Faculty Bibliography

Background: Because systemic lupus erythematosus (SLE) affects women of reproductive age, pregnancy is a major concern. Objective: To identify predictors of adverse pregnancy outcomes (APOs) in patients with inactive or stable active SLE. Design: Prospective cohort. Setting: Multicenter. Patients: 385 patients (49% non-Hispanic white; 31% with prior nephritis) with SLE in the PROMISSE study. Exclusion criteria were urinary protein-creatinine ratio greater than 1000 mg/g, creatinine level greater than 1.2 mg/dL, prednisone use greater than 20 mg/d, and multifetal pregnancy. Measurements: APOs included fetal or neonatal death; birth before 36 weeks due to placental insufficiency, hypertension, or preeclampsia; and small-for-gestational-age (SGA) neonate (birthweight below the fifth percentile). Disease activity was assessed with the Systemic Lupus Erythematosus Pregnancy Disease Activity Index and the Physician's Global Assessment (PGA). Results: APOs occurred in 19.0% (95% CI, 15.2% to 23.2%) of pregnancies; fetal death occurred in 4%, neonatal death occurred in 1%, preterm delivery occurred in 9%, and SGA neonate occurred in 10%. Severe flares in the second and third trimesters occurred in 2.5% and 3.0%, respectively. Baseline predictors of APOs included presence of lupus anticoagulant (LAC) (odds ratio [OR], 8.32 [CI, 3.59 to 19.26]), antihypertensive use (OR, 7.05 [CI, 3.05 to 16.31]), PGA score greater than 1 (OR, 4.02 [CI, 1.84 to 8.82]), and platelet count (OR, 1.33 [CI, 1.09 to 1.63] per decrease of 50 x 109 cells/L). Non-Hispanic white race was protective (OR, 0.45 [CI, 0.24 to 0.84]). Maternal flares, higher disease activity, and smaller increases in C3 level later in pregnancy also predicted APOs. Among women without baseline risk factors, the APO rate was 7.8%. For those who either were LAC-positive or were LAC-negative but nonwhite or Hispanic and using antihypertensives, the APO rate was 58.0% and fetal or neonatal mortality was 22.0%. Limitation: Patients with high disease activity were excluded. Conclusion: In pregnant patients with inactive or stable mild or moderate SLE, severe flares are infrequent, and absent specific risk factors, outcomes are favorable. Primary Funding Source: National Institutes of Health.

BACKGROUND: Only 2% of mothers positive for anti-SSA/Ro (Ro) antibodies have children with congenital heart block (CHB). This study aimed to determine whether reactivity with p305, an epitope within the alpha1G T-type calcium channel, confers added risk over anti-Ro antibodies. METHODS AND RESULTS: Using sera from anti-Ro-exposed pregnancies resulting in offspring with CHB, no disease but CHB-sibling, and no disease and no CHB-sibling, as well as disease (lupus without anti-Ro) and healthy controls, reactivities were determined for binding to Ro60, p305, and an epitope within Ro60, p133-Ro60, which shares structural properties with p305, including key amino acids and an alpha-helical structure. Candidate peptides were further evaluated in an in vitro model that assessed the binding of maternal antibodies to apoptotic cells. In anti-Ro-positive mothers, anti-p305 autoantibodies (>3 SD above healthy controls) were detected in 3/59 (5%) CHB pregnancies, 4/30 (13%) unaffected pregnancies with a CHB-sibling, and 0/42 (0%) of unaffected pregnancies with no CHB-sibling. For umbilical bloods (61 CHB, 41 healthy with CHB sibling), no association of anti-p305 with outcome was detected; however, overall levels of anti-p305 were elevated compared to mothers during pregnancy in all groups studied. For anti-p133-Ro60, reactivity paralleled that of anti-p305. In the screen employing apoptotic cells, p133-Ro60, but not p305, significantly attenuated the binding of immunoglobulin G isolated from a mother whose child had CHB (42.1% reduced to 13.9%, absence/presence of p133-Ro60, respectively, P<0.05). CONCLUSIONS: These data suggest that anti-p305 is not a robust maternal marker for assessing increased risk of CHB during an anti-SSA/Ro pregnancy.

