Galectin-3: a new biomarker for differentiating periodic fever, adenitis, pharyngitis, aphthous stomatitis (PFAPA) syndrome from familial Mediterranean fever?

Differentiating PFAPA (periodic fever, aphthosis, pharyngitis, and adenitis) syndrome from familial Mediterranean fever (FMF) could be challenging in some cases. Galectin-3 is a lectin with regulatory functions in apoptosis and inflammation. We aimed to test whether galectin-3 could be a biomarker for differentiating PFAPA syndrome from FMF. Patients with PFAPA syndrome, FMF, cryopyrin-associated periodic syndrome (CAPS), and streptococcal pharyngitis, and healthy controls were included in this study. Serum galectin-3 levels were measured using enzyme-linked immunosorbent assay. Eighty-seven patients (36 with PFAPA, 39 with FMF, 8 with CAPS, 4 with streptococcal pharyngitis), and 17 healthy controls were included. Blood samples were drawn during attacks from 20 PFAPA and 7 FMF patients and attack-free periods from 22 PFAPA, 35 FMF, and 8 CAPS patients. The median serum galectin-3 level in the PFAPA-attack group (1.025 ng/ml) was significantly lower than the levels in healthy control (2.367 ng/ml), streptococcal pharyngitis (3.021 ng/ml), FMF attack (2.402 ng/ml), and FMF-attack-free groups (2.797 ng/ml) (p = 0.006, 0.03, 0.01, and < 0.001, respectively). PFAPA-attack-free group had lower galectin-3 levels than the FMF-attack-free group (1.794 vs. 2.797 ng/ml, respectively; p = 0.01). Galectin-3 levels did not differ significantly between CAPS and attack-free PFAPA patients (1.439 ng/ml vs. 1.794 ng/ml, respectively; p = 0.63). In our study, for the first time, we defined galectin-3 as a promising biomarker that differs between PFAPA and FMF patients during both disease flares and attack-free periods. Further studies with high number of patients could validate its role as a biomarker.

Phenotypical and Functional Characterization of Neutrophils in Two Pyrin-Associated Auto-inflammatory Diseases.

PURPOSE: Familial Mediterranean Fever (FMF) and Pyrin-Associated Autoinflammation with Neutrophilic Dermatosis (PAAND) are clinically distinct autoinflammatory disorders caused by mutations in the pyrin-encoding gene MEFV. We investigated the transcriptional, phenotypical, and functional characteristics of patient neutrophils to explore their potential role in FMF and PAAND pathophysiology. METHODS: RNA sequencing was performed to discover transcriptional aberrancies. The phenotypical features, degranulation properties, and phagocytic capacity of neutrophils were assessed by flow cytometry. Production of reactive oxygen species (ROS), myeloperoxidase (MPO) release, and chemotactic responses were investigated via chemiluminescence, ELISA, and Boyden chamber assays, respectively. RESULTS: Neutrophils from PAAND and FMF patients showed a partially overlapping, activated gene expression profile with increased expression of S100A8, S100A9, S100A12, IL-4R, CD48, F5, MMP9, and NFKB. Increased MMP9 and S100A8/A9 expression levels were accompanied by high plasma concentrations of the encoded proteins. Phenotypical analysis revealed that neutrophils from FMF patients exhibited an immature character with downregulation of chemoattractant receptors CXCR2, C5aR, and BLTR1 and increased expression of Toll-like receptor 4 (TLR4) and TLR9. PAAND neutrophils displayed an increased random, but reduced CXCL8-induced migration. A tendency for enhanced random migration was observed for FMF neutrophils. PAAND neutrophils showed a moderately but significantly enhanced phagocytic activity as opposed to neutrophils from FMF patients. Neutrophils from both patient groups showed increased MPO release and ROS production. CONCLUSIONS: Neutrophils from patients with FMF and PAAND, carrying different mutations in the MEFV gene, share a pro-inflammatory phenotype yet demonstrate diverse features, underscoring the distinction between both diseases.

The Value of Serum Amyloid A Levels in Familial Mediterranean Fever to Identify Occult Inflammation During Asymptomatic Periods.

