Persistently active interferon-γ pathway and expansion of T-bet+ B cells in a subset of patients with childhood-onset systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease causing significant morbidity and mortality, despite important improvements in its management in the last decades. The objective of this work is to investigate the role of IFN-γ in the pathogenesis of childhood-onset systemic lupus erythematosus (cSLE), evaluating the crosstalk between IFN-α and IFN-γ and the expression of T-bet, a transcription factor induced by IFN-γ, in B cells of patients with cSLE. Expression levels of both IFN-α and IFN-γ-induced genes were upregulated in patients with cSLE. We found increased serum levels of CXCL9 and CXCL10 in patients with cSLE. Type I IFN score decreased with initiation of immunosuppressive treatment; conversely, type II IFN score and levels of CXCL9 were not significantly affected by immunosuppressive treatment. Type II IFN score and CXCL9 were significantly higher in patients with lupus nephritis. We observed the expansion of a population of naïve B cells expressing T-bet in a cluster of patients with cSLE. IFN-γ, but not IFN-α, induced the expression of T-bet in B cells. Our data suggest that IFN-γ is hyperactive in cSLE, especially in patients with lupus nephritis, and it is not modulated by therapy. Our data reinforce the potential of IFN-γ as a therapeutic target in SLE.

Genetics of Neonatal Lupus Erythematosus Risk and Specific Manifestations.

OBJECTIVE: Neonatal lupus erythematosus (NLE) is a passively acquired autoimmune disease of infants born to anti-Ro and/or La autoantibody positive mothers. Genetics may impact NLE risk. We analyzed the genetics of infants and anti-Ro antibody positive mothers, with NLE and NLE specific manifestations. METHODS: Infants and mothers from a tertiary care clinic underwent genotyping on the Global Screening Array. We created additive non-HLA and HLA polygenic risk scores (PRSs) for systemic lupus erythematosus (SLE), from one of the largest genome wide association studies. Outcomes were any NLE manifestations, cardiac NLE, and cutaneous NLE. We tested the association between SLE-PRSs in the infant, mother, and the PRS difference between the mother and infant with NLE outcomes, in logistic regression and generalized linear mixed models (Bonferroni P<0.02). We also performed HLA-wide analyses for the outcomes (P<5.00x10-8). RESULTS: The study included 332 infants, 270 anti-Ro antibody positive mothers, and 253 mother-infant pairs. A large proportion of mothers (40.3%) and infants (41.3%) were European, and 50.0% of infants were female. More than half of the infants had NLE (53.0%), including 7.2% with cardiac NLE and 11.7% with cutaneous NLE. We did not identify significant associations between infant, maternal, or maternal-infant PRSs and any NLE outcomes. HLA-wide analyses did not identify NLE risk alleles. CONCLUSION: In a multiethnic cohort of infants and anti-Ro antibody positive mothers, we did not identify a significant association between SLE genetics and risk of NLE outcomes.

Transmission disequilibrium analysis of whole genome data in childhood-onset systemic lupus erythematosus.

Childhood-onset systemic lupus erythematosus (cSLE) patients are unique, with hallmarks of Mendelian disorders (early-onset and severe disease) and thus are an ideal population for genetic investigation of SLE. In this study, we use the transmission disequilibrium test (TDT), a family-based genetic association analysis that employs robust methodology, to analyze whole genome sequencing data. We aim to identify novel genetic associations in an ancestrally diverse, international cSLE cohort. Forty-two cSLE patients and 84 unaffected parents from 3 countries underwent whole genome sequencing. First, we performed TDT with single nucleotide variant (SNV)-based (common variants) using PLINK 1.9, and gene-based (rare variants) analyses using Efficient and Parallelizable Association Container Toolbox (EPACTS) and rare variant TDT (rvTDT), which applies multiple gene-based burden tests adapted for TDT, including the burden of rare variants test. Applying the GWAS standard threshold (5.0 × 10-8) to common variants, our SNV-based analysis did not return any genome-wide significant SNVs. The rare variant gene-based TDT analysis identified many novel genes significantly enriched in cSLE patients, including HNRNPUL2, a DNA repair protein, and DNAH11, a ciliary movement protein, among others. Our approach identifies several novel SLE susceptibility genes in an ancestrally diverse childhood-onset lupus cohort.

High-sensitivity cardiac troponin T in infants exposed to anti-Ro antibodies.

