Anti-ribosomal P antibody: a multicenter study in childhood-onset systemic lupus erythematosus patients.

Objectives Anti-ribosomal P protein (anti-P) autoantibodies are highly specific for systemic lupus erythematosus (SLE). However, the evaluation of this autoantibody in childhood-onset SLE (cSLE) populations has been limited to a few small series, hampering the interpretation of the clinical and laboratorial associations. Therefore, the objective of this multicenter cohort study was to evaluate demographic, clinical/laboratorial features, and disease damage score in cSLE patients with and without the presence of anti-P antibody. Methods This was a retrospective multicenter study performed in 10 pediatric rheumatology services of São Paulo state, Brazil. Anti-P antibodies were measured by ELISA in 228 cSLE patients. Results Anti-P antibodies were observed in 61/228 (27%) cSLE patients. Frequencies of cumulative lymphadenopathy (29% vs. 15%, p = 0.014), acute confusional state (13% vs. 5%, p = 0.041), mood disorder (18% vs. 8%, p = 0.041), autoimmune hemolytic anemia (34% vs. 15%, p = 0.001), as well as presence of anti-Sm (67% vs. 40%, p = 0.001), anti-RNP (39% vs. 21%, p = 0.012) and anti-Ro/SSA antibodies (43% vs. 25%, p = 0.016) were significantly higher in cSLE patients with anti-P antibodies compared to those without these autoantibodies. A multiple regression model revealed that anti-P antibodies were associated with autoimmune hemolytic anemia (odds ratio (OR) = 2.758, 95% confidence interval (CI): 1.304-5.833, p = 0.008) and anti-Sm antibody (OR = 2.719, 95% CI: 1.365-5.418, p = 0.004). The SLICC/ACR damage index was comparable in patients with and without anti-P antibodies ( p = 0.780). Conclusions The novel association of anti-P antibodies and autoimmune hemolytic anemia was evidenced in cSLE patients and further studies are necessary to determine if anti-P titers may vary with this hematological manifestation.

Subclinical left ventricular dysfunction in childhood-onset systemic lupus erythematosus: a two-dimensional speckle-tracking echocardiographic study.

OBJECTIVES: The main purpose of the study was to investigate left ventricular (LV) subclinical systolic and diastolic dysfunction in childhood-onset systemic lupus erythematosus (c-SLE) patients using two-dimensional speckle-tracking (2DST) echocardiography. We also interrogated possible correlations between impairment of myocardial deformation and the SLE Disease Activity Index 2000 (SLEDAI-2K), as well as the presence of traditional and disease-related cardiovascular risk factors (CRFs). METHOD: A total of 50 asymptomatic patients and 50 controls (age 14.74 vs. 14.82 years, p = 0.83) were evaluated by standard and 2DST echocardiography. RESULTS: Despite a normal ejection fraction (EF), there was reduction in all parameters of LV longitudinal and radial deformation in patients compared to controls: peak longitudinal systolic strain (PLSS) [-20.3 (-11 to -26) vs. -22 (-17.8 to -30.4)%, p < 0.0001], PLSS rate [-1.19 ± 0.21 vs. -1.3 ± 0.25 s(-1), p = 0.0005], longitudinal strain rate in early diastole [1.7 (0.99-2.95) vs. 2 (1.08-3.00) s(-1), p = 0.0034], peak radial systolic strain [33.09 ± 8.6 vs. 44.36 ± 8.72%, p < 0.0001], peak radial systolic strain rate [1.98 ± 0.53 vs. 2.49 ± 0.68 s(-1), p < 0.0001], and radial strain rate in early diastole [-2.31 ± 0.88 vs. -2.75 ± 0.97 s(-1), p = 0.02]. Peak circumferential systolic strain [-23.67 ± 3.46 vs. -24.6 ± 2.86%, p = 0.43] and circumferential strain in early diastole [0.37 ± 0.17 vs. 0.41 ± 0.15, p = 0.27] were similar between patients and controls, although peak circumferential systolic strain rate [-1.5 ± 0.3 vs. -1.6 ± 0.3 s(-1), p = 0.036] was reduced in c-SLE. Further analysis of patients revealed a negative correlation between LV PLSS and SLEDAI-2K (r = -0.52, p < 0.0001), and also between LV PLSS and the number of CRFs per patient (r = -0.32, p = 0.024). CONCLUSIONS: 2DST echocardiography has identified subclinical LV deformation impairment in c-SLE patients. Disease activity and cumulative exposure to CRFs contribute to myocardial compromise.