Neonatal lupus is an uncommon
autoimmune disease manifested primarily by cutaneous lupus lesions and/or
congenital heart block. Maternal
autoantibodies of the Ro/La family are present in virtually every case, although only approximately 1% of women who have these
autoantibodies will have a baby with
neonatal lupus. The cutaneous lesions of
neonatal lupus may be present at birth, but more often develop within the first few weeks of life. Lesions are most common on the face and scalp, often in a distinctive periorbital distribution. Lesions tend to resolve in a few weeks or months without
scarring. The most common cardiac manifestation of
neonatal lupus is complete
heart block.
Heart block typically begins in utero during the second or third trimester. In some cases,
heart block begins as first- or second-degree block and then progresses to third-degree block. Complete
heart block, once established, appears to be irreversible. In some cases,
cardiomyopathy occurs together with complete
heart block. Most cases have been noted at birth, but delayed
dilated cardiomyopathy has been reported. There have been a few cases of
endocardial fibroelastosis occurring in the absence of
congenital heart block.
Hepatobiliary disease occurs in about 10% of cases. Three types of
hepatobiliary disease have been observed:
liver failure occurring at birth or in utero, transient conjugated
hyperbilirubinemia occurring in infants, or transient
transaminase elevations occurring in infants.
Hematologic disease, consisting of
thrombocytopenia,
neutropenia, or
anemia, occurs in about 10% of cases. It is common for children with
neonatal lupus not to have the full expression of disease, but rather to have only one or two organ systems involved. The diagnosis rests largely on the finding of compatible clinical manifestations plus maternal
autoantibodies to Ro and/or La, or, in a few cases, to U1 ribonuclear
protein. Although the pathogenesis has not been conclusively established, accumulating evidence, including evidence from animal models, implicates
autoantibodies in the pathogenesis of the disease. Therapeutic interventions include attempts at prevention, early intervention, and treatment of well established disease, mainly through the use of systemic
corticosteroids. Optimal
therapy has yet to be determined. The long-term prognosis for children who have had
neonatal lupus is still under investigation, but some children who had
neonatal lupus have developed other
autoimmune diseases later in childhood. About half of the mothers are asymptomatic at the time of presentation of the child, but some of these women eventually develop symptoms of
autoimmune disease.