Preventing congenital neonatal heart block in offspring of mothers with anti-SSA/Ro and SSB/La antibodies: a review of published literature and registered clinical trials.

Offspring of women with anti-SSA/Ro-SSB/La antibodies are believed to be at risk for congenital heart block (CHB). Whether this risk can be reduced, and what constitutes standard of care treatment is, however, unclear. The objective of this review therefore was to determine whether currently proposed standard of care treatments to avoid CHB in offspring of mothers at risk are evidence-based. To do so, we conducted a review of the literature under appropriate keywords and phrases in Medline/PubMed and Google Scholar for the years 2000-2013. Reference lists were further reviewed, and relevant manuscripts were pulled. We also reviewed www.clinicaltrials.gov for registered studies. In the absence of randomized prospective clinical trials, a meta-analysis was not feasible. We, therefore, reviewed lower evidence level studies individually. Risk of CHB actually appears more closely associated with general autoimmunity than, specifically, with SSA/Ro-SSB/La antibodies. This and other observations raise questions whether CHB is caused by passively transferred maternal autoimmunity, as is currently widely believed. Observational studies suggest the possible effectiveness of intravenous gamma globulin (IV-Ig) and hydroxychloroquine (Plaquenil) in reducing CHB-risk. Evidence for both is, however, inconclusive, and studies are biased in favor of hydroxychloroquine and against IV-Ig. Based on the review of the literature, current evidence of effectiveness for any treatment has to be judged as insufficient. Among the available treatment options, some considerations favor IV-Ig over hydroxychloroquine or, alternatively, suggest treatment with IV-Ig periconceptionally and into early gestation, with hydroxychloroquine added or replacing IV-Ig at approximately 10weeks gestational age. Benefits for the utilization of steroid drugs are unclear. Since no treatment can be considered as established, prevention of CHB in offspring should be considered experimental, and performed under appropriate study conditions.