The nurse notes that a 1-day-old infant's immunoglobulin M (IgM) antibodies are elevated. Which is the least likely cause for this elevation?

Question

1. Placental leakage
2. Intrauterine exposure to syphilis
3. Intrauterine exposure to TORCH (toxoplasmosis, rubella, cytomegalovirus, herpesvirus hominis type 2 infection) syndrome
4. Maternal–fetal transfer of IgM while in utero

Answer 1

4
Explanation:
1. Elevated levels of IgM at birth may indicate placental leaks.
2. Elevations in IgM may be due to newborn exposure to an intrauterine infection such as syphilis.
3. Elevations in IgM at birth may be due to newborn exposure to an intrauterine infection such as TORCH syndrome.
4. Because IgM does not normally cross the placenta, most or all of it is produced by the fetus beginning at 10 to 15 weeks' gestation.