OBJECTIVES: Cardiac involvement in neonatal lupus erythematosis (NLE) can present as myocarditis/endocardial fibroelastosis (EFE). It is unknown whether high-sensitivity cardiac troponin T (hs-cTnT) is useful in identifying subclinical myocardial inflammation in infants exposed prenatally to anti-Ro antibodies. This study reports hs-cTnT levels in infants exposed to anti-Ro antibodies with/without cardiac NLE and reports cardiac MRI (CMR) findings in a subset of these children. METHODS: The study included 45 consecutive infants exposed prenatally to anti-Ro antibodies with (n = 7) or without (n = 38) cardiac NLE, who were seen at the SickKids NLE Clinic between 2012 and 2014. Hs-cTnT levels were measured at least once, and those infants with values of ≥30 ng/l were offered the opportunity to undergo CMR. Descriptive statistics were performed. RESULTS: Of 38 infants without cardiac NLE, 25 had a hs-cTnT level of ≥30 ng/l (including 1 of >113 ng/l); of these, 8 underwent CMR (all without myocarditis/EFE). All 7 infants with cardiac NLE had at least one hs-cTnT level of ≥30 ng/l, but only 2/7 had a level of >113 ng/l; 4/7 infants with cardiac NLE had CMR (all without myocarditis/EFE); 6/7 infants with cardiac NLE had their steroid treatment adjusted based on the trend in their hs-cTnT levels. CONCLUSION: Only 3/45 anti-Ro antibodies-exposed infants had hs-cTnT values outside the reference range reported in healthy infants. None of 12 infants who had CMR had subclinical myocarditis/EFE. Routine measurement of hs-cTnT in every anti-Ro antibody-exposed infant is not indicated. Further studies are needed to define the role of hs-cTnT as a biomarker for cardiac NLE.

Genetics of osteonecrosis in children and adults with systemic lupus erythematosus.

OBJECTIVES: Genetics plays an important role in SLE risk, as well as osteonecrosis (ON), a significant and often debilitating complication of SLE. We aimed to identify genetic risk loci for ON in people with childhood-onset (cSLE) and adult-onset (aSLE) SLE. METHODS: We enrolled participants from two tertiary care centres who met classification criteria for SLE. Participants had prospectively collected clinical data and were genotyped on a multiethnic array. Un-genotyped single nucleotide polymorphisms (SNPs) were imputed, and ancestry was inferred using principal components (PCs). Our outcome was symptomatic ON confirmed by imaging. We completed time-to-ON and logistic regression of ON genome-wide association studies (GWASs) with covariates for sex, age of SLE diagnosis, five PCs for ancestry, corticosteroid use and selected SLE manifestations. We conducted separate analyses for cSLE and aSLE and meta-analysed results using inverse-variance weighting. Genome-wide significance was P < 5 × 10-8. RESULTS: The study included 940 participants with SLE, 87% female and 56% with cSLE. ON was present in 7.6% (n = 71). Median age of SLE diagnosis was 16.9 years (interquartile range [IQR]: 13.5, 29.3), with median follow-up of 8.0 years (IQR: 4.2, 15.7). Meta-GWAS of cSLE and aSLE time-to-ON of 4 431 911 SNPs identified a significant Chr.2 SNP, rs34118383 (minor allele frequency = 0.18), intronic to WIPF1 (hazard ratio = 3.2 [95% CI: 2.2, 4.8]; P = 1.0 × 10-8). CONCLUSION: We identified an intronic WIPF1 variant associated with a 3.2 times increased hazard for ON (95% CI: 2.2, 4.8; P = 1.0 × 10-8) during SLE follow-up, independent of corticosteroid exposure. The effect of the SNP on time-to-ON was similar in cSLE and aSLE. This novel discovery represents a potential ON risk locus. Our results warrant replication.

Genetics of longitudinal kidney function in children and adults with systemic lupus erythematosus.

