Search

We are indebted to the patients and healthy controls for their essential collaboration to this study. We also thank the National DNA Bank Repository (Salamanca) for supplying part of the control samples. This study was supported by European Union FEDER funds and `Fondo de Investigaciones Sanitarias (Grant PI18/00042) from 'Instituto de Salud Carlos III' (ISCIII, Health Ministry, Spain). DP-P is a recipient of a Rio Hortega programme fellowship from the ISCIII, co-funded by the European Social Fund (ESF, `Investing in your future) (Grant Number CM20/00006). SR-M is supported by funds of the RETICS Program (RD16/0012/0009) (ISCIII, co-funded by the European Regional Development Fund (ERDF)). VP-C is supported by a pre-doctoral grant from IDIVAL (PREVAL 18/01). BA-M is a recipient of a `Lopez Albo Post-Residency Programme funded by Servicio Cantabro de Salud. LL-G is supported by funds from IDIVAL (INNVAL20/06). OG is staff personnel of Xunta de Galicia (Servizo Galego de Saude (SERGAS)) through a research-staff stabilization contract (ISCIII/SERGAS) and his work is funded by ISCIII and the European Union FEDER fund (Grant Numbers RD16/0012/0014 (RIER) and PI17/00409). He is beneficiary of project funds from the Research Executive Agency (REA) of the European Union in the framework of MSCA-RISE Action of the H2020 Programme, project 734899-Olive-Net. RL-M is a recipient of a Miguel Servet type I programme fellowship from the ISCIII, co-funded by ESF (`Investing in your future) (Grant Number CP16/00033)., Cytokines signalling pathway genes are crucial factors of the genetic network underlying the pathogenesis of Immunoglobulin-A vasculitis (IgAV), an inflammatory vascular condition. An influence of the interleukin (IL)33- IL1 receptor like (IL1RL)1 signalling pathway on the increased risk of several immune-mediated diseases has been described. Accordingly, we assessed whether the IL33-IL1RL1 pathway represents a novel genetic risk factor for IgAV. Three tag polymorphisms within IL33 (rs3939286, rs7025417 and rs7044343) and three within IL1RL1 (rs2310173, rs13015714 and rs2058660), that also were previously associated with several inflammatory diseases, were genotyped in 380 Caucasian IgAV patients and 845 matched healthy controls. No genotypes or alleles differences were observed between IgAV patients and controls when IL33 and IL1RL1 variants were analysed independently. Likewise, no statistically significant differences were found in IL33 or IL1RL1 genotype and allele frequencies when IgAV patients were stratified according to the age at disease onset or to the presence/absence of gastrointestinal (GI) or renal manifestations. Similar results were disclosed when IL33 and IL1RL1 haplotypes were compared between IgAV patients and controls and between, European Commission, 'Instituto de Salud Carlos III' (ISCIII, Health Ministry, Spain) PI18/00042 Instituto de Salud Carlos III, European Social Fund (ESF) CM20/00006, RETICS Program (ISCIII) RD16/0012/0009, European Commission IDIVAL 18/01 INNVAL20/06, Servicio Cantabro de Salud, European Union FEDER fund RD16/0012/0014 PI17/00409, European Commission 734899 CP16/00033

