Abstract The etiology of juvenile idiopathic arthritis (JIA) is still unknown but genetic and enviromental factors play role in the pathogenesis. The aim of the study was to detect endoscopic and immunohistological changes in the gut in JIA compared with the controls and potential correlation of mucosal immunological activation with clinical activity of JIA. JIA patients (n=26) and negative controls (n=71) suffering from gastrointestinal symptoms without significant gastrointestinal disease were recruited for the study. Positive controls were patients with cows milk protein sensitive enteropathy (n=24). The intraepithelial lymphocytes counts, cytotoxic (granzyme A, B) and gamma/delta T-cell count and HLA-DR antigens were evaluated by using immunohistochemistry and messenger RNA expression levels of important immune mediators were assessed with real time PCR (RT-PCR) from fresh frozen intestinal mucosal samples. In JIA compared with negative controls, there was increased presence of lymphonodular hyperplasia and expression of HLA-DR antigens in abnormal mucosal cites, in crypts of the ileum. These changes were correlating with activity of JIA. In JIA compared with negative controls, there were found elevated granzyme B but decreased cytoprotective heat shock protein expression. The mRNA expression levels of anti- inflammatory mediators like TGFβ, IL10 and transcriptor factor of regulatory T-cells FOXP3, inversely correlated with activity of JIA. In conclusion, patients with JIA suffering from gastrointestinal symptoms display evidence of intestinal mucosal immune activation and there is an association between levels of mucosal immune alteration and clinical activity of JIA. These findings support the hypothesis that there is a link between the intestinal immune system and pathogenesis of juvenile idiopathic arthritis. In order to confirm these findings, more extensive series of JIA patients without gastrointestinal symptoms needs to be examined. / Tiivistelmä Lastenreuman tautimekanismi on tuntematon. Geneettiset ominaisuudet ja ympäristötekijät ovat yhteydessä taudin syntyyn. Tutkimuksen tavoitteena oli selvittää, onko suolen limakalvolla endoskooppisia tai immunohistologisia muutoksia enemmän lastenreumassa kuin kontrolleilla, ja että liittyvätkö muutokset niveltaudin aktiivisuuteen. Tutkimukseen otettiin 26 suolioireista lastenreumapotilasta, 76 verrokkia joilla ei ollut autoimmuunisairautta sekä 24 viivästynyttä maitoallergiaa sairastavaa lasta, joille tehtiin suolen tähystystutkimus. Ohutsuolinäytteistä arvioitiin immunohistologisesti solunsisäisten lymfosyyttien, gamma/delta-positiivisten lymfosyyttien sekä sytotoksisten (grantsyymi-A ja -B) lymfosyyttien määrä. Lisäksi määritettiin immunohistologisesti ohutsuolen limakalvon epiteelisolujen HLA-DR- antigeenien ja epiteelisolua suojaavien lämpöshokkiproteiinien ilmenemistä sekä käänteis-PCR-menetelmällä keskeisten välttäjäaineiden lähetti-RNA-tasoja. Tutkimuksessa lastenreumaa sairastavilla esiintyi enemmän suolen imukudoskertymää (lymfonodulaarinen hyperplasia) negatiiviseen verrokkiryhmään nähden sekä HLA-DR antigeenejä epätyypillisellä alueella ohutsuolen loppuosan limakalvon kryptassa. Nämä löydökset olivat yhteydessä lastenreuman aktiivisuuteen. Lastenreumassa oli verrokkeja enemmän sytotoksisia lymfosyyttejä ja vähemmän lämpöshokkiproteiineja. Tulehdusta suojaavat lähetti- RNA-tasot korreloivat käänteisesti lastenreumataudin aktiivisuuteen. Väitöstutkimuksen suolioireisilla lastenreumapotilailla oli suolen limakalvolla muutoksia, jotka sopivat poikkeavaan antigeenien käsittelyyn. Nämä löydökset tukevat hypoteesia, että lastenreumassa suolen limakalvon immunologinen aktivaatio on yhteydessä taudin puhkeamiseen. Jotta tulokset voisi yleistää, tarvittaisiin jatkotutkimus, joka on tehty suolioireettomilla lastenreumapotilailla ja riittävällä otoskoolla.

