Objective To evaluate autoimmune disease progression in asymptomatic and pauci-symptomatic mothers of children with neonatal lupus (NL).
Methods: Clinical information on mothers enrolled in the Research Registry (RRNL) was obtained from medical records. Genotyping was performed for -308A/G TNFα, 869T/C TGFβ, and -889C/T IL1α.
Results: Of the 321-mothers enrolled, 229 had at least six months of follow-up. Twenty-six of the fifty-one mothers who were asymptomatic at the NL-child's birth progressed: 12 developed pauci-undifferentiated autoimmune syndrome (UAS), two poly-UAS, seven SS, four SLE and one SLE/SS. The median time to develop any symptom was 3.15 years. Sixteen of the 37 mothers classified as pauci-UAS at the NL-child's birth progressed: five developed poly-UAS, six SS, four SLE, and one SLE/SS. Of the pauci-UAS mothers enrolled within one year, the median time to progression was 6.7 years. Four mothers developed lupus nephritis (two asymptomatic, two pauci-UAS). The probability of an asymptomatic mother developing SLE by 10 years was 18.6%, and developing probable/definite SS was 27.9%. NL-manifestations did not predict disease progression in an asymptomatic mother. Mothers with anti-SSA/Ro and anti-SSB/La were nearly twice as likely to develop an autoimmune disease as mothers with anti-SSA/Ro only. Only TGFβT/T was significantly higher in SLE-mothers compared to asymptomatic-mothers (p=0.03).
Conclusion: Continued follow-up of asymptomatic NL-mothers is warranted since nearly half progress, albeit few develop SLE. While the anti-SSB/La antibodies may be a risk factor for progression, further work is needed to determine reliable biomarkers in otherwise healthy women with anti-SSA/Ro antibodies identified solely because of an NL-child.