P35.1 Congenital cytomegalovirus infection

Name of the Condition

• Congenital cytomegalovirus infection
• ICD-10-CM Code: P35.1

Summary

This condition refers to cytomegalovirus (CMV) infection acquired by the fetus or newborn during pregnancy or delivery. It is a common congenital viral infection that can affect multiple organ systems and may present with a range of clinical manifestations in the newborn. The infection can be asymptomatic or cause severe complications, depending on the timing and severity of transmission.

Causes

Congenital cytomegalovirus infection is caused by vertical transmission of the cytomegalovirus from an infected mother to the fetus. Transmission can occur transplacentally during pregnancy or perinatally during delivery. The virus is transmitted through close contact with bodily fluids, such as saliva, urine, or breast milk, and can infect the fetus or newborn even if the mother is asymptomatic.

Risk Factors

• Maternal primary CMV infection during pregnancy (especially in the first trimester)
• Maternal reactivation of latent CMV infection
• Maternal CMV seropositivity with high viral load
• Lack of maternal immunity or prior exposure to CMV
• Prolonged rupture of membranes during labor
• Invasive fetal procedures (e.g., amniocentesis) during pregnancy

Symptoms

Symptoms vary and may include jaundice, hepatosplenomegaly, microcephaly, petechiae, chorioretinitis, hearing loss, or developmental delays. Some infants may be asymptomatic at birth but develop late-onset complications, such as sensorineural hearing loss or cognitive impairment. Severe cases can present with intrauterine growth restriction or stillbirth.

Diagnosis

Diagnosis involves maternal history, newborn physical examination, and laboratory testing. Prenatal diagnosis may include amniocentesis with PCR for CMV DNA. Postnatal testing includes viral cultures, PCR, or serology from urine, saliva, or blood samples. Imaging (e.g., ultrasound, MRI) may assess organ involvement, such as brain calcifications or hepatosplenomegaly.

Treatment Options

Treatment depends on symptom severity and organ involvement. Antiviral therapy (e.g., ganciclovir, valganciclovir) may be used for severe cases, particularly with central nervous system involvement. Supportive care includes management of jaundice, hearing loss, or other complications. Long-term monitoring for developmental delays or hearing loss is recommended.

Prognosis and Follow-Up

Prognosis varies based on symptom severity and organ involvement. Asymptomatic infants generally have a good prognosis, while those with severe symptoms (e.g., microcephaly, hearing loss) may have long-term complications. Follow-up includes regular hearing assessments, developmental evaluations, and monitoring for late-onset sequelae. Early intervention services may improve outcomes.

Complications

Complications can include sensorineural hearing loss, vision impairment (e.g., chorioretinitis), cognitive or developmental delays, seizures, or liver dysfunction. Some infants may experience chronic lung disease or growth failure. Late-onset complications, such as behavioral issues or learning disabilities, may emerge in childhood.

Lifestyle & Prevention

Prevention focuses on reducing maternal exposure to CMV, such as avoiding contact with young children’s bodily fluids (e.g., saliva, urine) and practicing good hand hygiene. Pregnant individuals with young children or in childcare settings should take precautions. No vaccine is currently available for CMV prevention.

When to Seek Professional Help

Seek medical attention if a newborn shows signs of infection (e.g., jaundice, poor feeding, lethargy) or if maternal exposure to CMV is suspected. Early evaluation is critical for infants with suspected congenital CMV to assess organ involvement and initiate treatment if needed. Regular follow-up is recommended for monitoring developmental milestones.

Tips for Medical Coders

Use code P35.1 for congenital cytomegalovirus infection. Document the timing of infection (prenatal vs. perinatal) and any associated complications (e.g., hearing loss, microcephaly) to support coding accuracy. Ensure differentiation from other congenital viral infections (e.g., rubella, herpes) and confirm CMV-specific testing or clinical findings.