OBJECTIVE: The aim of this observational study was to evaluate whether there was any correlation between the acute phase reactants in children with familial Mediterranean fever (FMF) during attack and attack-free periods. METHODS: The study was conducted between June 2016 and January 2018. Clinical features and laboratory parameters of children with FMF during attack and attack-free periods were recorded longitudinally. RESULTS: The cohort consisted of 168 children with FMF (84 boys, 84 girls). Median values of acute phase reactants during FMF attacks were 433.5 mg/L (34.0-1780.0 mg/L) for serum amyloid A (SAA), 56.7 mg/L (7.6-379.0 mg/L) for C-reactive protein (CRP), and 37.5 mm/h (5-100 mm/h) for erythrocyte sedimentation rate (ESR). Median values for the same tests in attack-free periods were 3.2 mg/L (0.1-25.0 mg/L), 1.7 mg/L (0.1-12.7 mg/L), and 8 mm/h (1-30 mm/h), respectively. Correlation analyses showed that SAA and CRP were highly correlated in FMF attack (r = 0.67, p < 0.01), but no correlation was found between SAA and ESR levels. C-reactive protein was elevated in 13.6%, ESR in 20.8%, and SAA in 28.5% of the patients during attack-free period. Age at onset, sex of the patients, and characteristics of attacks were found to be not associated with elevated SAA in attack-free period. On the other hand, having homozygous exon 10 mutation and having elevated CRP were found to be associated with high SAA in attack-free period. CONCLUSIONS: C-reactive protein and SAA correlate well with FMF attacks. Therefore, checking for SAA during a FMF attack is not required. However, SAA seems to be the most sensitive method for demonstrating subclinical inflammation in attack-free period. Thus, checking SAA levels might be a valuable tool in selected FMF patients.

The role of azurocidin in patients with familial Mediterranean fever and AA amyloidosis and its association with cardiovascular risk factors.

BACKGROUND: Familial Mediterranean fever (FMF) is characterized by sporadic, recurrent attacks of fever and serosal inflammation. AA amyloidosis (AAA) is a disorder characterized by the extracellular tissue deposition of serum amyloid A protein (SAA). Azurocidin is a neutrophil-derived granule protein. We aimed to investigate the significance of azurocidin in FMF and AAA and the correlation between azurocidin levels and carotid artery intima media thickness (CA-IMT) and cardiovascular plaque existence. METHODS: A sum of 52 FMF patients were enrolled in the study. FMF patients were composed of two groups. Group-1 included 30 patients with non-complicated FMF. Group-2 included 22 patients whom received renal transplantation due to FMF complicated with AAA and being followed up at stable state for at least one year. 24 healthy individuals who matched with FMF patients in terms of age and gender consisted the control group. RESULTS: We found statistically significant difference between patient and control groups in terms of urea (38.52 ± 19.96 mg/dl vs 29.08 ± 5.83 mg/dl; p = 0.003), creatinine (1.11 ± 0.39 mg/dl vs 0.91 ± 0.16 mg/dl; p = 0.002), serum uric acid (6.2 ± 2 mg/dl vs 4.5 ± 0.9 mg/dl; p < 0.001), serum CRP (8.62 ± 9.5 mg/dl vs 3.91 ± 3.9 mg/dl; p = 0.004), ferritin (151.4 ± 317 ng/ml vs 33.3 ± 34 ng/ml; p = 0.014), white blood cell (WBC) levels (7.97 ± 2.3 × 103/µL vs 6.6 ± 1.7 × 103/µL; p = 0.018), serum azurocidin levels (137.16 ± 65.62 ng/ml vs 102.35 ± 51.61 ng/ml; p = 0.015) and mean CA-IMT (0.57 ± 0.15 mm vs 0.47 ± 0.07 mm; p = 0.001). Comparison of group 1 and group 2 revealed statistically significant differences in terms of urea (26 ± 8 mg/dl vs 54 ± 19 mg/dl; p < 0.001), creatinine (0.87 ± 0.1 mg/dl vs 1.44 ± 0.3 mg/dl; p < 0.001), estimated glomerular filtration rate (eGFR) (99 ± 21 ml/min/1.73m2 vs 53 ± 16 ml/min/1.73m2; p < .001), uric acid (4.9 ± 1.3 mg/dl vs 7.6 ± 1.7 mg/dl; p < 0.001), ferritin (31.7 ± 27 ng/ml vs 292.8 ± 431 ng/ml; p = 0.010) and albumin (4.5 ± 0.3 g/dl vs 4.1 ± 0.3 g/dl; p = 0.001). There was no statistically significant difference between group 1 and group 2 in terms of mean CA-IMT (CA-IMT (M) (mm): 0.54 ± 0.14 vs 0.62 ± 0.17, p = 0.057). Serum azurocidin levels were not significantly different between group 1 and group 2 (121.73 ± 53.24 ng/ml vs 158.19 ± 75.77 ng/ml; p = 0.061). In multivariate linear regression analysis (variables: MBP, urea, creatinine, eGFR, ferritin, uric acid, CA-IMT) azurocidin was independently associated with urea (t:2.658; p = 0.010) and CA-IMT (t:2.464; p = 0.017). DISCUSSION: Based on our findings, azurocidin seems to be a good inflammation marker in patients with FMF. Increase in azurocidin levels might be associated with development of amyloidosis. Also, serum azurocidin levels may be used as a predictor of both inflammatory state and cardiovascular risk, especially when used with other markers such as CA-IMT.

