Genotype-phenotype correlation in a large group of Turkish patients with familial mediterranean fever: evidence for mutation-independent amyloidosis

OBJECTIVES: Differences in clinical manifestations of familial Mediterranean fever (FMF) between different ethnic groups have been documented. The FMF gene was recently cloned and four missense mutations (Met694Val, Met680Ile, Val726Ala, and Met694Ile) that account for a large percentage of the patients were identified. The results of initial mutation studies have led to the hypothesis that phenotypic variation of the disease may be attributable to the existence of some of these mutations. The purpose of this study was to evaluate whether this phenotypic variation is associated with the existence of particular mutations in Turkish FMF patients living in Turkey. METHODS: Four missense mutations and genotype-phenotype correlation were investigated in 167 Turkish FMF patients. The patients were grouped according to the presence of the Met694Val and the Met680Ile mutations, and 12 clinical parameters were compared between the groups. RESULTS: The presence of the Met694Val mutation was not found to be associated with a severe form of the disease or the development of amyloidosis. Arthritis frequency was found to be lower in the patients with homozygous Met680Ile mutation. CONCLUSIONS: None of the four missense mutations is associated with a severe disease or the development of amyloidosis in Turkish FMF patients living in Turkey. The influence of unknown environmental factors and/or the presence of other genetic changes are necessary to explain the phenotypic variation of the disease and the development of amyloidosis.     

Serum amyloid A1 and tumor necrosis factor-alpha alleles in Turkish familial Mediterranean fever patients with and without amyloidosis.

The major complication of familial Mediterranean fever (FMF) is AA amyloidosis. The influence of FMF gene (MEFV) mutations and/or unknown environmental factors and other genetic modifiers are likely to affect the phenotypic variations of the disease and the development of amyloidosis. Serum amyloid A is a serum precursor of AA amyloid that is induced by inflammatory cytokines including TNF-alpha. Our analysis of SAA1.1 frequency in Turkish FMF-amyloidosis patients, revealed a higher frequency compared to non FMF-amyloidosis patients but the difference was not significant. On the other hand, the distribution of SAA1.1 homozygosity among FMF-amyloidosis patients was 55.5% compared to FMF-non-amyloidosis patients (30.8%) which was statistically significant revealing a 2.5 fold risk for the occurrence of amyloidosis. There was no significant difference between the controls and FMF patients with and without amyloidosis for the TNF-alpha-308 G-A allele. It is worth noting that all TNF-alpha-308 G-A carriers (n = 6) in FMF-amyloidosis group have SAA1.1 homozygosity compared to 2/11 in FMF-non-amyloidosis group. Further evaluation of these polymorphisms may have importance and need further study.     

SAA1 gene polymorphisms and the risk of AA amyloidosis in Japanese patients with rheumatoid arthritis

To investigate the precise modality of association between SAA1 gene polymorphisms and the development of AA amyloidosis in patients with rheumatoid arthritis (RA), Japanese patients with RA (n = 153), among whom 29 were histologically diagnosed as having amyloidosis, were genotyped for three single nucleotide polymorphisms (SNPs), C-13T, C2995T, and C3010T, in the SAA gene. Pairwise linkage disequilibrium coefficients between each pair of SNPs were calculated and estimated haplotype frequencies were compared between patients with and without amyloidosis. Possible associations between these SNPs and amyloidosis were analyzed by a case–control study and by the Kaplan–Meier method, in which the endpoint was defined as the time of diagnosis of AA amyloidosis. The -13T and 2995C alleles, which were in a tight linkage disequilibrium, were more frequent in the patients with amyloidosis, and the groups with the -13TT and 2995CC genotype had worse survival curves than patients without these genotypes, whereas C3010T was not associated with amyloidosis. Moreover, the haplotype containing −13C and 2995T was found to be protective. Both C-13T and C2995T were associated with the development of amyloidosis. Examining both polymorphisms may be more useful than examining only one of them for estimating the risk of the development of amyloidosis.     

