A newborn is detected to have sensorineural deafness, congenital cataracts, and patent ductus arteriosus. Maternal history reveals a febrile rash illness in the first trimester. Which maternal serological result most likely explains this constellation?

• A Parvovirus B19 IgG positive in maternal serum
• B CMV IgG avidity test showing high avidity, indicating past maternal infection
• C Toxoplasma gondii IgG positive, IgM negative in maternal serum
• D Rubella IgM positive in maternal serum collected during the first trimester ✓

Explanation

The triad of deafness, cataracts, and patent ductus arteriosus is classic congenital rubella syndrome (Greg triad). Maternal rubella infection in the first trimester, confirmed by rubella-specific IgM, causes congenital defects due to viral cytopathic effect on developing fetal organs and inhibition of mitosis. CMV causes deafness but not cataracts or PDA. Toxoplasma causes chorioretinitis and hydrocephalus. Parvovirus B19 causes hydrops fetalis and aplastic crisis, not this triad.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.