Congenital defects — MCQs

Question 261: A male neonate is being examined by a pediatrician. His mother informs the doctor that she had a mild fever with rash, muscle pain, and swollen and tender lymph nodes during the second month of gestation. The boy was born at 39 weeks gestation via spontaneous vaginal delivery with no prenatal care. On physical examination, the neonate has normal vital signs. Retinal examination reveals the findings shown in the image. Which of the following congenital heart defects is most likely to be present in this neonate?

• A. Double outlet right ventricle
• B. Atrial septal defect
• C. Patent ductus arteriosus (Correct Answer)
• D. Ventricular septal defect
• E. Tetralogy of Fallot

Explanation: ***Patent ductus arteriosus*** - This neonate has **congenital rubella syndrome (CRS)** based on maternal symptoms during the first trimester (fever, rash, lymphadenopathy) and the characteristic **"salt and pepper" retinopathy** shown on retinal examination - **PDA is the most common cardiac defect** associated with CRS, occurring in approximately 50-85% of affected infants - Other cardiac manifestations of CRS include peripheral pulmonary artery stenosis, but PDA predominates - The classic triad of CRS includes cardiac defects, ocular abnormalities (cataracts, glaucoma, retinopathy), and sensorineural deafness *Double outlet right ventricle* - This is a **conotruncal anomaly** typically presenting with cyanosis in the neonatal period - Not associated with maternal rubella infection or congenital rubella syndrome - Would present with abnormal ventricular anatomy and significant hemodynamic compromise *Atrial septal defect* - While ASD is a common congenital heart defect, it is **not characteristically associated with CRS** - Much less frequently linked to maternal viral infections compared to PDA - Often asymptomatic in the neonatal period and detected later in childhood *Ventricular septal defect* - VSD is less commonly associated with **congenital rubella syndrome** compared to PDA - When present, typically manifests with a holosystolic murmur at the left lower sternal border - Can occur with maternal infections but is not the predominant cardiac finding in CRS *Tetralogy of Fallot* - Consists of four anatomic abnormalities: VSD, pulmonary stenosis, overriding aorta, and right ventricular hypertrophy - Presents with **cyanosis** ("tet spells") and is not specifically linked to maternal rubella infection - Not part of the congenital rubella syndrome spectrum