SAA1 gene polymorphisms and the risk of AA amyloidosis in Japanese patients with rheumatoid arthritis

Abstract

To investigate the precise modality of association between SAA1 gene polymorphisms and the development of AA amyloidosis in patients with rheumatoid arthritis (RA), Japanese patients with RA (n = 153), among whom 29 were histologically diagnosed as having amyloidosis, were genotyped for three single nucleotide polymorphisms (SNPs), C-13T, C2995T, and C3010T, in the SAA gene. Pairwise linkage disequilibrium coefficients between each pair of SNPs were calculated and estimated haplotype frequencies were compared between patients with and without amyloidosis. Possible associations between these SNPs and amyloidosis were analyzed by a case–control study and by the Kaplan–Meier method, in which the endpoint was defined as the time of diagnosis of AA amyloidosis. The -13T and 2995C alleles, which were in a tight linkage disequilibrium, were more frequent in the patients with amyloidosis, and the groups with the -13TT and 2995CC genotype had worse survival curves than patients without these genotypes, whereas C3010T was not associated with amyloidosis. Moreover, the haplotype containing ?13C and 2995T was found to be protective. Both C-13T and C2995T were associated with the development of amyloidosis. Examining both polymorphisms may be more useful than examining only one of them for estimating the risk of the development of amyloidosis.     

The contribution of genotypes at the MEFV and SAA1 loci to amyloidosis and disease severity in patients with familial Mediterranean fever

OBJECTIVE: The clinical profile in familial Mediterranean fever (FMF), including its major manifestation, amyloidosis, is influenced by MEFV allelic heterogeneity and other genetic and/or environmental factors. In this study, we analyzed the contribution of genotypes at the MEFV and SAA1 loci to disease severity and to the development of amyloidosis, and further defined the factors affecting the clinical profile of FMF. METHODS: We investigated a sample of 277 FMF patients (154 men and 123 women), including 62 patients with nephropathic amyloidosis, in whom both FMF alleles had been identified. A detailed chart review, interview, and physical examination were undertaken to determine the patients' demographic characteristics, medical history, clinical manifestations, and treatment. The disease severity score was calculated from the Tel-Hashomer key. Genotypes at the SAA1 locus (isoforms alpha, beta, and gamma) were determined in all patients. The SAA1 13C/T polymorphism of the SAA1 promotor was analyzed in a subset of cases. RESULTS: The male:female ratio (154:123, or 1.3) was higher among patients with amyloidosis (40:22, or 1.8) compared with patients without amyloidosis (114:101, or 1.1). Logistic regression analysis showed that homozygosity for the M694V allele (odds ratio [OR] 4.27, 95% confidence interval [95% CI] 2.01-9.07), the presence of the SAAalpha/alpha genotype (OR 2.99, 95% CI 1.47-6.09), the occurrence of arthritis attacks (OR 2.43, 95% CI 1.17-5.06), and male sex (OR 1.73, 95% CI 0.90-3.33) were significantly and independently associated with renal amyloidosis. Disease severity was mainly influenced by MEFV mutations and was not associated with genotypes at the SAA1 locus. The SAA1 13T allele was rare, being associated mainly with the SAA gamma isoform, and not related to renal amyloidosis. CONCLUSION: Overall, disease severity and the development of amyloidosis in FMF are differentially affected by genetic variations within and outside the MEFV gene.     

Association of (-1,607) 1G/2G polymorphism of matrix metalloproteinase-1 gene with knee osteoarthritis in the Turkish population (knee osteoarthritis and MMPs gene polymorphisms)

