EULAR/PRINTO/PRES criteria for Henoch-Schönlein purpura, childhood polyarteritis nodosa, childhood Wegener granulomatosis and childhood Takayasu arteritis: Ankara 2008. Part II: Final classification criteria.

OBJECTIVES: To validate the previously proposed classification criteria for Henoch-Schönlein purpura (HSP), childhood polyarteritis nodosa (c-PAN), c-Wegener granulomatosis (c-WG) and c-Takayasu arteritis (c-TA). METHODS: Step 1: retrospective/prospective web-data collection for children with HSP, c-PAN, c-WG and c-TA with age at diagnosis

Different KIRs confer susceptibility and protection to adults with latent autoimmune diabetes in Latvian and Asian Indian populations.

KIRs (killer Ig-like receptors) expressed on natural killer (NK) cells are an important component of innate (and adaptive) immunity. They are either activatory or inhibitory, and certain KIRs are known to interact with specific motifs of HLA Class I molecules, which is very crucial in determining whether a cell is targeted to lysis or otherwise. Latent autoimmune diabetes in adults (LADA) is a slowly progressive form of autoimmune diabetes, with an adult onset (>30 years). Because autoantibodies and autoimmunity involved are involved in the etiology of LADA, KIRs might play an important role in conferring susceptibility to or protection against the disease. The purpose of this study was to identify killer immunoglobulin-like receptor (KIR) genes, which are associated with susceptibility to and protection against type 1 diabetes in Latvian and Asian Indian patients with LADA. KIR and HLA-C ligand genotyping was performed using PCR-SSP in LADA patients from Latvia (n= 45) with age- and sex-matched controls (n= 92) and from India (n= 86) with controls (n= 98). Results showed that in Latvian patients with LADA, KIRs 2DL1, 2DS2, and 2DS4 were associated with susceptibility and KIR 2DS5 with protection. In Asian Indian LADA patients, KIRs 2DL5 and 3DL1 were associated with susceptibility and KIRs 2DS1 and 2DS3 with protection. Stratification analyses for KIRs that bind to HLA-C1 and C2 were performed. We concluded that KIRs are important in conferring susceptibility (or protection) to adult patients with LADA in both our study populations. However the KIR genes (and their HLA-C ligands) conferring susceptibility or protection in these two populations differ, showing a role of ethnicity in disease susceptibility.

Helicobacter pylori infection among children with gastrointestinal symptoms: a high prevalence of infection among patients with reflux oesophagitis.

AIM: To investigate the link between H.pylori infection and dyspepsia in children, and association with reflux oesophagitis. PATIENTS AND METHODS: H.pylori status was detected by rapid urease test and/or culture in 130 consecutive symptomatic children coming for upper gastrointestinal endoscopy: 40 - aged 8-12 years (55% boys); 90 - aged 13-18 years (21% boys). Endoscopic findings were analyzed. H.pylori prevalence in the age group 8-12 years was compared to the prevalence among 55 asymptomatic children, aged 7-12 years (13C-urea breath test). STATISTICAL ANALYSIS: chi(2) test, Fisher's test, and logistic regression analysis. RESULTS: The prevalence of H.pylori infection among patients with gastrointestinal symptoms was 54%. It was significantly higher among patients with reflux oesophagitis compared to patients with hyperaemic gastropathy: OR = 5.5; p = 0.03, 95% CI: 1.15-26.3. In logistic regression analysis, no significant difference between the prevalence of H.pylori infection between asymptomatic and symptomatic children could be demonstrated (OR = 1.8; 95% CI: 0.62-5.14). CONCLUSIONS: The prevalence of H.pylori was significantly higher among patients with reflux oesophagitis compared to patients with hyperaemic gastropathy alone. Adjusting for age the prevalence of H.pylori infection was not higher among symptomatic children compared to asymptomatic children of the same age.

Association of SUMO4 M55V polymorphism with autoimmune diabetes in Latvian patients.

Small ubiquitin-related modifier (SUMO4), located in IDDM5, has been identified as a potential susceptibility gene for type 1 diabetes mellitus (T1DM). The novel polymorphism M55V, causing an amino acid change in the evolutionarily conserved met55 residue has been shown to activate the nuclear factor kappaB (NF-kappaB), hence the suspected role of SUMO4 in the pathogenicity of T1DM. The M55V polymorphism has been shown to be associated with susceptibility to T1DM in Asians, but not in Caucasians. Latent autoimmune diabetes in adults (LADA) is a slowly progressive form of T1DM and SUMO4 M55V has not been studied in LADA to date. The current study aims to test whether Latvians are similar to Caucasians in susceptibility to autoimmune diabetes (T1DM and LADA), with respect to SUMO4 M55V. We studied, age- and sex-matched, Latvian T1DM patients (n = 100) and healthy controls (n = 90) and LADA patients (n = 45) and healthy controls (n = 95). SUMO4 M55V polymorphism was analyzed using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP). The allelic frequencies of the A and G alleles were compared with HLA DR3-DR4-positive and HLA DR3-DR4-negative patients to identify any potential relation between HLA DR3-DR4 and SUMO4 M55V. We found no significant association between SUMO4 M55V and T1DM susceptibility in Latvians, the results being in concurrence with the previous studies in Caucasians of British and Canadian origin. Comparison of the A and G alleles with HLA DR3-DR4 did not result in any significant P values. No significant association was found between SUMO4 M55V and LADA. SUMO4 M55V is not associated with susceptibility to T1DM and LADA in Latvians, and Latvians exhibit similarity to other Caucasians with respect to association of SUMO4 M55V with autoimmune diabetes.