Defining colchicine resistance/intolerance in patients with familial Mediterranean fever: a modified-Delphi consensus approach.

OBJECTIVES: Colchicine is the main treatment for FMF. Although a number of individuals with FMF are intolerant/resistant to colchicine, there is no standard definition of colchicine resistance/intolerance. We developed a set of evidence-based core statements defining colchicine resistance/intolerance in patients with FMF that may serve as a guide for clinicians and health authorities. METHODS: A set of statements was identified using a modified-Delphi consensus-based approach. The process involved development of an initial colchicine resistance/intolerance-related questionnaire derived from a systematic literature review. The questionnaire, which was completed by an international panel of 11 adult and paediatric rheumatologists with expertise in FMF, was analysed anonymously. The results informed draft consensus statements that were discussed by a round-table expert panel, using a nominal group technique to agree on the selection and wording of the final statements. RESULTS: Consensus among the panel was achieved on eight core statements defining colchicine resistance/intolerance in patients with FMF. A definition of resistance was agreed upon that included recurrent clinical attacks (average one or more attacks per month over a 3-month period) or persistent laboratory inflammation in between attacks. Other core statements recognize the importance of assessing treatment adherence, and the impact of active disease and intolerance to colchicine on quality of life. CONCLUSION: Based on expert opinion, a set of evidence-based core statements defining colchicine resistance/intolerance in patients with FMF were identified to help guide clinicians and health authorities in the management of patients with FMF.

Evaluation of serum CXC chemokine ligand 16 (CXCL16) as a novel inflammatory bio- marker or familial Mediterranean fever disease

Background/aim: Familial Mediterranean fever (FMF) is a disease that is mainly diagnosed with clinical features. Several well- known inflammatory markers increase in FMF. However, there is still a need for diagnostic tests for specifying FMF and monitoring inflammatory activity. CXCL16 is a chemokine produced by inflammatory cells that demonstrate efficacy in the acute phase response. In this study, we aimed to investigate the relationship between CXCL16 levels and FMF disease and to evaluate CXCL16 levels as a novel biomarker for FMF. Materials and methods: Fifty-three male patients diagnosed with FMF and sixty healthy individuals were included in this cross- sectional study. Blood samples were taken in the first 24 h of the attack periods. Serum soluble CXCL16 was evaluated by enzyme-linked immunosorbent assay (ELISA) method. Results: CXCL16 (P < 0.001), erythrocyte sedimentation rate (P < 0.001), C-reactive protein (P < 0.001), and fibrinogen (P = 0.005) were significantly higher in FMF group than in control group. Receiver operating characteristic (ROC) curve analysis revealed a cut off value of CXCL16 as 2.68 ng/ml with 83% sensitivity and 68% specificity (P < 0.001). Logistic regression analysis indicated that high CXCL16 and erythrocyte sedimentation rate levels were predictive parameters for FMF disease (OR 8.31; 95% CI 2.59-26.62; p <0.001) (OR 1.27; 95% CI 1.12-1.44; P < 0.001). There was no correlation between CXCL16 levels and attack frequency and disease duration (P = 0.395, P = 0.956). Conclusion: To the best of our knowledge, this is the first study evaluating serum soluble CXCL16 levels as a biomarker for FMF. CXCL16 levels were significantly higher and were predictive for monitoring inflammatory activity in patients with FMF. CXCL16 may be a promising biomarker for FMF diagnosis.