The aim of this study was to investigate whether functional polymorphisms in the promoter of matrix metalloproteinase-1 (MMP-1), MMP-2 and MMP-9 genes were associated with susceptibility to knee osteoarthritis in the Turkish population. The MMP-1 −1,607 1G/2G (rs1799750), MMP-2 −1,306 C/T (rs243865), and MMP-9 −1,562 C/T (rs3918242) polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism assay in 157 patients diagnosed with knee osteoarthritis based on the criteria of American College of Rheumatology and in 84 controls in Mersin, Turkey. Genotype distributions and allele frequencies of MMP-1, MMP-2, and MMP-9 gene polymorphisms were compared between the patients and controls. There were significant differences between the groups regarding the genotype distribution of MMP-1 polymorphism (P  = 0.001). The frequencies of 1G/1G and 1G/2G genotypes were significantly higher in the knee osteoarthritis than in the controls (P = 0.002, and P =  0.006, respectively). In addition, 1G allele frequency of MMP-1 gene was higher in the patients than in the control group (P = 0.0001). The genotype distributions and allele frequencies of MMP-2 and MMP-9 gene polymorphisms did not differ between the osteoarthritis and the control groups (P > 0.05). These findings suggest that the −1,607 1G/2G polymorphism in the MMP-1 gene may contribute to susceptibility to knee osteoarthritis in the Turkish population.     

The rate and significance of type 1/type 2 serum amyloid A protein gene polymorphisms in patients with ankylosing spondylitis and amyloidosis

A relationship between the presence of amyloidosis and SAA1 genotype has been shown in recent studies of (principally) familial Mediterranean fever patients. We found that the SAA1 rs12218 polymorphism was significantly more prevalent in ankylosing spondylitis patients with amyloidosis.     

Serum C-reactive protein is rarely lost into urine in patients with secondary amyloidosis and proteinuria

We studied whether the low serum C-reactive protein (S-CRP) level in patients with inflammatory arthritis and proteinuria was due to the loss of CRP into urine. In 19 patients with secondary amyloidosis (14 with rheumatoid arthritis and five with juvenile chronic arthritis), S-CRP was measured with both immunoturbidimetric and radioimmunoassays. The concentration of urinary CRP was measured with a double-antibody radioimmunoassay. One patient with the most extensive proteinuria (12 g/24 h) excreted CRP at 14 mg/24 h, while in 18 of 19 patients only negligible, if any, amounts of CRP were found in 24-h urine samples. Proteinuria of <8 g/24 h did not reduce the S-CRP level. Proteinuria exceeding this level may result in increased excretion of CRP into urine and consequently may result in a reduced S-CRP level.     

Efficacy and safety of interleukin-1 inhibitors in familial Mediterranean fever patients complicated with amyloidosis

Abstract

Background: Colchicine is the mainstay of the treatment of familial Mediterranean fever (FMF). However, 10% of FMF patients do not respond well to colchicine. Efficacy of interleukin (IL)-1 inhibitors in reducing attacks have been demonstrated in colchicine-resistant FMF (crFMF) patients recently. Colchicine is still the only approved drug for the prevention of amyloidosis in FMF and utility of IL-1 inhibitors in crFMF cases who already has amyloidosis remain to be elucidated. Herein, we evaluated efficacy and safety of IL-1 inhibitors in patients with crFMF-associated AA amyloidosis in a relatively large single center study.

Methods: Medical records of FMF patients complicated with AA amyloidosis in our dedicated FMF center were retrospectively reviewed and those patients who ever treated with IL-1 inhibitors were enrolled into the study. Patient global, physician global assessments (on 0–10?cm visual analog scale), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), serum creatinine and 24-h urinary protein excretion values for each visit were recruited from computer-based hospital records. Treatment response of patients were assessed with clinical symptoms, serum albumin, CRP and ESR values. Renal outcome parameters were analyzed on those not receiving renal replacement therapy.

Results: Seventeen patients were identified with crFMF-amyloidosis that ever treated with IL-1 inhibitors. Background colchicine therapy was continued in all patients in maximal-tolerated dose along with IL-1 inhibitors. All patients benefit from IL-1 antagonists assessed by patient and physician global assessments. Inflammatory markers, CRP and ESR, were significantly reduced in all and normalized in 12 out of 17 patients. More importantly, the amount of proteinuria was remarkably improved following IL-1 inhibitor therapy (1606?mg/day to 519?mg/day, p?=?.008). Both anakinra and canakinumab were well-tolerated without severe side effects. All patients were initially treated with anakinra but switched to canakinumab in seven patients (one leukopenia, four injection site reaction, two inefficacy).

