Investigação de polimorfismos no gene MEFV (G138G e A165A) em pacientes adultos com febre mediterrânica familiar

MEFV gene allele frequency and genotype distribution in 3230 patients' analyses by next generation sequencing methods

Familial Mediterranean Fever (FMF, OMIM ID: 249100) is the most common autoinflammatory, autosomal recessive disease caused by mutations in the MEFV gene. It is widespread in the Mediterranean, primarily among Turkish, Armenian, Arab and Jewish. This study aims to examine genotype distributions of common MEFV variants in the Turkish population using targeted NGS and to evaluate all rare mutations. It included 3230 people applying to Ege University Children's Hospital Molecular Medicine Laboratory with the suspicion of autoinflammatory disease between 2017 and 2021. MEFV missense variant was detected in 1839 (56.9%) individuals. One or more mutations were found in them. 1063 patients were heterozygous (57.8%), 410 were compound heterozygous (22.3%), 238 were complex genotype (12.9%), and 128 were homozygous (7%). 56 different mutations and 141 genotypes were detected, two of which were novel (p.His87Arg, c.260A > G and p.Leu396Phe, c.1186C > T). These were determined as 6benign, 40 uncertain significant, 3 likely pathogenic and 7 pathogenic according to the ACMG classification. The most common ones were R202Q (n = 1097, 37.48%), E148Q (n = 512, 17.49%), M694V (n = 493, 16.84%), V726A (n = 155, 5.30%), M680I (n = 150, 5.12%), P369S (n = 108, 3.69%), R408Q (n = 95, 3.25%) respectively. They constitute 89.17 % of the entire patient population. In conclusion, DNA variants/mutations in the MEFV gene were evaluated in 3230 patients. To date, no mutation screening has been encountered in such a large population using NGS. Genotype distributions of both common and rare mutations were revealed. The obtained data will hopefully contribute to the future genotype-phenotype studies of FMF disease.

Genetic aspects of idiopathic paediatric uveitis and juvenile idiopathic arthritis associated uveitis in Chinese Han

Background

Idiopathic paediatric uveitis (IPU) and juvenile idiopathic arthritis associated uveitis (JIA-U) are the two most common entities in paediatric uveitis. This study addressed the possible association of IPU and JIA-U with genes that had been shown earlier to be associated with juvenile idiopathic arthritis.

Methods

We carried out a case-control association study involving 286 IPU, 134 JIA-U patients and 743 healthy individuals. A total of 84 candidate single nucleotide polymorphisms (SNPs) in 60 genes were selected for this study. The MassARRAY platform and iPLEX Gold Genotyping Assay was used to genotype 83 candidate SNPs and the remaining SNP (rs27293) was analysed using the TaqMan SNP Genotyping Assay.

Results

No evidence was found for an association of the candidate polymorphisms tested with IPU. Six SNPs (PRM1/rs11074967, JAZF1/rs73300638, IRF5/rs2004640, MEFV/rs224217, PSMA3/rs2348071 and PTPN2/rs7234029) showed an association with JIA-U (p<1.0×10⁻²).

Conclusion

Our findings showed associations of six SNPs (PRM1/rs11074967, JAZF1/rs73300638, IRF5/rs2004640, MEFV/rs224217, PSMA3/rs2348071 and PTPN2/rs7234029) with JIA-U. No association was detected between the 84 tested SNPs and IPU.

Clinical and Demographic Evaluation According to MEFV Genes in Patients with Familial Mediterranean Fever

The present study examined the relationship between clinical findings and mutation analyses in children with Familial Mediterranean Fever (FMF) in the inner Black Sea region of Turkey. This retrospective, cross-sectional study included patients with FMF who were evaluated between 2007 and 2015. FMF was diagnosed according to the Tel Hashomer criteria. FMF mutations were analyzed using a Real-time PCR System (Roche Diagnostics, Mannheim, Germany), and patients were classified into three groups according to allele status. The most common symptom was abdominal pain (99%, n = 197). The most frequent mutations were M694V and R202Q. Chest pain was reported more often in patients homozygous for M694V (61.4%). Although fever, abdominal pain, and arthritis were more commonly observed with the M694V mutation, chest pain was the most common symptom in R202Q carriers (n = 10, 32.3%). Proteinuria was observed in 42 (21.2%) patients, frequently accompanied by the M694V mutation (28.6%). The most common mutations in children with FMF in Turkey were M694V and R202Q. Recurrent abdominal pain and arthritis/arthralgia were commonly observed in patients with M694V and R202Q mutations. Moreover, chest pain was commonly seen with the R202Q mutation. Thus, R202Q might be a disease-causing mutation in FMF patients.

Clinical outcomes and survival in AA amyloidosis patients

AIM

Amyloid A amyloidosis is a rare complication of chronic inflammatory conditions. Most patients with amyloid A amyloidosis present with nephropathy and it leads to renal failure and death. We studied clinical characteristics and survival in patients with amyloid A amyloidosis.

METHODS

A total of 81 patients (51 males, 30 females) with renal biopsy proven amyloid A amyloidosis were analyzed retrospectively. The patients were divided into good and poor outcomes groups according to survival results.

RESULTS

Most of the patients (55.6%) had nephrotic range proteinuria at diagnosis. Most frequent underlying disorders were familial Mediterranean fever (21.2%) and rheumatoid arthritis (10.6%) in the good outcome group and malignancy (20%) in the poor outcome group. Only diastolic blood pressure in the good outcome group and phosphorus level in the poor outcome group was higher. Serum creatinine levels increased after treatment in both groups, while proteinuria in the good outcome group decreased. Increase in serum creatinine and decrease in estimated glomerular filtration rate of the poor outcome group were more significant in the good outcome group. At the time of diagnosis 18.5% and 27.2% of all patients had advanced chronic kidney disease (stage 4 and 5, respectively). Median duration of renal survival was 65±3.54 months. Among all patients, 27.1% were started dialysis treatment during the follow-up period and 7.4% of all patients underwent kidney transplantation. Higher levels of systolic blood pressure [hazard ratios 1.03, 95% confidence interval: 1-1.06, p=0.036], serum creatinine (hazard ratios 1.25, 95% confidence interval: 1.07-1.46, p=0.006) and urinary protein excretion (hazard ratios 1.08, 95% confidence interval: 1.01-1.16, p=0.027) were predictors of end-stage renal disease. Median survival of patients with organ involvement was 50.3±16 months.

CONCLUSION

Our study indicated that familial Mediterranean fever constituted a large proportion of cases and increased number of patients with idiopathic amyloid A amyloidosis. Additionally, it was observed that patient survival was not affected by different etiological causes in amyloid A amyloidosis.