Autoimmune endocrine disorders and coeliac disease in children and adolescents with juvenile idiopathic arthritis and rheumatic fever.

OBJECTIVES: There have been few studies on the association between childhood autoimmune and rheumatic diseases. Therefore, this study aims to assess the frequency of autoimmune thyroiditis (AT), coeliac disease (CD) and type 1 diabetes mellitus (T1DM) in children and adolescents with juvenile idiopathic arthritis (JIA) and rheumatic fever (RF). METHODS: This cross-sectional study includes 53 patients with JIA, 66 patients with RF and 40 healthy subjects controls. All subjects were evaluated for thyrotropin (TSH), triiodothyronine (T3), free thyroxine (FT4), antithyroglobulin (Tg) and antiperoxidase antibodies, fasting glucose, C-peptide, anti-glutamic acid decarboxylase (GAD), anti-islet cell (IA) and antitransglutaminase IgA (tTG) antibodies. Patients with thyroid dysfunction, positive anti-thyroid antibodies or tTG underwent thyroid ultrasonography and jejunal biopsy, respectively. RESULTS: In group 1 (n=53), 21 patients presented thyroid disorders (40%; 42% oligoarticular), either subclinical hypothyroidism (13%) or positive anti-thyroid antibodies (26%, 50% oligoarticular), significantly higher than in control group (p<0.009, OR=10.5, CI 1.29-85.2). In group 2 (n=66), thyroid disorders were identified in 11 patients, four (6%) with subclinical hypothyroidism and seven (11%) with positive anti-thyroid antibodies (p=0.06, compared with the control group). There were no cases of clinical overt hypothyroidism, positive anti-GAD or anti-IA, nor changes in serum C-peptide and glycemia. CD was confirmed in one patient from each group. CONCLUSIONS: Patients with JIA (especially the oligoarticular form) and RF should be investigated for thyroid dysfunction. Longitudinal studies could establish screening protocols for CD in patients with JIA and RF. The cost-effectiveness of T1DM screening is not justified in this population.

Disease presentation of 1312 childhood-onset systemic lupus erythematosus: influence of ethnicity.

OBJECTIVE: To evaluate the influence of ethnicity in presentation of childhood-onset systemic lupus erythematosus (cSLE) patients. METHODS: This multicenter study included cSLE patients (American College of Rheumatology criteria) followed in 27 Pediatric Rheumatology services of Brazil. Ethnicities were classified in four groups according to the parents' and all four grandparents' self-reported ethnicity. The statistical analysis was performed using the Bonferroni's correction (p < 0.0027). RESULTS: According to ethnic groups, 1537 cSLE patients were classified in Caucasian (n = 786), African-Latin American (n = 526), Asian (n = 8), and others/unknown (n = 217). Comparisons between 1312 African-Latin American and Caucasian revealed similar median age at cSLE diagnosis [12.2(2.6-18) vs. 12.1(0.3-18) years, p = 0.234], time interval to diagnosis [0.25(0-12) vs. 0.3(0-10) years, p = 0.034], and SLEDAI-2K score [14(0-55) vs. 14(0-63), p = 0.781] in both groups. The mean number of diagnostic criteria according to SLICC (6.47 ± 1.911 vs. 5.81 ± 1.631, p < 0.0001) and frequencies of maculopapular lupus rash (8% vs. 3%, p < 0.0001), palate oral ulcers (17% vs. 11%, p = 0.001), tongue oral ulcers (4% vs. 1%, p = 0.001), and nonscarring alopecia (29% vs. 16%, p < 0.0001) were significantly higher in African-Latin American, whereas malar rash (45% vs. 58%, p < 0.0001) was more frequent in Caucasian. The presence of anti-phospholipid antibody (23% vs. 12%, p < 0.0001), low complement levels (58% vs. 41%, p < 0.0001), and isolated direct Coombs test (10% vs. 5%, p = 0.001) was also significantly higher in the former group. CONCLUSIONS: Our study demonstrated that disease presentation severity of African-Latin American cSLE patients is comparable with Caucasian. Mucocutaneous manifestations and autoantibodies profile were the only distinctive features of the former group. The unique mixed background of Brazilian patients probably minimized race diversity spectrum of these patients. Key Points • Our study demonstrated that disease presentation severity of African-Latin American cSLE patients is comparable with Caucasian. • Mucocutaneous manifestations and autoantibodies profile were the only distinctive features of African-Latin American cSLE patients. • African-Latin American cSLE patients had more often anti-phospholipid antibodies and hypocomplementemia. • The unique mixed background of Brazilian patients probably minimized race diversity spectrum of these patients.