Clinical Significance of Serum Soluble TNF Receptor I/II Ratio for the Differential Diagnosis of Tumor Necrosis Factor Receptor-Associated Periodic Syndrome From Other Autoinflammatory Diseases.

Objectives: Genetic analysis of TNFRSF1A can confirm the diagnosis of tumor necrosis factor receptor-associated periodic syndrome (TRAPS), but interpretation of the pathogenesis of variants of unknown significance is sometimes required. The aim of this study was to evaluate the clinical significance of serum soluble tumor necrosis factor receptor type I (sTNFR-I)/II ratio to differentiate TRAPS from other autoinflammatory diseases. Methods: Serum sTNFR-I and sTNFR-II levels were measured using an enzyme-linked immunosorbent assay in patients with TRAPS (n = 5), familial Mediterranean fever (FMF) (n = 14), systemic juvenile idiopathic arthritis (s-JIA) (n = 90), and Kawasaki disease (KD) (n = 37) in the active and inactive phase, along with healthy controls (HCs) (n = 18). Results: In the active phase, the serum sTNFR-I/II ratio in patients with s-JIA, KD, and FMF was significantly elevated compared with that in HCs, whereas it was not elevated in patients with TRAPS. In the inactive phase, the serum sTNFR-I/II ratio in patients with s-JIA and FMF was significantly higher compared with that in HCs, and the ratio was lower in TRAPS patients than in patients with s-JIA and FMF. Conclusions: Low serum sTNFR-I/II ratio in the active and inactive phase might be useful for the differential diagnosis of TRAPS and other autoinflammatory diseases.

Clinical Features at Onset and Genetic Characterization of Pediatric and Adult Patients with TNF-α Receptor-Associated Periodic Syndrome (TRAPS): A Series of 80 Cases from the AIDA Network.

This study explores demographic, clinical, and therapeutic features of tumor necrosis factor receptor-associated periodic syndrome (TRAPS) in a cohort of 80 patients recruited from 19 Italian referral Centers. Patients' data were collected retrospectively and then analyzed according to age groups (disease onset before or after 16 years) and genotype (high penetrance (HP) and low penetrance (LP) TNFRSF1A gene variants). Pediatric- and adult-onset were reported, respectively, in 44 and 36 patients; HP and LP variants were found, respectively, in 32 and 44 cases. A positive family history for recurrent fever was reported more frequently in the pediatric group than in the adult group (p < 0.05). With reference to clinical features during attacks, pericarditis and myalgia were reported more frequently in the context of adult-onset disease than in the pediatric age (with p < 0.01 and p < 0.05, respectively), while abdominal pain was present in 84% of children and in 25% of adults (p < 0.01). Abdominal pain was significantly associated also to the presence of HP mutations (p < 0.01), while oral aphthosis was more frequently found in the LP variant group (p < 0.05). Systemic amyloidosis occurred in 25% of subjects carrying HP variants. As concerns laboratory features, HP mutations were significantly associated to higher ESR values (p < 0.01) and to the persistence of steadily elevated inflammatory markers during asymptomatic periods (p < 0.05). The presence of mutations involving a cysteine residue, abdominal pain, and lymphadenopathy during flares significantly correlated with the risk of developing amyloidosis and renal impairment. Conversely, the administration of colchicine negatively correlated to the development of pathologic proteinuria (p < 0.05). Both NSAIDs and colchicine were used as monotherapy more frequently in the LP group compared to the HP group (p < 0.01). Biologic agents were prescribed to 49 (61%) patients; R92Q subjects were more frequently on NSAIDs monotherapy than other patients (p < 0.01); nevertheless, they required biologic therapy in 53.1% of cases. At disease onset, the latest classification criteria for TRAPS were fulfilled by 64/80 (80%) patients (clinical plus genetic items) and 46/80 (57.5%) patients (clinical items only). No statistically significant differences were found in the sensitivity of the classification criteria according to age at onset and according to genotype (p < 0.05). This study describes one of the widest cohorts of TRAPS patients in the literature, suggesting that the clinical expression of this syndrome is more influenced by the penetrance of the mutation rather than by the age at onset itself. Given the high phenotypic heterogeneity of the disease, a definite diagnosis should rely on both accurate working clinical assessment and complementary genotype.

