Question:

A day-old girl is being evaluated in the newborn nursery. The patient was born at 39 weeks gestation to a 38-year-old primigravida who immigrated to the United States during her third trimester. The patient had a strong cry and good tone at delivery but appears small for gestational age. Apgar scores were 8 and 9 at 1 and 5 minutes, respectively. Physical examination demonstrates white pupils bilaterally. A continuous harsh murmur is heard over the left infraclavicular area. The abdomen is nondistended, and there is no hepatosplenomegaly. Both ears fail the hearing screening. Which of the following maternal interventions would have most likely prevented this infant's condition?

Maternal administration of a killed vaccine during pregnancy

Maternal administration of a live attenuated vaccine before conception

Maternal perinatal antibiotic treatment

Maternal vitamin intake throughout pregnancy

Viral enzyme inhibitor drug intake during the third trimester

Welcome to USMLEPREPS!

Master your USMLE exams with our comprehensive question bank.

Subscribe to our Life Time Plan for unlimited access to Step 1, Step 2, and Step 3 preparation materials.

Don't miss this offer!

Hurry up!

: : Get The Offer

Unlimited Access Step ( one, two and three ).

Priority Access To New Features.

Free Lifetime Updates Facility.

Dedicated Support.

Explanation:

There are many explanatory sources, such as pictures, videos, and audio clips to explain these explanations and questions and explain the answers, but you must subscribe first so that you can enjoy all these advantages. We have many subscription plans at the lowest prices. Don't miss today's offer. Subscribe

Congenital rubella syndrome
Pathogenesis	Transplacental transmission
Classic features	Growth restriction Sensorineural hearing loss Congenital heart disease (eg, patent ductus arteriosus) Eye disease (eg, cataracts, glaucoma, retinopathy) CNS abnormalities (eg, developmental delay)
Diagnosis	Rubella IgM PCR or viral culture
Prevention	Maternal preconception immunization with live attenuated rubella vaccine

This neonate has the classic triad of findings for congenital rubella syndrome (CRS), including cataracts (white pupils), sensorineural hearing loss, and patent ductus arteriosus (continuous, harsh murmur). Growth restriction and CNS involvement may also occur. CRS is caused by transplacental transmission of the rubella virus from an infected mother. In pregnant women, rubella infection can cause nonspecific flu-like symptoms (eg, fever, malaise), arthralgias, and a rash with cephalocaudal progression. However, infection can also be asymptomatic, which likely occurred in this case.

Prevention of CRS is achieved by preventing maternal illness. Maternal rubella infection is rare in the United States because of universal childhood vaccination with the measles, mumps, and rubella (MMR) vaccine. However, lack of immunization programs in certain areas (eg, Southeast Asia, Africa) is associated with higher rates of CRS.

In contrast to killed vaccines that induce only humoral immunity, the rubella vaccine is a live attenuated vaccine and therefore induces both humoral and cell-mediated immunity (Choice A). Vaccination should be administered prior to conception because live attenuated vaccines carry the potential risk of viral transmission to the fetus if given during pregnancy.

(Choice C) Maternal perinatal antibiotic treatment is indicated for chorioamnionitis and group B Streptococcus colonization, which are risk factors for neonatal sepsis. Signs of sepsis in the immediate newborn period can include lethargy, temperature instability, and/or respiratory distress, not cataracts and hearing loss.

(Choice D) Prenatal folic acid helps prevent neural tube defects, in which the brain and/or spinal cord fail to develop properly. Affected infants may have a cutaneous abnormality (eg, hair tuft) in the lumbosacral area, lower extremity weakness, or hypotonia.

(Choice E) Antiviral therapy is indicated for pregnant women with HIV to decrease the risk of vertical transmission. In contrast to this patient, newborns with HIV are typically asymptomatic and develop failure to thrive and chronic diarrhea later in infancy.

Educational objective:
The classic triad of findings for congenital rubella syndrome includes cataracts, sensorineural hearing loss, and patent ductus arteriosus. Prevention consists of maternal preconception immunization with the live attenuated rubella vaccine.