696 depending on complications. Higher weights mean higher Medicare reimbursement.

Is P35.1 a CC or MCC?

CMS lists P35.1 as an MCC (major complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 31 closely related codes in its exclusion list.

What is the ICD-9 equivalent of P35.1?

Under the General Equivalence Mappings, congenital cytomegalovirus infection converts to ICD-9-CM 771.1 (cong cytomegalovirus inf). The mapping is a direct match.