Gene-Dose Effect of MEFV Gain-of-Function Mutations Determines ex vivo Neutrophil Activation in Familial Mediterranean Fever.

Familial Mediterranean fever (FMF) is caused by mutations within the Mediterranean fever (MEFV) gene. Disease severity depends on genotype and gene dose with most serious clinical courses observed in patients with M694V homozygosity. Neutrophils are thought to play an important role in the initiation and perpetuation of inflammatory processes in FMF, but little is known about the specific characteristics of these cells in FMF patients. To further characterize neutrophilic inflammatory responses in FMF and to delineate gene-dose effects on a cellular level, we analyzed cytokine production and activation levels of isolated neutrophils derived from patients and subjects with distinct MEFV genotypes, as well as healthy and disease controls. Serum levels of interleukin-18 (IL-18) (median 11,485 pg/ml), S100A12 (median 9,726 ng/ml), and caspase-1 (median 394 pg/ml) were significantly increased in patients with homozygous M694V mutations. Spontaneous release of S100A12, caspase-1, proteinase 3, and myeloperoxidase (MPO) was restricted to ex vivo cultured neutrophils derived from patients with two pathogenic MEFV mutations. IL-18 secretion was highest in patients with two mutations but also increased in neutrophils from healthy heterozygous MEFV mutation carriers, exhibiting an ex vivo gene-dose effect, which was formerly described by us in patients' serum. CD62L (l-selectin) was spontaneously shed from the surface of ex vivo cultured neutrophils [median of geometric mean fluorescence intensity (gMFI) after 5 h: 28.8% of the initial level]. While neutrophils derived from healthy heterozygous mutation carriers again showed a gene-dose effect (median gMFI: 67.1%), healthy and disease controls had significant lower shedding rates (median gMFI: 83.6 and 82.9%, respectively). Co-culture with colchicine and/or stimulation with adenosine triphosphate (ATP) and lipopolysaccharide (LPS) led to a significant increase in receptor shedding. Neutrophils were not prevented from spontaneous shedding by blocking IL-1 or the NLRP3 inflammasome. In summary, the data demonstrate that ex vivo cultured neutrophils derived from FMF patients display a unique phenotype with spontaneous release of high amounts of IL-18, S100A12, MPO, caspase-1, and proteinase 3 and spontaneous activation as demonstrated by the loss of CD62L. Neutrophilic activation seems to be independent from IL-1 activation and displays a gene-dose effect that may be responsible for genotype-dependent phenotypes.

Can Calprotectin Show Subclinical Inflammation in Familial Mediterranean Fever Patients?

BACKGROUND: Familial Mediterranean fever (FMF) is an autoinflammatory disease that has self-limiting inflammatory attacks during polyserositis. Hepcidin is a protein, and interleukin-6 stimulation increases hepcidin levels. Calprotectin (CLP) is a recently defined cytokine released from monocytes and neutrophils in response to tissue trauma and inflammation. There are studies in the literature showing that it can be used as a biomarker in rheumatic diseases such as ankylosing spondylitis and rheumatoid arthritis. Here, we compared the levels of hepcidin and CLP in healthy individuals and FMF patients during an attack-free period and show its relation to genetic mutations. METHODS: This is a cross-sectional study. Between July 2017 and December 2017, 60 patients diagnosed with FMF an admitted to the Cumhuriyet University Faculty of Medicine Department of Internal Medicine Rheumatology as well as 60 healthy volunteers without any rheumatic, systemic, or metabolic diseases were enrolled in this study. Blood was collected from a peripheral vein to measure serum CLP and hepcidin levels. Blood tests were examined by ELISA; the study protocol was approved by the local ethics committee. RESULTS: Median serum hepcidin level was 468.1 (210.3-807.8) pg/mL in FMF group and 890.0 (495.0-1,716.9) pg/mL in the healthy control (HC) group. There was a statistically significant difference between the two groups (P < 0.001). The median serum levels of CLP in the FMF group were measured as 1,331.4 (969.3-1,584.6 pg/mL and 73.8(45.0-147.9) pg/mL in the HC group. There was a statistically significant difference between the two groups (P < 0.001). Receiver operating characteristic analysis showed that the sensitivity was 66.7% and the specificity was 71.7% at serum hepcidin < 581.25 pg/mL (P < 0.05); the sensitivity was 96.7% and specificity was 100% at CLP > 238 pg/mL (P < 0.05). There was no significant difference between serum hepcidin and CLP levels in FMF patients with M694V homozygous and M694V heterozygous (P > 0.05). There was no significant difference in serum hepcidin levels between FMF patients with and without arthritis, proteinuria, and amyloidosis (P < 0.05). There was no significant correlation between laboratory findings, gender, age, and serum CLP and hepcidin levels (P > 0.05, r < 0.25). CONCLUSION: Serum CLP levels in FMF patients during an attack-free period are significantly higher than in the HC groups. Serum hepcidin levels in FMF patients are significantly lower than in the HC group. Low levels of hepcidin may be explained by including FMF patients during an attack-free period in the study. CLP may be an important biomarker in FMF. A better understanding of the role of these biomarkers in the diagnosis of FMF is needed to evaluate the results in a more comprehensive way.