Introduction: The inflammation plays the essential role in the bone loss in juvenile idiopathic arthritis (JIA). Proinflammatory cytokines and also glucocorticoids (GCs) may activate bone resorption by osteoclasts. Simultaneously, bone formation can be attenuated, especially by inhibitors of proteins, which control the osteoblast differentiation. The aim was to verify the hypothesis that in patients with highly active JIA, reduction of bone formation via Wingless (Wnt) proteins inhibitors - Dickkopf 1 (Dkk-1) and sclerostin could be found. Except the densitometry measurements of bone and lean mass, we assessed markers of disease activity, bone metabolism and remodeling in young adult patients with JIA before and during 2 years of anti TNFα (tumour necrosis factor α) treatment, which decreases disease activity. Results: In patients with JIA before antiTNFα treatment, bone mineral density (BMD, g/cmš) was significantly reduced compared to controls. Values of BMD and body composition in JIA significantly depended on disease duration and GCs treatment. Serum concentration of sclerostin was significantly elevated in JIA compared to values in healthy controls. Values of the other monitored markers did not differ between JIA and controls. In patients with JIA, Dkk-1 correlated positively with C-reactive...

Introduction: Due to potentially severe sequelae (impaired growth, condylar resorption, and ankylosis) early diagnosis of chronic rheumatic arthritis of the temporomandibular joint (TMJ) and timely onset of therapy are essential. Aim: Owing to very limited evidence the aim of the study was to identify and discuss controversial topics in the guideline development to promote further focused research. Methods: Through a systematic literature search, 394 out of 3771 publications were included in a German interdisciplinary guideline draft. Two workgroups (1: oral and maxillofacial surgery, 2: interdisciplinary) voted on 77 recommendations/statements, in 2 independent anonymized and blinded consensus phases (Delphi process). Results: The voting results were relatively homogenous, except for a greater proportion of abstentions amongst the interdisciplinary group (p < 0.001). Eighty four percent of recommendations/statements were approved in the first round, 89% with strong consensus. Fourteen recommendations/statements (18.2%) required a prolonged consensus phase and further discussion. Discussion: Contrast-enhanced MRI was confirmed as the method of choice for the diagnosis of TMJ arthritis. Intraarticular corticosteroid injection is to be limited to therapy refractory cases and single injection only. In adults, alloplastic joint replacement is preferable to autologous replacement. In children/adolescents, autologous reconstruction may be performed lacking viable alternatives. Alloplastic options are currently still considered experimental.

Objectifs : L’objectif principal de cette étude était de décrire les caractéristiques des patients atteints d’arthrite juvénile idiopathique (AJI) qui ont fréquenté la nouvelle clinique dentaire spécialisée de l’articulation temporo-mandibulaire (ATM) développée au Centre hospitalier universitaire (CHU) Sainte-Justine. L’objectif secondaire visait à établir un portrait des ressources actuellement disponibles dans les hôpitaux pédiatriques canadiens pour les patients ayant un diagnostic d’AJI avec atteinte de l’ATM. Méthodes : Une collecte de données rétrospective des patients vus à la clinique spécialisée du CHU Sainte-Justine a été effectuée à partir des dossiers informatiques des patients. Les données comprenaient le sexe, l’âge, la spécialité du dentiste qui a vu le patient, le référent, le diagnostic, le type d’AJI, l’atteinte et la localisation à l’ATM, les symptômes, les plaintes signalées par le patient, le type d’imagerie utilisé, les traitements reçus et autres. Pour la deuxième partie de l’étude, des questionnaires ont été envoyés aux départements de rhumatologie et de médecine dentaire des 13 hôpitaux pédiatriques canadiens. Résultats : 86 patients atteints d’AJI de la clinique spécialisée ont été inclus, dont 42 % avaient une atteinte de l’ATM. L’imagerie panoramique était l’imagerie la plus prescrite chez les patients atteints d’AJI (91 %). Sept hôpitaux ont été inclus dans la deuxième partie de l’étude. Deux hôpitaux avaient une clinique spécialisée de l’ATM. Les réponses transmises entre les départements du même hôpital ne concordaient pas concernant les types d’imageries et de dentistes spécialistes accessibles. Conclusion : Les données des patients du CHU Sainte-Justine ne présentent pas d’écarts significatifs avec celles de la littérature. Les résultats des sondages montrent que peu d’hôpitaux pédiatriques canadiens disposent d’une clinique spécialisée de l’ATM pour l’AJI et que les rhumatologues ne semblent pas au fait de la prise en charge des patients atteints d’AJI par les différents dentistes spécialistes. / Objectives: The primary objective was to describe the characteristics of patients with juvenile idiopathic arthritis (JIA) in a newly developed specialized temporomandibular joint (TMJ) dental clinic at the Centre hospitalier universitaire (CHU) Sainte-Justine. The secondary objective aimed to describe a current portrait of the resources available in Canadian pediatric hospitals for JIA patients with TMJ involvement. Methods: A retrospective data collection of patients seen in the CHU Sainte-Justine specialized clinic was done from patient computer records. The data included sex, age, specialty of the dentist seen by the patient, referral source, diagnosis, JIA type, damage and location at the TMJ, symptoms, complaints reported by the patient, type of imaging used, treatments received and other. For the second part of the study, questionnaires were sent to the departments of rheumatology and dentistry of 13 Canadian pediatric hospitals. Results: A total of 86 JIA patients from the specialized clinic were included, of which 42% had TMJ involvement. The panoramic radiograph was the most prescribed imaging in patients with JIA (91%). A total of seven hospitals were included in the second part of the study. Two hospitals surveyed had a specialized TMJ clinic. Many results regarding the types of imaging and dental specialists accessible did not agree between the rheumatology and dentistry questionnaires within the same hospital. Conclusion: Most data from the CHU Sainte-Justine is consistent with findings in the literature. Results from surveys show that few Canadian pediatric hospitals have a specialized TMJ clinic for JIA and rheumatologists seem to lack understanding in the management of patients with JIA by different dental specialists.

Introduction: L’arthrite juvénile idiopathique (AJI) est la maladie rhumatologique la plus répandue chez les enfants. Lorsque l’articulation temporo-mandibulaire est touchée, le processus inflammatoire peut causer une perturbation de la croissance cranio-faciale et une destruction du condyle, ce qui peut engendrer des difformités dentofaciales et des malocclusions dentaires. Des facteurs environnementaux, tels que les médicaments et les habitudes parafonctionnelles, ont le potentiel d’influencer la progression de la maladie et, par conséquent, jouer un rôle dans l’étiologie des malocclusions des patients avec AJI. Objectifs : L’objectif principal est de comparer la fréquence et la sévérité des malocclusions des patients avec et sans AJI. L’objectif secondaire est d’investiguer la relation entre la sévérité des malocclusions des patients avec AJI et leurs médicaments et habitudes parafonctionnelles. Méthodes: L’échantillon était divisé en deux groupes: AJI (n=30) et contrôle (n=30). Un questionnaire médical, un examen orthodontique et un examen radiologique ont été complétés pour chaque patient. Résultats : Par rapport au groupe contrôle, les enfants avec AJI avaient plus d’asymétries dentofaciales (p=0.009), de classe II canines (p=0.05) et molaires (p<0.001), de surplombs vertical > 3.5 mm (p=0.011) et horizontal > 5.0 mm (p=0.033) augmentés, des courbes de Spee (p=0.044), de Wilson (p=0.044) et de Monson (p=0.003) accentuées, de chevauchement incisif mandibulaire (p=0.042) et de manque transverse maxillaire (p<0.001). Les médicaments et les habitudes parafonctionnelles n’avaient pas d’impact sur les malocclusions. Conclusion : Les enfants avec AJI avaient des malocclusions plus sévères. Un diagnostic précoce et des traitements médicaux et orthodontiques opportuns sont essentiels pour prévenir les dommages irréversibles causés par la maladie. / Introduction: Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease found in children. In cases affecting the temporomandibular joint (TMJ), the inflammatory process may cause disturbances in craniofacial growth and condylar destruction, both of which can lead to dentofacial deformities and dental malocclusions. Environmental factors such as medication and parafunctional habits have the potential to influence the disease progression and therefore play a role in the etiology of malocclusions of children with JIA. Objectives: The main objective of this study was to compare the frequency and the severity of malocclusions of patients with and without JIA. The secondary objective was to investigate the relationship between the severity of malocclusions of patients with JIA and their medication and parafunctional habits. Methods: The sample was divided into two groups: JIA (n=30) and control (n=30). A health questionnaire, an orthodontic examination, and radiographic records were completed for each patient. Results: Compared to the control group, children with JIA had more dentofacial asymmetry (p=0.009), Class II canine (p=0.05) and molar (p<0.001) relationships, increased overbite > 3.5 mm (p=0.011) and overjet > 5.0 mm (p=0.033), accentuated curves of Spee (p=0.044), Wilson (p=0.029) and Monson (p=0.003), lower incisor crowding (p=0.042) and maxillary transverse discrepancy (p<0.001). Medication and parafunctional habits did not influence malocclusions. Conclusion: Children with JIA have more severe malocclusions. An early diagnosis and timely medical and orthodontic treatment are crucial to prevent the irreversible damage caused by the disease.

