A 31-year-old woman presents for obstetrical care for the first time and is found to be at 28 weeks’ gestation. She has no current complaints but reports a history of photosensitive malar rash, polyarthritis, cold fingers, and depression. She takes hydroxychloroquine and low-dose prednisone. Physical examination is unremarkable except for a gravid uterus, painless aphthous ulcer in the mouth, and mild Raynaud phenomenon in the distal fingers bilaterally. Fetal auscultation reveals bradycardia. Laboratory evaluation of the patient reveals a mild microcytic anemia, positive antibody titers for antinuclear, anti-dsDNA, anti-Ro/SSA, and anti-La/SSB antibodies.
Which of the following interventions is most likely to be required for the infant after birth?
E) Placement of a cardiac pacemaker
This patient has systemic lupus erythematosus (SLE). SLE can present in many ways, though classic findings include a photosensitive malar rash, Raynaud phenomenon, and polyarthritis, and aphthous ulcers. Labs may include cytopenias (such as anemia), and tests for specific antibodies such as antinuclear antibody, anti-dsDNA, and anti-Sm are often positive. Patients with SLE can also have antiphospholipid antibody and the antibodies anti-Ro/SSA and anti-La/SSB, which are typically associated with Sjögren syndrome. Pregnant women who are anti-Ro/SSA or anti-La/SSB positive are at risk for delivering infants with neonatal lupus, an autoimmune disease resulting from passive transfer of autoantibodies from the mother to the fetus, resulting in fetal and neonatal disease. The major manifestations are cardiac and cutaneous findings, with the most serious complication being complete heart block. Patients with neonatal lupus may develop first-, second-, or third-degree heart block, most commonly occurring between 18 to 25 weeks of gestation. Complete heart block results in fetal bradycardia that can be detected by routine fetal auscultation, though frequent fetal echocardiographic surveillance is advised for individuals who test positive for Ro/SSA and La/SSB autoantibodies. Complete heart block is treated with a cardiac pacemaker.
Answer choice A: Administration of intravenous indomethacin, is incorrect. Indomethacin is used to close a patent ductus arteriosus. SLE is not known to significantly increase the risk of PDA development in offspring.
Answer choice B: Administration of surfactant, is incorrect. Surfactant is used in neonatal respiratory distress syndrome. SLE is not known to significantly increase the risk of neonatal respiratory distress syndrome development in offspring.
Answer choice C: Evaluation for renal transplantation, is incorrect. While SLE often affects the kidneys, neonatal lupus typically does not include congenital renal involvement.
Answer choice D: Initiation of lifelong anticoagulation, is incorrect. Antiphospholipid syndrome in the setting of SLE is associated with an increased risk of arterial and venous thromboembolic events. In the absence of a thrombotic event for antiphospholipid-defining pregnancy morbidity (such as recurrent pregnancy loss), anticoagulation usually is not indicated. It would not be routinely indicated for an infant born to a mother with SLE.
Key Learning Point
Pregnant women with systemic lupus erythematosus who are positive for the anti-Ro/SSA or anti-La/SSB antibodies are at heightened risk of delivering an infant with neonatal lupus. The most concerning feature of neonatal lupus is congenital heart block. High-grade heart block, which presents with fetal bradycardia, typically requires cardiac pacemaker implantation.