Red Cell Distribution Width (RDW) as a Marker of Subclinical Inflammation in Children with Familial Mediterranean Fever.

BACKGROUND: Familial Mediterranean fever (FMF) is an autoinflammatory disease with potentially devastating effects on the kidney, and the chronic subclinical inflammation may also be deleterious. Further, proteinuria has been associated with chronic inflammatory states. OBJECTIVE: We aimed to probe whether red cell distribution width (RDW) can be used as a reliable indicator of subclinical disease in FMF patients. METHODS: Ninety-nine children with FMF, according to the new pediatric FMF criteria, were included in the present study. All were attack-free at the time of the study. They were compared with 44 healthy age-matched controls. For all patients and controls, the following tests were done: Complete blood count (in the form of red cell count, leukocyte count, platelet count, hemoglobin, RDW and MCV), CRP, ESR, creatinine and an estimated glomerular filtration rate (e-GFR). For patients, serum and urine albumin and albumin/creatinine ratio were also determined. Group 1 consisted of 61 patients, who were not suffering from microalbuminuria, and Group 2 consisted of 38 patients who had confirmed albuminuria. RESULTS: RDW and ESR were significantly higher in patients with FMF without microalbuminuria than in controls, while MCV was smaller in controls (p<0.05). CONCLUSION: RDW can be used as an indicator of subclinical inflammation in children with FMF. The tests are easy to perform and cheaper than more sophisticated tests. Microalbuminuria may be silent and occur on the background of normal levels of acute-phase reactants. All cases must be routinely checked for microalbuminuria.

Assessment of Epicardial Adipose Tissue Thickness in Children with Familial Mediterranean Fever.

BACKGROUND: Familial Mediterranean fever (FMF) is suggested to be associated with increased risk of atherosclerosis. Epicardial adipose tissue (EAT) thickness is used in prediction of atherosclerotic risk. The aim of our study was to evaluate EAT thickness in FMF patients for early detection of risk of atherosclerosis and to be compared with its level in healthy controls. METHODS: Thirty 6- to 18-year-old children with FMF and 30 age- and sex-matched children (control group) were included in the study. Disease characteristics, disease severity and Mediterranean fever gene mutations were recorded. EAT thicknesses was measured by echocardiography. RESULTS: EAT in patients' group was significantly greater than that of controls (5.21 ± 2.3 vs. 2.81 ± 2.96 mm, p = 0.001) and was correlated with cholesterol level and platelets count (p = 0.047 and 0.018, respectively). CONCLUSION: This study concluded that EAT thickness was statistically increased in FMF patients than controls with a positive correlation with cholesterol level and platelet count. This finding suggests a higher risk for atherosclerosis in these patients. Follow-up study is needed to verify the effect of treatment of FMF on the EAT thickness. Further studies with larger number of patients following-up EAT are needed to verify this finding.

Serum amyloid A as a biomarker in differentiating attacks of familial Mediterranean fever from acute febrile infections.