Drug repositioning can save considerable time and resources and significantly speed up the drug development process. The increasing availability of drug action and disease-associated transcriptome data makes it an attractive source for repositioning studies. Here, we have developed a transcriptome-guided approach for drug/biologics repositioning based on multi-layer self-organizing maps (ml-SOM). It allows for analyzing multiple transcriptome datasets by segmenting them into layers of drug action- and disease-associated transcriptome data. A comparison of expression changes in clusters of functionally related genes across the layers identifies “drug target” spots in disease layers and evaluates the repositioning possibility of a drug. The repositioning potential for two approved biologics drugs (infliximab and brodalumab) confirmed the drugs’ action for approved diseases (ulcerative colitis and Crohn’s disease for infliximab and psoriasis for brodalumab). We showed the potential efficacy of infliximab for the treatment of sarcoidosis, but not chronic obstructive pulmonary disease (COPD). Brodalumab failed to affect dysregulated functional gene clusters in Crohn’s disease (CD) and systemic juvenile idiopathic arthritis (SJIA), clearly indicating that it may not be effective in the treatment of these diseases. In conclusion, ml-SOM offers a novel approach for transcriptome-guided drug repositioning that could be particularly useful for biologics drugs.

For most children, occult vascular damage is minimal and has a slow rate of progression likely due to the existence of healthy lifestyles and the prevalence of preventative behaviours. However, there is evidence to suggest a marked increase in the prevalence of traditional and emerging cardiovascular risk factors in children with chronic inflammatory conditions due to the common aetiology pathways of inflammation and atherosclerosis. In the current cross-sectional study, a comprehensive vascular assessment was conducted on 21 children with various chronic inflammatory conditions including juvenile idiopathic arthritis (JIA), cystic fibrosis (CF), type I diabetes mellitus (T1DM) and inflammatory bowel disease (IBD) (CIC, 12.7 ± 2.3 years) compared to 9 healthy, age and sex- matched controls (CON, 13.1 ± 1.8 years). B-mode ultrasound images were used to assess carotid artery intima media thickness (cIMT) as well as local arterial stiffness through measurement of compliance and distensibility with the use of concurrent applanation tonometry. Whole-body arterial stiffness was measured by assessing pulse wave velocity (PWV) between the carotid and dorsalis pedis arteries. A brachial flow mediated dilation (FMD) test was implemented to assess endothelial function of the brachial artery. Twelve hour-fasted blood samples were collected and analyzed for blood lipids and an acute inflammatory marker, C-reactive protein (CRP). There were no group differences in cIMT (p=0.18), distensibility (p=0.40), compliance (p=0.88), whole body PWV (p=0.74) or LDL- cholesterol (p=0.99). The CIC group demonstrated significantly lower FMD when iii compared to CON (p=0.01). There were no group differences in inflammatory levels, as indicated by concentration of CRP (p=0.63). Sub-analyses revealed similar cIMT, distensibility, compliance, PWV and LDL levels between children with JIA (n=11, 12.6 ± 2.9 years), CON (n=9, 13.1 ± 1.8 years) and the other inflammatory conditions (INFL, n=10, 12.4 ± 1.7 years). Both JIA and INFL reported lower FMD when compared to CON (p=0.04). INFL had lower BMI compared to JIA and CON (p=0.02). The primary findings from this study suggest that arterial structure is similar between children with a CIC and their healthy peers; however, arterial function, as indicated by FMD (%), was reduced in the CIC group. This finding is essential in that it helps to identify an area for targeted intervention and/or prevention of future CV events as endothelial dysfunction is known to be an early event in the pathophysiology of atherosclerosis. / Thesis / Master of Science (MSc)