We are indebted to the patients and healthy controls for their essential collaboration to this study. We also thank the National DNA Bank Repository (Salamanca) for supplying part of the control samples. This study was supported by European Union FEDER funds and `Fondo de Investigaciones Sanitarias´ (grant PI18/00042) from ‘Instituto de Salud Carlos III’ (ISCIII, Health Ministry, Spain). DP-P is a recipient of a Río Hortega programme fellowship from the ISCIII, co-funded by the European Social Fund (ESF, `Investing in your future´) (grant number CM20/00006). SR-M is supported by funds of the RETICS Program (RD16/0012/0009) (ISCIII, co-funded by the European Regional Development Fund (ERDF)). VP-C is supported by a pre-doctoral grant from IDIVAL (PREVAL 18/01). BA-M is a recipient of a `López Albo´ Post-Residency Programme funded by Servicio Cántabro de Salud. LL-G is supported by funds from IDIVAL (INNVAL20/06). OG is staff personnel of Xunta de Galicia (Servizo Galego de Saude (SERGAS)) through a research-staff stabilization contract (ISCIII/SERGAS) and his work is funded by ISCIII and the European Union FEDER fund (grant numbers RD16/0012/0014 (RIER) and PI17/00409). He is beneficiary of project funds from the Research Executive Agency (REA) of the European Union in the framework of MSCA-RISE Action of the H2020 Programme, project 734899—Olive-Net. RL-M is a recipient of a Miguel Servet type I programme fellowship from the ISCIII, co-funded by ESF (`Investing in your future´) (grant number CP16/00033)., Supplementary Information The online version contains supplementary material available at https:// doi. org/ 10. 1038/ s41598- 021- 91055-z, BAFF, APRIL and BAFF-R are key proteins involved in the development of B-lymphocytes and autoimmunity. Additionally, BAFF, APRIL and BAFFR polymorphisms were associated with immunemediated conditions, being BAFF GCTGT>A a shared insertion-deletion genetic variant for several autoimmune diseases. Accordingly, we assessed whether BAFF, APRIL and BAFFR represent novel genetic risk factors for Immunoglobulin-A vasculitis (IgAV), a predominantly B-lymphocyte inflammatory condition. BAFF rs374039502, which colocalizes with BAFF GCTGT>A, and two tag variants within APRIL (rs11552708 and rs6608) and BAFFR (rs7290134 and rs77874543) were genotyped in 386 Caucasian IgAV patients and 806 matched healthy controls. No genotypes or alleles differences were observed between IgAV patients and controls when BAFF, APRIL and BAFFR variants were analysed independently. Likewise, no statistically significant differences were found in the genotype and allele frequencies of BAFF, APRIL or BAFFR when IgAV patients were stratified according to the age at disease onset or to the presence/absence of gastrointestinal (GI) or renal manifestations. Similar results were disclosed when APRIL and BAFFR haplotypes were compared between IgAV patients and controls and between IgAV patients stratified according to the clinical characteristics mentioned above. Our results suggest that BAFF, APRIL and BAFFR do not contribute to the genetic network underlying IgAV., European Union FEDER fund RD16/0012/0014, H2020 Programme 734899, Health Ministry, Servicio Cántabro de Salud, Servizo Galego de Saude, European Commission PI18/00042 EC, Research Executive Agency REA, Instituto de Salud Carlos III CP16/00033,PI17/00409 ISCIII, European Social Fund CM20/00006,RD16/0012/0009 ESF, European Regional Development Fund ERDF, Instituto de Investigación Marqués de Valdecilla PREVAL 18/01 IDIVAL, Servicio Gallego de Salud SERGAS

Resumen El acronimo sindrome SAPHO (sinovitis, acne, pustulosis, hiperostosis y osteitis) engloba tanto manifestaciones cutaneas como muculoesqueleticas, entre ellas hiperostosis de los huesos y de las articulaciones de la pared toracica anterior, asociado a manifestaciones cutaneas; acne fulminans e hidradenitis supurativa. Los criterios diagnosticos no han sido validados en ninos. El tratamiento inicial con antiinflamatorios no esteroideos en ocasiones es insuficiente y puede ser preciso asociar corticoides, farmacos modificadores de la enfermedad, antagonistas del factor de necrosis tumoral o bifosfonatos. Presentamos el caso clinico de un escolar con afectacion poliarticular, osteoartritis de articulacion esternoclavicular con importante componente inflamatorio y acne conglobata, con buena respuesta al tratamiento con pamidronato por via intravenosa.