Conclusion: We evaluated the clinical and laboratory responses to IL-1 inhibitors in crFMF-associated amyloidosis patients. We found significant decreases in CRP, ESR and proteinuria after IL-1 inhibitor therapy. This study confirmed that IL-1 inhibitors are effective for controlling attacks and inflammatory activity in FMF patients complicated with AA amyloidosis. Moreover, they reduce or stabilize amount of proteinuria and preserve renal function in short-term follow-up. Prolonged prospective clinical trials are warranted to assess their long-term efficacy in this particular patient group.     

Analysis of SAA1 gene polymorphisms in the Greek population: rheumatoid arthritis and FMF patients relative to normal controls. Homogeneous distribution and low incidence of AA amyloidosis

Objective. To address whether or not the rarity of amyloidosis in Greek patients with rheumatoid arthritis (RA) is related to specific alleles of single nucleotide polymorphisms (SNPs) in the 5′-flanking region and the exon 3 of the SSA1 gene.

Methods. The genotypes of the ?13T/C SNP in the 5′-flanking region of the SAA1 gene and the two SNPs within exon 3 of SAA1 (2995C/T and 3010C/T polymorphisms) were determined in 88 Greek patients with RA, 14 patients with familial Mediterranean fever (FMF) and 110 healthy controls. Linkage disequilibrium and haplotype frequencies involving ?13T/C, 2995C/T and 3010C/T in these populations were tested and estimated, respectively.

Results. The genotypic distribution and allelic frequencies were similar in all groups tested. SNPs 2995 and 3010 were in linkage disequilibrium for all study populations (p < 0.05), whereas SNP ?13 was not in linkage disequilibrium with either 2995 or 3010 (p ≥ 0.05). Two major haplotypes presented in all patients with RA and FMF and controls: ?13C; 2995T; 3010C (?13C; α) and ?13C; 2995C; 3010T (?13C; β). The ?13T allele was linked with the γ haplotype in Greek patients with RA and controls. The frequency of the ?13T allele was found to be very rare in all groups tested.

Conclusions. In conclusion, the rarity of the putative amyloidogenic ?13T allele in Greek populations may be related to low prevalence of AA amyloidosis development in Greek RA patients.     

Interleukin-1 receptor antagonist (IL-1RN) and interleukin-1B gene polymorphisms in Turkish patients with rheumatoid arthritis

OBJECTIVE: Interleukin 1 (IL-1) family is composed of two agonists, IL-1alpha and IL-1Beta and IL-1 receptor antagonist, IL-1Ra. The purpose of this study was to determine the relationship between polymorphisms of IL-1 receptor antagonist (IL-1RN), IL-1B promoter and IL-1B exon 5 genes and susceptibility to rheumatoid arthritis (RA) in Turkish population. METHODS: Polymerase chain reaction (PCR) was used to determine the genotype of the IL-1RN for 94 RA patients and 104 healthy controls. Genotyping of IL-1B polymorphisms at positions -511 (C/T) and +3953 (C/T) was detected by PCR followed restriction fragment length analysis. RESULTS: There was no significant difference in IL-1RN genotype and allele distributions between RA and the control groups. In addition, no significant association was observed in the allelic frequency (C or T) of IL-1B promoter (-511) between RA patients and the controls (P = 0,118), but the genotype distribution of 1/2 (C/T) at position -511 showed a significant difference (P = 0,038). Also, 2/2 genotype (T/T); (P = 0,028), and allele 2 (T) distribution (P = 0,011) of IL-1B (+3953) showed significant differences between RA patients and the control groups in the study population. CONCLUSION: These results imply that 2/2 (T/T) genotype or allele 2 (T) of IL-B (+3953) are susceptibility factors for RA in Turkey. Also, 1/2 genotype (C/T) of IL-1 -511 can play a protective role for RA.     

