RT Journal Article
SR Electronic
T1 Anti-52 kDa Ro, anti-60 kDa Ro, and anti-La antibody profiles in neonatal lupus.
JF The Journal of Rheumatology
JO J Rheumatol
FD The Journal of Rheumatology
SP 2480
OP 2487
VO 31
IS 12
A1 Patrick Gordon
A1 Munther A Khamashta
A1 Eric Rosenthal
A1 John M Simpson
A1 Gurleen Sharland
A1 Antonio Brucato
A1 Franco Franceschini
A1 Katrien De Bosschere
A1 Lydie Meheus
A1 Pier Luigi Meroni
A1 Graham R V Hughes
A1 Jill Buyon
YR 2004
UL http://www.jrheum.org/content/31/12/2480.abstract
AB OBJECTIVE: Studies suggest that anti-52 kDa Ro antibodies are more sensitive and specific than anti-60 kDa Ro antibodies for neonatal lupus. However, these studies mainly used immunoblot or ELISA using recombinant protein, which have poor sensitivity for anti-60 kDa Ro antibodies. In addition, the control patients were not disease matched. We reassessed the sensitivity and specificity of anti-52 kDa Ro, anti-60 kDa Ro, and anti-La, addressing these limitations. METHODS AND RESULTS: To assess sensitivity, 125 mothers of children with neonatal lupus (NLM) were recruited. All maternal sera were assessed using a commercial line immunoassay that uses natural 60 kDa Ro protein (Inno-Lia ANA Update, Innogenetics NV, Gent, Belgium). By this method, 96% of the sera had antibodies to 60 kDa Ro, 86% to 52 kDa Ro, and 78% to 48 kDa La. Immunoblot of 65 NLM showed significantly fewer positive results for anti-60 kDa Ro (p < 0.001) and anti-52 kDa Ro (p < 0.05). Sensitivity of the 3 antibodies was assessed in the symptomatic mothers of children with congenital heart block (CHB) (78 women) and disease matched controls with unaffected children (65 women) using Inno-Lia ANA Update. The sensitivity of each antibody was compared by multiple logistic regression to adjust for maternal disease. There was no significant difference between the groups for 60 kDa Ro or for anti-52 kDa Ro antibody. However, there was a significant difference for the anti-La antibody (p = 0.001), with an odds ratio of 3.59. This translates to an increase in risk from a published 2% for CHB in an anti-Ro-positive mother to 3.1% if the woman is also anti-La antibody-positive, and to a decrease in risk to 0.9% if anti-La-negative. CONCLUSION: Contrary to previous reports, 52 kDa Ro as detected by Inno-Lia ANA Update is not more specific for or frequent in CHB than 60 kDa Ro. However, the presence of anti-La antibodies significantly increases the risk for CHB.