OBJECTIVES: Genome-wide association studies (GWAS) have identified loci associated with estimated glomerular filtration rate (eGFR). Few LN risk loci have been identified to date. We tested the association of SLE and eGFR polygenic risk scores (PRS) with repeated eGFR measures from children and adults with SLE. METHODS: Patients from two tertiary care lupus clinics that met ≥4 ACR and/or SLICC criteria for SLE were genotyped on the Illumina MEGA or Omni1-Quad arrays. PRSs were calculated for SLE and eGFR, using published weighted GWA-significant alleles. eGFR was calculated using the CKD-EPI and Schwartz equations. We tested the effect of eGFR- and SLE-PRSs on eGFR mean and variance, adjusting for age at diagnosis, sex, ancestry, follow-up time, and clinical event flags. RESULTS: We included 1158 SLE patients (37% biopsy-confirmed LN) with 36 733 eGFR measures over a median of 7.6 years (IQR: 3.9-15.3). LN was associated with lower within-person mean eGFR [LN: 93.8 (s.d. 26.4) vs non-LN: 101.6 (s.d. 17.7) mL/min per 1.73 m2; P < 0.0001] and higher variance [LN median: 157.0 (IQR: 89.5, 268.9) vs non-LN median: 84.9 (IQR: 46.9, 138.2) (mL/min per 1.73 m2)2; P < 0.0001]. Increasing SLE-PRSs were associated with lower mean eGFR and greater variance, while increasing eGFR-PRS was associated with increased eGFR mean and variance. CONCLUSION: We observed significant associations between SLE and eGFR PRSs and repeated eGFR measurements, in a large cohort of children and adults with SLE. Longitudinal eGFR may serve as a powerful alternative outcome to LN categories for discovery of LN risk loci.

Evaluation of self-report screening measures in the detection of depressive and anxiety disorders among children and adolescents with systemic lupus erythematosus.

BACKGROUND: There are no validated screening measures for depressive or anxiety disorders in childhood Systemic Lupus Erythematosus (cSLE). We investigated cross-sectionally (1) the prevalence of depressive and anxiety disorder in cSLE. (2) the validity of the Centre for Epidemiologic Studies Depression Scale for Children (CES-DC) and the Screen for Childhood Anxiety and Related Disorders (SCARED) measures in identifyingthese disorders. METHODS: Participants 8-18 years with cSLE/incipient cSLE completed CES-DC, SCARED, and Quality OfMy Life (QOML) measures. Parents completed the SCARED-Parent measure. Diagnosis was by gold-standard psychiatric interview and determined prevalence of psychiatric disorder. Receiver Operating Characteristics Area under the Curve (ROCAUC) evaluated screening measure diagnostic performance. RESULTS: Ofseventy-two parent-child dyads, 56 interviews were completed. Mean screen scores were: CES-DC = 15 (range 1-49, SD 12), SCARED-C = 22 (range 2-61, SD 14), SCARED-P = 13 (range 0-36, SD 8). Depressive disorder screen positivity (CES-DC ≥ 15) was 35% (vs. prevalence 5%). Anxiety disorder screen positivity (SCARED ≥ 25) was 39% (vs. prevalence 16%). CES-DC ROCAUC = 0.98 and SCARED-C ROCAUC = 0.7 (cut-points 38 and 32 respectively). CONCLUSIONS: Diagnostic thresholds for depressive and anxiety disorderscreening measures are high for both CES-DC and SCARED-C in cSLE. Brief focused interview should follow to determine whether psychiatric evaluation is warranted.

Effects of Transplacental Dexamethasone Therapy on Fetal Immune-Mediated Complete Heart Block.

INTRODUCTION: Antibody-mediated complete atrioventricular block (CAVB) is considered irreversible. We sought to examine the effects of transplacental steroids on fetal AV conduction. METHODS: Fifty-nine fetuses diagnosed with CAVB at our center from 1996 to 2018 were reviewed. Routine dexamethasone administration to birth was used to limit cardiac inflammatory damage. Restoration of fetal AV conduction was classified as "unexpected" treatment response. RESULTS: CAVB resolved in 5/29 (17%) fetuses first treated ≤24-week gestation with 8 mg/day of dexamethasone, when compared with 0/30 (0%) when treatment was initiated later and/or at a starting dose of 4 mg/day (odds ratio 13.69; 95% confidence interval 0.72-260.13; p = 0.024). Treatment response was also associated with a faster ventricular rate at diagnosis (median [range]: 80 [60-97] beats per minute [bpm] vs. 58 [38-92] bpm; p = 0.0036). CAVB reappeared in all 5 responders either prenatally (n = 1) or postnatally before (n = 3) or after (n = 1) the first year of life. When compared with infants with treatment-resistant CAVB (median follow-up 10.3 years), responders (median follow-up 12.3 years) required postnatal pacing less frequent (2/5 [40%] vs. 45/49 [92%]; p = 0.013). CONCLUSIONS: In a subgroup of CAVB fetuses, dexamethasone transiently restored AV conduction. This was associated with a lower rate of postnatal pacing when compared with nonresponders.