Background Osteoporosis incidence in children is increasing due to the increased survival rate of patients suffering from chronic diseases and the increased use of drugs that can damage bones. Recent changes made to the definition of childhood osteoporosis, along with the lack of guidelines or national consensuses regarding its diagnosis and treatment, have resulted in a wide variability in the approaches used to treat this disease. For these reasons, the Osteogenesis Imperfecta and Childhood Osteoporosis Working Group of the Spanish Society of Pediatric Rheumatology has sounded the need for developing guidelines to standardize clinical practice with regard to this pathology. Methods An expert panel comprised of 6 pediatricians and 5 rheumatologists carried out a qualitative literature review and provided recommendations based on evidence, when that was available, or on their own experience. The level of evidence was determined for each section using the Oxford Centre for Evidence-based Medicine (CEBM) system. A Delphi survey was conducted for those recommendations with an evidence level of IV or V. This survey was sent to all members of the SERPE. All recommendations that had a level of agreement higher or equal to 70% were included. Results Fifty-one recommendations, categorized into eight sections, were obtained. Twenty-four of them presented an evidence level 4 or 5, and therefore a Delphi survey was conducted. This was submitted electronically and received a response rate of 40%. All recommendations submitted to the Delphi round obtained a level of agreement of 70% or higher and were therefore accepted. Conclusion In summary, we present herein guidelines for the prevention, diagnosis and treatment of secondary childhood osteoporosis based on the available evidence and expert clinical experience. We believe it can serve as a useful tool that will contribute to the standardization of clinical practice for this pathology. Prophylactic measures, early diagnosis and a proper therapeutic approach are essential to improving bone health, not only in children and adolescents, but also in the adults they will become in the future., This workshop was organized by the Osteogenesis Imperfecta and secondary osteoporosis working group form SERPE. Financial support was provided by a Spanish Pediatric Rheumtology Society scholarship for Pediatric Rheumatology research and Laboratorios Rubio and Alexion Pharma grant.

Objective IgA vasculitis (Henoch-Schonlein) (IgAV), formerly called Henoch-Schonlein purpura, is the most common vasculitis in children, but it is not rare in adults. Increased familial occurrence supports a genetic predisposition to IgAV. In this context, an association with the HLA–DRB1*01 phenotype has been suggested in Caucasian individuals with IgAV. However, data on the potential association of IgAV with HLA–DRB1*01 were based on small case series. We undertook this study to further investigate this potential association by performing HLA–DRB1 genotyping in the largest series of IgAV patients ever assessed for genetic studies in Caucasians. Methods We assessed 342 Spanish patients with IgAV as well as 303 controls matched for sex and ethnicity. IgAV patients were required to fulfill the classification criteria described by Michel et al as well as the American College of Rheumatology 1990 classification criteria. HLA–DRB1 alleles were determined using the polymerase chain reaction–sequence-specific oligonucleotide probe method. Results We found a statistically significant increase in the frequency of the HLA–DRB1*01 phenotype in IgAV patients compared with controls (43% versus 27%; P < 0.001) (odds ratio 2.03 [95% confidence interval 1.43–2.87]). This was due to the increased frequency of the HLA–DRB1*0103 allele in IgAV patients compared with controls (14.3% versus 2.0%; P < 0.001) (odds ratio 8.27 [95% confidence interval 3.46–23.9]). These results remained statistically significant after Bonferroni adjustment. In contrast, a statistically significant decrease in the frequency of the HLA–DRB1*03 phenotype, due to the presence of the HLA–DRB1*0301 allele, was observed in IgAV patients compared with controls (5.6% versus 18.2%; P < 0.001) (odds ratio 0.26 [95% confidence interval 0.14–0.47]), even after Bonferroni adjustment. No association of HLA–DRB1 with specific features of the disease was found. Conclusion Our study confirms an association of IgAV with HLA–DRB1*01 in Caucasians. There also appears to be a protective effect against the development of IgAV in Caucasians carrying the HLA–DRB1*03 phenotype.