L'arthrite juvénile idiopathique (AJI) est une maladie chronique infantile d'origine inconnue caractérisée par de la douleur chronique, des enflures articulaires et de la fatigue. Malgré les effets positifs de l'activité physique (AP) sur les symptômes reliés à l’arthrite et la santé générale, les jeunes atteints d'AJI adoptent souvent un mode de vie sédentaire. Par conséquent, ils sont plus à risque de développer d’autres maladies chroniques telles les maladies cardio-vasculaires. Cela nécessite l’accès à un programme efficace pour inciter ces personnes à faire de l'AP. En réponse à ceci, notre équipe a développé le programme ActiJI livré sur Instagram promouvant l’engagement à l’AP auprès des jeunes personnes vivant avec l’AJI. La présente étude évalue l’utilisabilité d’ActiJI en ciblant la satisfaction et la performance d’utilisation parmi les jeunes atteints d'AJI. Une étude qualitative descriptive a été utilisée. Des adolescents (âgés de 13 à 17 ans) et des jeunes adultes (âgés de 18 à 25 ans) atteints d'AJI ont été recrutés via des associations patients, des centres hospitaliers et de réadaptation. Au total, 28 participants (âge moyen = 18,69 ans) ont complété des entretiens semi-dirigés sur deux cycles itératifs via Zoom (Enterprise Version 5.0.2). Les verbatims ont été transcrits, puis triés, organisés et codés avec MAXQDA 11 selon les recommandations de Huberman et al.. Le processus de codage s'est appuyé sur six thèmes ancrés dans les principes théoriques de l’utilisabilité et définis par les équipes de recherche, ceux-ci comprenaient la confidentialité et la sécurité, l'esthétique du design, les fonctionnalités, l'organisation, la connexion sociale et le contenu de la page. Nos résultats démontrent que le programme ActiJI est vu comme étant sécuritaire, convivial, et est apprécié pour ses activités de groupe et les interactions entre pairs. En particulier, le soutien éventuel offert par les professionnels de santé et les pairs motiveraient les jeunes atteints d'AJI à s'engager davantage dans l'AP. Les participants rapportent que le programme ActiJI est facilement utilisable, et que la page Instagram peut être naviguée efficacement. Les recommandations des participants ont été intégrées au programme ActiJI. Une prochaine étude visera à évaluer la faisabilité d’ActiJI. / Juvenile idiopathic arthritis (JIA) is the most common childhood chronic rheumatic condition of unknown origin and is characterized by chronic pain, joint inflammation and fatigue. Despite the benefits of physical activity (PA) in mitigating arthritis symptoms and for general health, young people with JIA have a greater tendency to adopt a sedentary lifestyle rather than engage in PA. Consequently, these young people are at greater risk for other chronic health conditions such as cardiovascular disease. Access to innovative and attractive means of promoting PA among these young people is sorely needed. In response to this need, our team developed JIActiv an Instagrambased program promoting physical activity among young people living with JIA. The current study aimed to assess the usability of the JIActiv program in terms of user performance and the level of satisfaction among adolescents and young adults living with JIA. We used a descriptive qualitative study design. Adolescents (ages 13 to 17 years) and young adults (aged 18 to 25 years) living with JIA were recruited from rheumatology clinics in rehabilitation and hospital centers, as well as through patient organizations. A total of 28 young people (mean age = 18.69, SD=± 2.28 years) completed semi-structured interviews over two iterative cycles using Zoom (Enterprise Version 5.0.2). The audio recordings of the interviews were transcribed word by word, then sorted, organized, and coded using MAXQDA 11 software following recommendations by Huberman et al.. The coding process was based on six themes anchored within the theoretical principals of usability testing and were specified by the research teams, which included privacy and safety, design aesthetics, functionalities, organization, social connection, and content of the page . Our findings have shown that the JIActiv program is viewed as secure and user-friendly. Participants appreciated the group activities and peer interactions. Notably, the potential support offered by healthcare professionals and peers may motivate those living with JIA to engage more in PA. Study participants reported that the JIActiv program was easy to use, and they navigated the Instagram page effectively. Participant recommendations were integrated within the JIActiv program. A subsequent study will assess the feasibility of JIActiv.