Analysis of SAA1 gene polymorphisms in the Greek population: rheumatoid arthritis and FMF patients relative to normal controls. Homogeneous distribution and low incidence of AA amyloidosis.

OBJECTIVE: To address whether or not the rarity of amyloidosis in Greek patients with rheumatoid arthritis (RA) is related to specific alleles of single nucleotide polymorphisms (SNPs) in the 5'-flanking region and the exon 3 of the SSA1 gene. METHODS: The genotypes of the -13T/C SNP in the 5'-flanking region of the SAA1 gene and the two SNPs within exon 3 of SAA1 (2995C/T and 3010C/T polymorphisms) were determined in 88 Greek patients with RA, 14 patients with familial Mediterranean fever (FMF) and 110 healthy controls. Linkage disequilibrium and haplotype frequencies involving -13T/C, 2995C/T and 3010C/T in these populations were tested and estimated, respectively. RESULTS: The genotypic distribution and allelic frequencies were similar in all groups tested. SNPs 2995 and 3010 were in linkage disequilibrium for all study populations (p < 0.05), whereas SNP -13 was not in linkage disequilibrium with either 2995 or 3010 (p > or = 0.05). Two major haplotypes presented in all patients with RA and FMF and controls: -13C; 2995T; 3010C (-13C; alpha) and -13C; 2995C; 3010T (-13C; beta). The -13T allele was linked with the gamma haplotype in Greek patients with RA and controls. The frequency of the -13T allele was found to be very rare in all groups tested. CONCLUSIONS: In conclusion, the rarity of the putative amyloidogenic -13T allele in Greek populations may be related to low prevalence of AA amyloidosis development in Greek RA patients.     

Identification of polymorphisms on the MDR1 gene among Turkish population and their effects on multidrug resistance in acute leukemia patients

Multidrug-resistance (MDR) phenotype is a serious limitation to the effective chemotherapeutic treatment of many cancer types, including leukemia. One of the most important proteins, the over-expression of which is responsible for the multidrug-resistance phenotype in many cancer types, is P-glycoprotein. This protein is the product of the MDR1 gene. In previous studies, single-nucleotide polymorphisms (SNPs) C3435T, G2677T, and T-129C in the MDR1 gene were shown to be correlated with lower P-glycoprotein expression in normal tissues. It was suggested that this might have an advantage in cancer chemotherapy by resulting in a low drug-resistance phenotype. The frequencies of these SNPs were studied in 45 acute leukemia patients (25 of which were primary refractory and 20 of which were drug-sensitive) and 17 healthy individuals, forming a Turkish population of 62 individuals. In the first part of the study, these polymorphisms were compared with other populations. Marked differences were apparent between African and Turkish populations for the C3435T polymorphism. On the other hand, similarities were found between other Caucasian/Asian and Turkish populations (P < 0.001). However, for the G2677T polymorphism, the Turkish population is different than Japanese and German populations (P < 0.001). For the T-129C polymorphism, all individuals in the studied population were homozygous for the T/T genotype. In the second part of this study, drug-resistant and drug-sensitive acute leukemia patients were compared for these SNPs. These polymorphisms did not seem to have a significant effect on P-glycoprotein-mediated drug resistance in the patients studied.     

NOD2/CARD15, NOD1/CARD4, and ICAM-1 gene polymorphisms in Turkish patients with inflammatory bowel disease