The genetic component of Immunoglobulin-A (IgA) vasculitis is still far to be elucidated. To increase the current knowledge on the genetic component of this vasculitis we performed the first genome-wide association study (GWAS) on this condition. 308 IgA vasculitis patients and 1,018 healthy controls from Spain were genotyped by Illumina HumanCore BeadChips. Imputation of GWAS data was performed using the 1000 Genomes Project Phase III dataset as reference panel. After quality control filters and GWAS imputation, 285 patients and 1,006 controls remained in the datasets and were included in further analysis. Additionally, the human leukocyte antigen (HLA) region was comprehensively studied by imputing classical alleles and polymorphic amino acid positions. A linkage disequilibrium block of polymorphisms located in the HLA class II region surpassed the genome-wide level of significance (OR = 0.56, 95% CI = 0.46–0.68). Although no polymorphic amino acid positions were associated at the genome-wide level of significance, P-values of potential relevance were observed for the positions 13 and 11 of HLA-DRB1 (P = 6.67E-05, P = 1.88E-05, respectively). Outside the HLA, potential associations were detected, but none of them were close to the statistical significance. In conclusion, our study suggests that IgA vasculitis is an archetypal HLA class II disease., This study was supported by European Union FEDER funds and “Fondo de Investigaciones Sanitarias” (grant PI12/00193) from ‘Instituto de Salud Carlos III’ (ISCIII, Health Ministry, Spain). RL-M was supported by the Miguel Servet I programme of the Spanish Ministry of Economy and Competitiveness through the grant CP16/00033. FDC was supported by the Ramón y Cajal programme of the Spanish Ministry of Economy and Competitiveness through the grant RYC-2014-16458. FG was recipient of a Sara Borrell postdoctoral fellowship from the “Instituto Carlos III de Salud” at the Spanish Ministry of Health (Spain) (CD15/00095). SR-M and BU were supported by funds from the RETICS Program (RIER) (RD16/0012/0009 and RD12/0009/0013, respectively).

The acronym of SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis and osteitis) combines a cluster of cutaneous and musculoskeletal manifestations, such as hyperostosis of bones of the anterior chest wall associated with acne fulminans and hidradenitis suppurativa. There are no validated diagnostic criteria in children. Nonsteroidal anti-inflammatory drugs are not always sufficient, and the use of corticosteroids, disease-modifying agents, tumor necrosis factor-α inhibitors or bisphosphonates may be necessary. We present the case of a child with polyarticular involvement, osteoarthritis of the sternoclavicular joint with severe inflammatory disorders and acne conglobata, with an excellent response to intravenous pamidronate.

[Introduction] To determine whether the PTPN22 (protein tyrosine phosphatase nonreceptor 22)/CSK (c-src tyrosine kinase) pathway is implicated in the susceptibility and clinical heterogeneity of Henoch-Schönlein purpura (HSP) in the largest series of Caucasian HSP patients ever assessed for genetic studies., [Methods] A set of 329 Spanish patients diagnosed with HSP fulfilling the American College of Rheumatology and the Michel et al. classification criteria and 515 sex and ethnically matched controls were recruited in this study. Two well-known CSK (CSK rs34933034 and CSK rs1378942) and two functional PTPN22 (PTPN22 rs2476601 (R620W) and PTPN22 rs33996649 (R263Q)) polymorphisms, previously associated with autoimmunity, were genotyped with TaqMan single nucleotide polymorphism (SNP) genotyping assays., [Results] No significant differences in the genotype and allele frequencies between HSP patients and controls were observed when the CSK rs34933034, CSK rs1378942, PTPN22 rs2476601 (R620W) and PTPN22 rs33996649 (R263Q) polymorphisms were analyzed independently. In keeping with this observation, no significant differences were found when we assessed these polymorphisms combined conforming haplotypes. In addition, there were no differences in the allele or genotype frequencies when HSP patients were stratified according the age at disease onset, sex, presence of arthralgia/arthritis, nephritis or gastrointestinal manifestations., [Conclusions] Our results do not support association between PTPN22/CSK and HSP., This study was supported by a grant from “Fondo de Investigaciones Sanitarias” PI12/00193 (Spain). RLM is a recipient of a Sara Borrell postdoctoral fellowship from the Instituto de Salud Carlos III at the Spanish Ministry of Health (Spain) (CD12/00425). FG and BU are supported by funds from the RETICS Program (RIER) (RD12/0009/0013).