Association of systemic lupus erythematosus (SLE) genetic susceptibility loci with lupus nephritis in childhood-onset and adult-onset SLE.

OBJECTIVE: LN is one of the most common and severe manifestations of SLE. Our aim was to test the association of SLE risk loci with LN risk in childhood-onset SLE (cSLE) and adult-onset SLE (aSLE). METHODS: Two Toronto-based tertiary care SLE cohorts included cSLE (diagnosed <18 years) and aSLE patients (diagnosed ⩾18 years). Patients met ACR and/or SLICC SLE criteria and were genotyped on the Illumina Multi-Ethnic Global Array or Omni1-Quad arrays. We identified those with and without biopsy-confirmed LN. HLA and non-HLA additive SLE risk-weighted genetic risk scores (GRSs) were tested for association with LN risk in logistic models, stratified by cSLE/aSLE and ancestry. Stratified effect estimates were meta-analysed. RESULTS: Of 1237 participants, 572 had cSLE (41% with LN) and 665 had aSLE (30% with LN). Increasing non-HLA GRS was significantly associated with increased LN risk [odds ratio (OR) = 1.26; 95% CI 1.09, 1.46; P = 0.0006], as was increasing HLA GRS in Europeans (OR = 1.55; 95% CI 1.07, 2.25; P = 0.03). There was a trend for stronger associations between both GRSs and LN risk in Europeans with cSLE compared with aSLE. When restricting cases to proliferative LN, the magnitude of these associations increased for both the non-HLA (OR = 1.30; 95% CI 1.10, 1.52; P = 0.002) and HLA GRS (OR = 1.99; 95% CI 1.29, 3.08; P = 0.002). CONCLUSION: We observed an association between known SLE risk loci and LN risk in children and adults with SLE, with the strongest effect observed among Europeans with cSLE. Future studies will include SLE-risk single nucleotide polymorphisms specific to non-European ancestral groups and validate findings in an independent cohort.

Cutaneous sequelae in neonatal lupus: A retrospective cohort study.

BACKGROUND: Cutaneous eruptions in neonatal lupus erythematosus (NLE) are thought to be self-resolving. Limited literature suggests cutaneous changes may persist. OBJECTIVE: To characterize cutaneous residua in NLE and identify predictors for their development. METHODS: A retrospective cohort study of patients with cutaneous NLE born between January 1980 and May 2017 was performed. Primary outcome was the proportion of patients with cutaneous residua. Secondary outcomes included associations/predictors of sequelae. RESULTS: At the last follow-up, at a mean age of 4 years (range, 0.5-18.7 years), 34% of 106 patients had cutaneous sequelae, 13% had telangiectasia, 17% had dyspigmentation, and 9% had atrophic scarring. Scarring at the last follow-up was significantly associated with the presence of skin lesions at birth (P < .001). LIMITATIONS: This study was limited by the retrospective design, short follow-up duration in a subset of patients, and small sample size. CONCLUSION: Cutaneous NLE can exhibit long-term cutaneous residua. These findings underlie the importance of accurate diagnosis, long-term monitoring, and appropriate counseling.

A comparison between childhood and adult onset systemic lupus erythematosus adjusted for ethnicity from the 1000 Canadian Faces of Lupus Cohort.

OBJECTIVE: Childhood-onset SLE (cSLE) manifests differently than adult-onset SLE (aSLE). This study determined whether ethnic differences contribute to the differences in clinical presentation between the two groups. METHODS: This cross-sectional study used data from a multi-centred registry from eight adult and four paediatric Canadian centres gathered at study entry. We compared the frequency of clinical manifestations and autoantibodies between aSLE and cSLE. For those with a significant difference, a multivariable logistic regression was performed, adjusting for ethnicity, SLE onset (cSLE vs aSLE), disease duration and centre. Disease activity and damage between aSLE and cSLE were compared after stratifying by disease duration. RESULTS: Of 552 aSLE subjects, 502 (90.9%) were female and 381 (69.0%) were Caucasian. Mean age at diagnosis was 37.0 ± 13.6 years and disease duration 10.9 ± 9.6 years. Of 276 cSLE subjects, 231 (83.7%) were female and 101 (36.6%) were Caucasian. Mean age at diagnosis was 12.7 ± 3.3 years and disease duration 5.6 ± 8.2 years. In multivariable regression analysis, aSLE was associated with decreased odds of having a neurologic disorder (odds ratio = 0.49) and increased odds of having aCL antibodies (odds ratio = 1.85). Disease activity and damage accrual scores were higher in aSLE than cSLE within the same disease duration strata, although the differences were not clinically significant. Ethnicity was not associated with any differences in clinical manifestations or autoantibody frequency between aSLE and cSLE. CONCLUSIONS: Although a crude comparison of aSLE and cSLE yielded several differences in clinical symptoms and autoantibodies, this difference was not attributable to ethnic differences between aSLE and cSLE.