Purpose The genetic susceptibility of people with certain NOD2/CARD15, NOD1/CARD4, and ICAM-1 gene variants to inflammatory bowel disease is still under investigation. The aim of this study was to investigate polymorphisms in the NOD2/CARD15 (R702W, G908R, and 3020insC), NOD1/CARD4 (E266K, D372N), and ICAM-1 (G241R, K469E) genes, which are known to be associated with inflammation, in Turkish patients with inflammatory bowel disease and healthy control groups. Methods The genotypes of 70 patients with endoscopically and histopathologically diagnosed Crohn's disease (38 men, 32 women; mean age, 38.8 ± 1.3), 120 patients with ulcerative colitis (67 men, 53 women; mean age, 41.7 ± 1.3) and 106 healthy control subjects (37 men, 69 women; mean age, 35.7 ± 1.4), who stated that they had never had any prior bowel disease history, were compared. A polymerase chain reaction-restriction fragment length polymorphism analysis was performed for two variants of the ICAM-1 gene, the three main variants of the NOD2/CARD15 gene, and the E266K variant of the NOD1/CARD4 gene, and DNA sequencing was used for the D372N polymorphism of the NOD1/CARD4 gene. Results In this study, the three previously described Crohn's disease-predisposing variants of the NOD2/CARD15 gene and the polymorphisms examined in the NOD1/CARD4 and ICAM-1 genes were not found to be associated with ulcerative colitis or Crohn's disease. Conclusions These findings suggest that the polymorphisms observed in the NOD2/CARD15, NOD1/CARD4, and ICAM-1 genes are not genetic susceptibility factors for Crohn's disease or ulcerative colitis in Turkey.     

Effect of etanercept on serum amyloid A protein (SAA) levels in patients with AA amyloidosis complicating inflammatory arthritis

We assessed changes in serum amyloid A protein (SAA) levels during treatment with etanercept in AA amyloidosis complicating inflammatory arthritis. Five women and four men with AA amyloidosis and inflammatory arthritis received etanercept. SAA levels were recorded before and after commencement of treatment. Previous immunosuppressive drugs included cyclophosphamide (four patients), azathioprine (three patients), methotrexate (two patients) and chlorambucil (in one patient). Two patients received no disease modifying drugs between the time of diagnosis of AA amyloidosis and commencement of etanercept. In seven out of nine patients the median SAA level during etanercept treatment was lower than levels before anti-tumour necrosis factor therapy. In five out of nine patients, the median post treatment level was <11 mg/l. There were no significant changes in serum creatinine or proteinuria during periods (median, 23 months; range, 1-24 months) of etanercept therapy. The etanercept was stopped in four patients because of: acute bacterial endocarditis, psoriasiform rash, psychosis and leukopenia. In two of these patients alternative biologics were commenced (adalimumab or anakinra) and one was restarted on etanercept. One patient died of cerebral haemorrhage during the study. Etanercept therapy was associated with a fall in SAA levels in seven of nine patients, five of whom achieved levels which might be expected to be associated with stable or regressing amyloid deposits. Etanercept represents a useful alternative to immunosuppressant therapy such as cyclophosphamide or chlorambucil. Further work is needed to establish whether organ damage related to AA amyloidosis is slowed by etanercept.     

Serum IL 4 and its gene polymorphism (rs79071878) in Egyptian children with familial Mediterranean fever

Clinical Rheumatology - Familial Mediterranean fever (FMF) is an autoinflammatory disorder. It is caused by mutations in the MEFV gene encoding the pyrin protein, which regulates the innate...     

Amyloid goitre in familial Mediterranean fever: report on three patients and review of the literature

Familial Mediterranean fever (FMF) is a hereditary disease, the most threatening complication of which is systemic amyloidosis. The thyroid gland may be asymptomatically involved in most patients with systemic amyloidosis secondary to FMF. However, clinically detectable thyroid goitre is quite rare, and until now only nine cases of thyroid goitre secondary to amyloid deposition in FMF have been reported. Of 1,100 FMF patients regularly followed up at our centre, thyroid goitre due to the accumulation of amyloid substance could be detected in only three (0.27%). In this report, we summarise the clinical and laboratory features of these patients. All three patients were euthyroid. Total thyroidectomy was performed for compressive symptoms in one patient and for aesthetic purposes in the other two. In countries with a high prevalence of FMF, such as Turkey, secondary amyloidosis of the thyroid gland should be borne in mind in long-standing FMF patients.