López-Mejías, Raquel et al., [Introduction] A study was conducted to determine whether the human leukocyte antigen (HLA) B alleles are implicated in the susceptibility to Henoch-Schönlein purpura (HSP) in the largest series of Caucasian HSP patients ever assessed for genetic studies., [Methods] The study population was composed of 349 Spanish patients diagnosed with HSP fulfilling the American College of Rheumatology and the Michel et al. classification criteria, and 335 sex and ethnically matched controls. HLA-B phenotypes were determined by sequencing-based typing (SBT) and analyzed by chi-square or Fisher exact test., [Results] A statistically significant increase of HLA-B*41:02 allele in HSP patients when compared with controls was found (8.3% versus 1.5% respectively; P = 0.0001; OR (odds ratio) =5.76 [2.15-19.3]). These results remained statistically significant after adjusting for Bonferroni correction (P = 0.0028). An internal validation also confirmed the susceptibility effect on HSP associated with HLA-B*41:02 (OR = 5.70 [1.98-16.44]). Since a former study described an association between HLA-DRB1*01:03 and HSP susceptibility, we also evaluated the implication of HLA-B*41:02 independently of HLA-DRB1*01:03. Interestingly, the association remained statistically significant (P = 0.0004, OR = 4.97 [1.8-16.9]). No HLA-B association with specific HSP clinical features was found., [Conclusions] Our study indicates that HLA-B*41:02 is associated with the susceptibility to HSP in Spanish patients irrespective of HLA-DRB1 status., This study was supported by a grant from ‘Fondo de Investigaciones Sanitarias’ PI12/00193 (Spain). RLM is a recipient of a Sara Borrell postdoctoral fellowship from the Instituto de Salud Carlos III at the Spanish Ministry of Health (Spain) (CD12/00425). FG and BU are supported by funds from the RETICS Program (RIER) (RD12/0009/0013).

Objective: Henoch-Schönlein purpura (HSP) is the most common vasculitis in children but it is not exceptional in adults. Increased familial occurrence supports a genetic predisposition for HSP. In this context, an association with the human leukocyte antigen-HLA-DRB1*01 phenotype has been suggested in Caucasian individuals with HSP. However, data on the potential association of HSP with HLA-DRB1*01 were based on small case series. To further investigate this issue, we performed HLA-DRB1 genotyping of the largest series of HSP patients ever assessed for genetic studies in Caucasians. Methods: 342 Spanish patients diagnosed with HSP fulfilling the American College of Rheumatology and the Michel et al classification criteria, and 303 sex and ethnically matched controls were assessed. HLA-DRB1 alleles were determined using a PCR-Sequence-Specific-Oligonucleotide Probe (PCR-SSOP) method. Results: A statistically significant increase of HLA-DRB1*01 in HSP patients when compared with controls was found (43% vs 7%, respectively; p0.001; odds ratio-OR=2.03 [1.43-2.87]). It was due to the increased frequency of HLA-DRB1*0103 phenotype in HSP (14% vs 2%; p0.001; OR=8.27 [3.46-23.9]). These results remained statistically significant after adjusting for Bonferroni correction. In contrast, a statistically significant decreased frequency of the HLA-DRB1*0301 phenotype was observed in patients compared to controls (5.6% vs 18.1%, respectively; p0.001, OR=0.26 [0.14-0.47]), even after adjustment for Bonferroni correction. No HLA-DRB1 association with specific features of the disease was found. Conclusion: Our study confirms an association of HSP with HLA-DRB1*01 in Caucasians. Also, a protective effect against the development of HSP appears to exist in Caucasians carrying the HLA-DRB1*03 phenotype. This article is protected by copyright. All rights reserved.