Autoimmune congenital heart block (CHB) is an immune-mediated acquired disease that is associated with the placental transference of maternal antibodies specific for Ro and La autoantigens. The disease develops in a fetal heart without anatomical abnormalities that could otherwise explain the block, and which is usually diagnosed in utero, but also at birth or within the neonatal period. Autoantibody-mediated damage of fetal conduction tissues causes inflammation and fibrosis and leads to blockage of signal conduction at the atrioventricular (AV) node. Irreversible complete AV block is the principal cardiac manifestation of CHB, although some babies might develop other severe cardiac complications, such as endocardial fibroelastosis or valvular insufficiency, even in the absence of cardiac block. In this Review, we discuss the epidemiology, classification and management of women whose pregnancies are affected by autoimmune CHB, with a particular focus on the autoantibodies associated with autoimmune CHB and how we should test for these antibodies and diagnose this disease. Without confirmed effective preventive or therapeutic strategies and further research on the aetiopathogenic mechanisms, autoimmune CHB will remain a severe life-threatening disorder.

OBJECTIVE: Anti-C1q has been associated with systemic lupus erythematosus (SLE) and lupus nephritis in previous studies. We studied anti-C1q specificity for SLE (vs rheumatic disease controls) and the association with SLE manifestations in an international multicenter study. METHODS: Information and blood samples were obtained in a cross-sectional study from patients with SLE (n = 308) and other rheumatologic diseases (n = 389) from 25 clinical sites (84% female, 68% Caucasian, 17% African descent, 8% Asian, 7% other). IgG anti-C1q against the collagen-like region was measured by ELISA. RESULTS: Prevalence of anti-C1q was 28% (86/308) in patients with SLE and 13% (49/389) in controls (OR = 2.7, 95% CI: 1.8-4, p < 0.001). Anti-C1q was associated with proteinuria (OR = 3.0, 95% CI: 1.7-5.1, p < 0.001), red cell casts (OR = 2.6, 95% CI: 1.2-5.4, p = 0.015), anti-dsDNA (OR = 3.4, 95% CI: 1.9-6.1, p < 0.001) and anti-Smith (OR = 2.8, 95% CI: 1.5-5.0, p = 0.01). Anti-C1q was independently associated with renal involvement after adjustment for demographics, ANA, anti-dsDNA and low complement (OR = 2.3, 95% CI: 1.3-4.2, p < 0.01). Simultaneously positive anti-C1q, anti-dsDNA and low complement was strongly associated with renal involvement (OR = 14.9, 95% CI: 5.8-38.4, p < 0.01). CONCLUSIONS: Anti-C1q was more common in patients with SLE and those of Asian race/ethnicity. We confirmed a significant association of anti-C1q with renal involvement, independent of demographics and other serologies. Anti-C1q in combination with anti-dsDNA and low complement was the strongest serological association with renal involvement. These data support the usefulness of anti-C1q in SLE, especially in lupus nephritis.

OBJECTIVE:To compare the performance characteristics of cell-bound complement (C4d) activation products (CBCAPS) on erythrocyte (EC4d) and B cells (BC4d) with antibodies to double-stranded DNA (anti-dsDNA) and complement C3 and C4 in systemic lupus erythematosus (SLE). METHODS:The study enrolled 794 subjects consisting of 304 SLE and a control group consisting of 285 patients with other rheumatic diseases and 205 normal individuals. Anti-dsDNA and other autoantibodies were measured using solid-phase immunoassays while EC4d and BC4d were determined using flow cytometry. Complement proteins were determined using immunoturbidimetry. Disease activity in SLE was determined using a non-serological Systemic Lupus Erythematosus Disease Activity Index SELENA Modification. A two-tiered methodology combining CBCAPS with autoantibodies to cellular and citrullinated antigens was also developed. Statistical analyses used area under receiver operating characteristic curves and calculations of area under the curve (AUC), sensitivity and specificity. RESULTS:AUC for EC4d (0.82±0.02) and BC4d (0.84±0.02) was higher than those yielded by C3 (0.73±0.02) and C4 (0.72±0.02) (p<0.01). AUC for CBCAPS was also higher than the AUC yielded by anti-dsDNA (0.79±0.02), but significance was only achieved for BC4d (p<0.01). The combination of EC4d and BC4d in multivariate testing methodology with anti-dsDNA and autoantibodies to cellular and citrullinated antigens yielded 80% sensitivity for SLE and specificity ranging from 70% (Sjogren's syndrome) to 92% (rheumatoid arthritis) (98% vs. normal). A higher proportion of patients with SLE with higher levels of disease activity tested positive for elevated CBCAPS, reduced complement and anti-dsDNA (p<0.03). CONCLUSIONS:CBCAPS have higher sensitivity than standard complement and anti-dsDNA measurements, and may help with the differential diagnosis of SLE in combination with other autoantibodies.