OBJECTIVE: To determine the capability of serum amyloid A (SAA) in differentiating attacks of familial Mediterranean fever (FMF) from acute febrile upper respiratory tract infections. METHOD: Children diagnosed with FMF during febrile attacks were recorded as the patient group. The control group consisted of children with febrile upper respiratory tract infections. Complete blood count, serum amyloid A (SAA), C-reactive protein (CRP), and erythrocyte sedimentation rate were recorded in both groups during febrile episodes. RESULTS: The cohort consisted of 28 children with FMF attack and 28 previously healthy children with acute febrile infection. While CRP and SAA levels were elevated in both groups, elevations during FMF attacks were significantly higher in the FMF group than in the control group. Median CRP was 85 mg/L in the FMF attack group and was 36 mg/L in the control group (p = 0.001). Median SAA was 497.5 mg/L in the FMF attack group and was 131.5 mg/L in the control group (p < 0.001). Correlation analyses showed that SAA and CRP were positively correlated in the FMF attack group (r = 0.446, p = 0.01). The best cut-off value for SAA in differentiating FMF attack from an acute febrile infection was 111.5 mg/L (sensitivity 100%, specificity 65.1%, area under curve (AUC) = 0.78, confidence interval 0.66-0.90, p < 0.001). CONCLUSION: Serum amyloid A is a sensitive but not specific marker for demonstrating inflammation in FMF. SAA levels rise substantially in febrile upper respiratory tract infections.Key Points• SAA levels rise substantially in febrile upper respiratory tract infections.• SAA is a sensitive but not specific method for demonstrating inflammation.• SAA cut-off value for discriminating FMF attacks from febrile infection is 111.5 mg/L (sensitivity 100%, specificity 65.1%).

The role of endothelium-derived hyperpolarizing factor in children with familial mediterranean fever.

OBJECTIVE: Familial Mediterranean Fever is an autoinflammatory disease characterized by inflammatory attacks in serous tissues often accompanied by endothelial dysfunction. This study aimed to evaluate the effect of endothelium-derived hyperpolarizing factor, which is an indicator of endothelial dysfunction in children with familial Mediterranean fever. METHODS: This study include 57 children with familial Mediterranean fever and 31 children as healthy controls. Blood samples were collected from all participants to measure their endothelium-derived hyperpolarizing factor, complete blood count and C-reactive protein. In addition, inflammatory markers, mutation analyses, and microalbuminuria were examined only in the patient group. RESULTS: The mean age of the patient group was 9.8 ± 4.0 (2.5-18) years, while the mean age of control group was 9.5 ± 3.9 (2.5-16) years (p=0.808). Study group had significantly higher C-reactive protein levels and systolic and diastolic blood pressures and lower endothelium-derived hyperpolarizing factor values than the control group (p=0.0001, p=0.002, p=0.035 and p=0.009, respectively). CONCLUSION: Low levels of endothelium-derived hyperpolarizing factor, high levels C-reactive protein and high blood pressure in patients with familial Mediterranean fever can be attributed to the changes in the endothelium resulting from subacute inflammation.

High prolidase levels in patients with Familial Mediterranean Fever (FMF).

INTRODUCTION: Familial Mediterranean Fever (FMF) is an autoinflammatory disease. Prolidase is a specific imidodipeptidase that plays a role in collagen degradation, and an important role in inflammation and wound healing. Hypoxia-inducible factor-1α (HIF-1) is an important protein in the regulation of immunological response, hemostasis, vascularization. The aim of the study was to compare serum prolidase and HIF-1α levels in patients with FMF in attack-free period and healthy control group. METHODS: Between August 2017 and December 2017, sixty patients diagnosed with FMF according to the criteria of the Tel-hashomer and admitted to Sivas Cumhuriyet University Medical Faculty, Internal Medicine Rheumatology Department and sixty healthy volunteers were enrolled in the study. RESULTS: Median serum prolidase levels were 72.1 (25.1-114.9) ng/ml in FMF group and 30.7 (21.3-86.2) ng/mL in healthy control (HC) group (p = 0.018). ROC analysis showed that the sensitivity was 65% and the specificity was 68.3% at serum prolidase levels 54.03 ng/mL (p < 0.05). The median serum levels of HIF-1α in the FMF group was 482.0 (292.0-3967.0) pg/mL and 632.0 (362.0-927.0) pg/mL in the HC group (p > 0.05). There was no significant correlation between laboratory findings, sex, age, and prolidase (p > 0.05). CONCLUSION: Serum prolidase enzyme levels in FMF patients with attack-free period were significantly higher than in the HC group. However, the role of prolidase and HIF1-α in the FMF disease needs to be clarified with more extensive and comprehensive studies.

Update on the management of colchicine resistant Familial Mediterranean Fever (FMF).

