Related Subjects:
| Systemic Lupus Erythematosus (SLE)
| Drug-induced Lupus Erythematosus
| Discoid Lupus Erythematosus (DLE)
| Neonatal Lupus Erythematosus
About Neonatal Lupus Erythematosus
Neonatal Lupus Erythematosus (NLE) is a rare autoimmune condition affecting infants born to mothers who have autoantibodies against Ro/SSA and La/SSB antigens. While some mothers may have a known diagnosis of Systemic Lupus Erythematosus (SLE) or other autoimmune diseases, others may be asymptomatic carriers of these antibodies.
Aetiology
- Maternal IgG autoantibodies, specifically Anti-Ro (SSA) and Anti-La (SSB), cross the placenta during pregnancy.
- These antibodies can bind to fetal tissues, leading to inflammation and damage.
Clinical Effects on the Fetus and Neonate
- Cardiac Manifestations:
- Congenital heart block (first, second, or third degree), which may lead to bradycardia and, in severe cases, congestive heart failure.
- Cardiomyopathy and endocardial fibroelastosis in some cases.
- Dermatological Manifestations:
- Circular or elliptical erythematous rash, often with central clearing, typically appearing on the face, scalp, and periorbital areas ("raccoon eyes").
- Rash may be exacerbated by exposure to ultraviolet light.
- Hematological Manifestations:
- Haemolytic anemia.
- Thrombocytopenia (low platelet count).
- Neutropenia (low neutrophil count).
- Hepatic Manifestations:
- Elevated liver enzymes indicating hepatocellular damage.
- Hepatomegaly (enlarged liver).
Investigations
- Maternal Testing:
- Serological testing for Anti-Ro (SSA) and Anti-La (SSB) antibodies.
- Assessment for underlying autoimmune diseases like SLE or Sjögren's syndrome.
- Prenatal Monitoring:
- Serial fetal echocardiography starting from 16 weeks' gestation to detect early signs of heart block.
- Monitoring fetal heart rate for bradycardia.
- Neonatal Testing:
- Electrocardiogram (ECG) and echocardiogram to evaluate cardiac involvement.
- Complete blood count (CBC) to assess anemia, thrombocytopenia, and neutropenia.
- Liver function tests to detect hepatic involvement.
- Skin biopsy (rarely needed) to confirm diagnosis of skin lesions.
Management
- Prenatal Management:
- Close monitoring of at-risk pregnancies with serial ultrasounds and fetal echocardiography.
- Consideration of maternal corticosteroid therapy to reduce antibody levels (use is controversial and should be guided by a specialist).
- Potential use of hydroxychloroquine in pregnant women with positive antibodies to reduce risk.
- Postnatal Management:
- Cardiac Management:
- Insertion of a pacemaker in cases of complete (third-degree) heart block.
- Treatment of heart failure with medications as needed.
- Regular cardiology follow-up for ongoing assessment.
- Dermatological Management:
- Avoidance of sun exposure; use of protective clothing and sunscreen.
- Topical corticosteroids may be prescribed for skin lesions.
- Most skin manifestations resolve spontaneously as maternal antibodies wane.
- Hematological Management:
- Monitoring blood counts regularly.
- Blood transfusions may be necessary for severe anemia.
- Management of infections due to neutropenia.
- Hepatic Management:
- Supportive care as liver function typically normalizes over time.
- Parental Support and Education:
- Provide information about the condition, prognosis, and potential complications.
- Genetic counseling may be offered for future pregnancies.
Prognosis
- Non-cardiac manifestations (skin, liver, hematological) usually resolve by 6 to 8 months of age as maternal antibodies are cleared.
- Congenital heart block is often permanent and may require lifelong pacing and cardiology care.
- With appropriate management, many infants can lead healthy lives.
References