Serologic features of cohorts with variable genetic risk for systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disease with genetic, hormonal, and environmental influences. In Western Europe and North America, individuals of West African descent have a 3-4 fold greater incidence of SLE than Caucasians. Paradoxically, West Africans in sub-Saharan Africa appear to have a low incidence of SLE, and some studies suggest a milder disease with less nephritis. In this study, we analyzed sera from African American female SLE patients and four other cohorts, one with SLE and others with varying degrees of risk for SLE in order to identify serologic factors that might correlate with risk of or protection against SLE. METHODS: Our cohorts included West African women with previous malaria infection assumed to be protected from development of SLE, clinically unaffected sisters of SLE patients with high risk of developing SLE, healthy African American women with intermediate risk, healthy Caucasian women with low risk of developing SLE, and women with a diagnosis of SLE. We developed a lupus risk index (LRI) based on titers of IgM and IgG anti-double stranded DNA antibodies and levels of C1q. RESULTS: The risk index was highest in SLE patients; second highest in unaffected sisters of SLE patients; third highest in healthy African-American women and lowest in healthy Caucasian women and malaria-exposed West African women. CONCLUSION: This risk index may be useful in early interventions to prevent SLE. In addition, it suggests new therapeutic approaches for the treatment of SLE.

Effect of in utero hydroxychloroquine exposure on the development of cutaneous neonatal lupus erythematosus.

OBJECTIVE: Cutaneous neonatal lupus (cNL) occurs in possibly 5%-16% of anti-Ro±anti-La antibody-exposed infants. Data suggest in utero exposure to hydroxychloroquine (HCQ) may prevent cardiac NL. The aim was to assess whether in utero exposure to HCQ decreases the risk of cNL and/or delays onset. METHODS: A multicentre case-control study was performed with 122 cNL cases and 434 controls born to women with a rheumatological disease who had documentation of maternal anti-Ro±anti-La antibodies at pregnancy and confirmation of medication use and the child's outcome. A secondary analysis was performed on 262 cNL cases, irrespective of maternal diagnosis, to determine if HCQ delayed time to cNL onset. RESULTS: Twenty (16%) cNL cases were exposed to HCQ compared with 146 (34%) controls (OR 0.4 (95% CI 0.2 to 0.6); p<0.01). Exposure to HCQ was associated with a reduced risk of cNL; exposure to anti-La antibody and female gender were associated with an increased risk of cNL. Exposure to HCQ remained significantly associated with a reduced cNL risk in the analyses limited to mothers with systemic lupus erythematosus and those who developed rash ≤1 month. When analysing all 262 cNL cases, HCQ-exposed infants were older (6.0 (95% CI 5.7 to 6.3) weeks) at cNL onset versus HCQ-non-exposed infants (4.4 (95% CI 3.9 to 5.0) weeks), but the difference was not statistically significant (p=0.21). CONCLUSION: Exposure to HCQ was associated with a reduced risk of cNL. Among cNL cases, those exposed to HCQ tend to have later onset of rash. Both findings suggest a protective effect of HCQ on cNL.

Subcutaneous golimumab for children with active polyarticular-course juvenile idiopathic arthritis: results of a multicentre, double-blind, randomised-withdrawal trial.