L'obtention des données a été subventionnée par CIORA (Canadian Initiative for Outcomes in Rheumatology Care). CIORA a aussi financé l'analyse des données effectuées par Justine Zehr. L'Initiative Canadienne Pour Des Resultats En Soins Rhumatologiques (ICORA) a financé l'obtention des données et une partie de l'analyse statistique présentée dans ce mémoire. / La plupart des femmes ayant été atteintes d’arthrite juvénile idiopathique (AJI) continuent de souffrir d’arthrite à l’âge adulte. Certains des médicaments utilisés dans le traitement de l’arthrite tels que les corticostéroïdes et les antiinflammatoires non stéroïdiens (AINS) ne sont pas recommandés durant la grossesse. Le but de ce mémoire est d’estimer l’impact de la prise de ces médicaments sur les événements néfastes à l’accouchement chez ces femmes et leur bébé. Des données administratives sur les prescriptions de médicaments et les hospitalisations d’une cohorte de 1756 femmes ayant souffert d’AJI sont utilisées. Elles ont permis de reconstruire l’historique de consommation de médicaments contre l’arthrite chez les femmes durant la grossesse et l’année précédente. Pour ce faire, deux sous-cohortes de femmes ayant souffert d’AJI ont été formées : une pour la période grossesse et une autre pour la grossesse et l’année précédant celle-ci. Les événements d’intérêt étaient : malformations congénitales, complications néonatales, complications maternelles et petit poids pour l’âge gestationnel. Les proportions de cas présentant l’un de ces événements variaient entre 11,52% et 37,08%. Les médicaments ont été modélisés en terme d’utilisation ou de durée totale de consommation durant la période d’étude. Pour chaque événement, des modèles logistiques ont été estimés pour mesurer l’association entre la prise de médicaments et l’événement, en ajustant pour des variables de confusion potentielles : hypertension avant la grossesse, âge à l’accouchement et obtention du diplôme de secondaire. La consommation de corticostéroïdes semble augmenter statistiquement significativement le risque de présenter des malformations congénitales mais n’avoir aucun impact sur les autres événements. Aucun lien statistiquement significatif n’a été observé entre la consommation de AINS et les événements d’intérêt. / Most women diagnosed with juvenile idiopathic arthritis (JIA) continue to suffer from arthritis in adulthood. Some of the drugs used to treat arthritis such as corticosteroids and non-steroidal anti-inflammatory drugs (NSAIDs) are not recommended during pregnancy. The objective of this thesis is to estimate the impact of these drugs on adverse birth outcomes in women previously diagnosed with JIA and their baby. Administrative data on drug prescriptions and hospitalizations in a cohort of 1756 women with a history of JIA were used to determine individual histories of drug use for the treatment of arthritis during pregnancy and during the year leading to the pregnancy. Two sub-cohorts of women who suffered from JIA were created : one corresponding to the pregnancy and the other to the pregnancy and the year leading to the pregnancy. The events of interest were : congenital anomalies, neonatal adverse outcomes, maternal adverse outcomes and small for gestational age babies. Proportions of the events ranged between 11,52% and 37,08%. Drugs were modelled in terms of use or duration of use during each of the study periods. Logistic regression models were fitted to measure the association between drugs and each of the events, adjusting for the following potential confounding variables : hypertension before pregnancy, maternal age and graduating from high school. The consumption of corticosteroids was associated with a statistically significant increased risk of congenital anomalies but had no impact on the other adverse events. No statistically significant associations were observed between consumption of NSAIDs and the adverse events of interest.

v anglickém jazyce Introduction: No information was known about frequency of common inflammatory disorders in rheumatology in the Czech Republic. Aims of the study: To estimate the standardized annual incidence (INC) and point prevalence (PREV) of six diseases (rheumatoid arthritis-RA, juvenile idiopathic arthritis-JIA, gout, psoriatic arthritis-PsA, ankylosing spondylitis-AS, reactive arthritis-ReA) in a population-based study in two regions of the Czech Republic (CR). Methods: INC: Incident cases were registered on condition that the definite diagnosis was confirmed according to existing classification criteria during the study period. PREV was studied on the basis of identification of established diagnoses at a time point. Crude rates were standardized for age and sex. Results: Both INC and PREV are shown per 100.000 inhabitants. RA INC:31 (95%CI 20-42), PREV:610 (95%CI 561-658). Gout-INC:41 (95%CI 28-53), PREV:300 (95% CI 266-334). JIA-INC: 13 (95% CI 1-20), PREV:140 (95%CI 117-280). PsA-INC:3,6 (95% CI 1-8), PREV:49 (95%CI 40-60). AS-INC:6 (95% CI 3-11), PREV:94 (95% CI 94-109). ReA-INC:9 (95% CI 6-15), PREV:91 (95% CI 78-106). Conclusion: This is the first population-based study estimating annual incidence and prevalence rates of the most common rheumatological disorders in the Czech...