The Pediatric Rheumatology International Trials Organization criteria for the evaluation of response to therapy in juvenile systemic lupus erythematosus: prospective validation of the disease activity core set.

OBJECTIVE: To validate and promulgate a core set of outcome measures for the evaluation of response to treatment in patients with juvenile systemic lupus erythematosus (SLE). METHODS: In 2001, a preliminary consensus-derived core set of measures for evaluating the response to therapy in juvenile SLE was established. In the present study, the core set was validated through an evidence-based, large-scale data collection process that led to the enrollment of 557 patients from 39 different countries. Consecutive patients with active disease were assessed at baseline and after 6 months. The validation procedures included assessment of feasibility, responsiveness, discriminant and construct ability, agreement in the evaluation of response to therapy between physicians and parents, redundancy, internal consistency, and ability to predict a therapeutic response. RESULTS: The following clinical measures were found to be feasible and to have good construct validity, discriminative ability, and internal consistency; furthermore, they were not redundant, proved responsive to clinically important changes in disease activity, and were associated strongly with treatment outcome and thus were included in the final core set: 1) physician's global assessment of disease activity, 2) global disease activity measure, 3) 24-hour proteinuria, 4) parent's global assessment of the patient's overall well-being, and 5) health-related quality of life assessment. CONCLUSION: The members of PRINTO propose a core set of criteria for the evaluation of response to therapy that is scientifically and clinically relevant and statistically validated. The core set will help standardize the conduct and reporting of clinical trials and assist practitioners in deciding whether a patient with juvenile SLE has responded adequately to therapy.

Previous antibacterial treatment due to concomitant infections in preschool children is associated with a lower Helicobacter pylori positivity.

Use of antimicrobial agents has been proposed as 1 of the factors that contribute to the loss of Helicobacter pylori (H. pylori) infection. The aim of the study was to investigate the influence of a previous treatment with antibiotics on the prevalence of H. pylori infection in preschool children. Parents of 146 asymptomatic children (aged 0.5-5 y; no antibiotic treatment during the previous 4 weeks) completed a questionnaire about previous treatment with antibiotics and socioeconomic status. Infection with H. pylori was assessed by the monoclonal stool antigen test. H. pylori positivity was 18% (27/146). It was significantly lower in children who had been treated with antibiotics previously compared to those who had been never treated (12.5% (12/96) vs 30% (15/50), p=0.01). It is concluded that previous antibiotic treatment for concomitant infections is associated with a lower prevalence of H. pylori infection in preschool children.

Killer cell immunoglobulin-like receptor genes in Latvian patients with type 1 diabetes mellitus and healthy controls.

T1DM is very common in Sweden and is positively associated with HLA class II genes. Approximately 89% of the newly diagnosed patients carry the high-risk HLA DR4-DQ8 and DR3-DQ2. The remaining 11% develop T1DM without them. This can be due to involvement of other genes and environmental factors. Natural killer (NK) cells of the innate immune system are important in antiviral and antitumor immunity. They are implicated in the etiology of autoimmune T1DM. Human NK cells express killer cell immunoglobulin-like receptors (KIR) that belong to the polymorphic multigene family in chromosome 19q3.4. They modulate NK cell response by interacting with HLA class I. In addition, polymorphic MICA in HLA class I interacts with non-polymorphic NKG2D receptor on NK cells. We have studied, in addition to HLA-DR and -DQ, genes of the innate immune system MICA and KIR in Latvian patients (n = 98) with T1DM and controls (n = 100). They were genotyped using standard PCR-based typing methods. MICA allele 5 is positively associated with T1DM. KIR2DL2 and KIR2DS2 were both positively associated. Combined association of MICA4 and KIR2DL2 gave an odds ration (OR) of 26.7. However, the combined risk of KIR2DL2 and HLA class II genes, HLADR3 (OR = 73.4), DR4 (OR = 66.8), and DR3 and DR4 (OR = 88.3), was higher. The maximum risk was when KIR2DL2, MICA5, and DR3/DR4 were in combination. In conclusion, our results suggest that a balance between innate and acquired immunity is important, and an imbalance coud lead to T1DM.

Major histocompatibility complex class I chain related (MIC) A gene, TNFa microsatellite alleles and TNFB alleles in juvenile idiopathic arthritis patients from Latvia.

In order to analyze involvement of major histocompatibility complex class I chain-related gene A (MICA) and tumor necrosis factor a (TNFa) microsatellite polymorphisms as well as TNFB gene in juvenile idiopathic arthritis (JIA), we studied 128 patients divided into groups according to clinical features [monoarthritis (n = 14), oligoarthritis (n = 58), polyarthritis (n = 50), and systemic (n = 6)], and 114 age- and sex-matched healthy controls from Latvia. DNA samples were amplified with specific primers and used for genotyping of MICA and TNFa microsatellite. Typing for a biallelic NcoI polymerase chain reaction RFLP polymorphism located at the first intron of TNFB gene was done as follows: restriction digests generated fragments of 555bp and 185bp for TNFB*1 allele, and 740bp for TNFB*2 allele. The results were compared between cases and controls. We found significant increase of MICA allele A4 (p = 0.009; odds ratio [OR] = 2.3) and allele TNFa2 (p = 0.0001; OR = 4.4) in patients compared with controls. The frequency of allele TNFa9 was significantly decreased (p = 0.0001; OR = 0.1) in patients with JIA. No significant differences of TNFB allele frequency were found. Our data suggest that MICA and TNFa microsatellite polymorphisms may be used as markers for determination of susceptibility and protection from JIA.