OBJECTIVE: This report aims to determine the safety, pharmacokinetics (PK) and efficacy of subcutaneous golimumab in active polyarticular-course juvenile idiopathic arthritis (polyJIA). METHODS: In this three-part randomised double-blinded placebo-controlled withdrawal trial, all patients received open-label golimumab (30 mg/m2 of body surface area; maximum: 50 mg/dose) every 4 weeks together with weekly methotrexate during Part 1 (weeks 0-16). Patients with at least 30% improvement per American College of Rheumatology Criteria for JIA (JIA ACR30) in Part 1 entered the double-blinded Part 2 (weeks 16-48) after 1:1 randomisation to continue golimumab or start placebo. In Part 3, golimumab was continued or could be restarted as in Part 1. The primary outcome was JIA flares in Part 2; secondary outcomes included JIA ACR50/70/90 responses, clinical remission, PK and safety. RESULTS: Among 173 patients with polyJIA enrolled, 89.0% (154/173) had a JIA ACR30 response and 79.2%/65.9%/36.4% demonstrated JIA ACR50/70/90 responses in Part 1. At week 48, the primary endpoint was not met as treatment groups had comparable JIA flare rates (golimumab vs placebo: 32/78=41% vs 36/76=47%; p=0.41), and rates of clinical remission were comparable (golimumab vs placebo: 10/78=12.8% vs 9/76=11.8%). Adverse event and serious adverse event rates were similar in the treatment groups during Part 2. Injection site reactions occurred with <1% of all injections. PK analysis confirmed adequate golimumab dosing for polyJIA. CONCLUSION: Although the primary endpoint was not met, golimumab resulted in rapid, clinically meaningful, improvement in children with active polyJIA. Golimumab was well tolerated, and no unexpected safety events occurred. CLINICAL TRIAL REGISTRATION: NCT01230827; Results.

Improved diagnostic yield compared with targeted gene sequencing panels suggests a role for whole-genome sequencing as a first-tier genetic test.

PurposeGenetic testing is an integral diagnostic component of pediatric medicine. Standard of care is often a time-consuming stepwise approach involving chromosomal microarray analysis and targeted gene sequencing panels, which can be costly and inconclusive. Whole-genome sequencing (WGS) provides a comprehensive testing platform that has the potential to streamline genetic assessments, but there are limited comparative data to guide its clinical use.MethodsWe prospectively recruited 103 patients from pediatric non-genetic subspecialty clinics, each with a clinical phenotype suggestive of an underlying genetic disorder, and compared the diagnostic yield and coverage of WGS with those of conventional genetic testing.ResultsWGS identified diagnostic variants in 41% of individuals, representing a significant increase over conventional testing results (24%; P = 0.01). Genes clinically sequenced in the cohort (n = 1,226) were well covered by WGS, with a median exonic coverage of 40 × ±8 × (mean ±SD). All the molecular diagnoses made by conventional methods were captured by WGS. The 18 new diagnoses made with WGS included structural and non-exonic sequence variants not detectable with whole-exome sequencing, and confirmed recent disease associations with the genes PIGG, RNU4ATAC, TRIO, and UNC13A.ConclusionWGS as a primary clinical test provided a higher diagnostic yield than conventional genetic testing in a clinically heterogeneous cohort.

Prenatal exposure to antimalarials decreases the risk of cardiac but not non-cardiac neonatal lupus: a single-centre cohort study.

Objective: Recent studies have suggested that prenatal exposure to HCQ reduces the risk of cardiac neonatal lupus. The aim of this study is to assess if maternal intake of antimalarials (AMs) throughout pregnancy lowered the risk of cardiac and non-cardiac neonatal lupus. Methods: Consecutive children seen between 1 January 1984 to 1 October 2013 born to women with a CTD and positive anti-Ro and/or anti-La antibodies were eligible for this single-centre retrospective cohort study. A total of 315 individuals were screened and 268 participants were included. Exposure to AMs was defined as HCQ or chloroquine throughout pregnancy. Outcomes were cardiac and non-cardiac neonatal lupus. Frequentist and Bayesian analyses were performed. We hypothesized that prenatal AM exposure would decrease the risk of cardiac but not non-cardiac neonatal lupus. Results: A total of 268 pregnancies were included; 73 were exposed to AMs throughout pregnancy. Ninety-nine children developed neonatal lupus, 117 remained unaffected and 52 children did not develop cardiac neonatal lupus but could not be categorized as unaffected since their full non-cardiac neonatal lupus status was unknown. Logistic regression suggested a protective effect of AM on cardiac neonatal lupus, but results were not statistically significant [odds ratio (OR) 0.21; P = 0.07]. Bayesian analysis showed that the probability of obtaining a protective effect (OR < 1.0) for cardiac neonatal lupus was significant (98.7%). The effect of AMs on non-cardiac neonatal lupus was not significant (OR 0.78; P = 0.21). Conclusion: In this large single-centre cohort study, exposure to AMs throughout pregnancy was associated with a decreased probability of developing cardiac but not non-cardiac neonatal lupus.