BACKGROUND: Familial Mediterranean Fever (FMF), an autoinflammatory disease, is characterized by self-limited inflammatory attacks of fever and polyserositis along with high acute phase response. Although colchicine remains the mainstay in treatment, intolerance and resistance in a certain portion of patients have been posing a problem for physicians. MAIN BODY: Like many autoimmune and autoinflammatory diseases, many colchicine-resistant or intolerant FMF cases have been successfully treated with biologics. In addition, many studies have tested the efficacy of biologics in treating FMF manifestations. CONCLUSION: Since carriers of FMF show significantly elevated levels of serum TNF alpha, IL-1, and IL-6, FMF patients who failed colchicine were successfully treated with anti IL-1, anti IL-6, or TNF inhibitors drugs. It is best to use colchicine in combination with biologics.

Specific changes in faecal microbiota are associated with familial Mediterranean fever.

OBJECTIVES: Familial Mediterranean fever (FMF) can be complicated by AA amyloidosis (AAA), though it remains unclear why only some patients develop amyloidosis. We examined the gut microbiota composition and inflammatory markers in patients with FMF complicated or not by AAA. METHODS: We analysed the gut microbiota of 34 patients with FMF without AAA, 7 patients with FMF with AAA, 19 patients with AAA of another origin, and 26 controls using 16S ribosomal RNA gene sequencing with the Illumina MiSeq platform. Associations between bacterial taxa and clinical phenotypes were evaluated using multivariate association with linear models statistical method. Blood levels of interleukin (IL)-1ß, IL-6, tumour necrosis factor-α and adipokines were assessed by ELISA; indoleamine 2,3-dioxygenase (IDO) activity was determined by high-performance liquid chromatography. RESULTS: Compared with healthy subjects, specific changes in faecal microbiota were observed in FMF and AAA groups. Several operational taxonomic units (OTUs) were associated with FMF. Moreover, two OTUs were over-represented in FMF-related AAA compared with FMF without AAA. Additionally, higher adiponectin levels and IDO activity were observed in FMF-related AAA compared with FMF without AAA (p<0.05). CONCLUSION: The presence of specific changes in faecal microbiota in FMF and in FMF-related AAA suggests that intestinal microorganisms may play a role in the pathogenesis of these diseases. These findings may offer an opportunity to use techniques for gut microbiota manipulation.

Evaluation of analytical factors associated with targeted MEFV gene sequencing using long-range PCR/massively parallel sequencing of whole blood DNA for molecular diagnosis of Familial Mediterranean fever.

BACKGROUND: Long-range PCR (LR-PCR) is used to enrich the target regions of the genome. This study aimed to establish the pipeline of targeted gene sequencing using LR-PCR and massively parallel sequencing (MPS). METHODS: The 14-kb-long MEFV gene, including the entire coding exons, was selected as a target gene and amplified using LR-PCR. The evaluated analytical factors were as follows: LR-PCR conditions, three types of post-PCR cleanup methods, and two types of MPS library preparation methods. RESULTS: With regard to LR-PCR conditions, Tks Gflex DNA polymerase at 7-min (30-s/kb) annealing/extension with 100-ng genomic DNA input had the highest yield. Regarding post-PCR purification methods, the magnetic beads-based method had high recovery and purity. In the MPS library preparation methods, the ligation-based method had a higher base coverage in the target (94.58%), uniformity of base coverage (99.95%), and target bases with no strand bias (97.40%). The exonic variants determined by Sanger sequencing were detected by both ligation- and transposon-based methods. CONCLUSIONS: Various analytical factors were evaluated, and the pipeline of targeted gene sequencing using LR-PCR and MPS was established. These data can enable the optimization of targeted gene sequencing using LR-PCR and MPS in the clinical laboratory.

Assessment of Mean Platelet Volume in Patients with AA Amyloidosis and AA Amyloidosis Secondary to Familial Mediterranean Fever: A Retrospective Chart - Review Study.

BACKGROUND Amyloidosis is a protein-misfolding disease characterized by the deposition of aggregated proteins in the form of abnormal fibrils that disrupt tissue structure, ultimately causing disease. Amyloidosis is very frequent in untreated familial Mediterranean fever (FMF) patients and it is the most important feature that determines the prognosis of FMF disease. The mean platelet volume (MPV) in FMF has been previously studied. However, whether MPV level in FMF patients is lower or higher compared to healthy controls remains a topic of ongoing debate. In this study, we aimed to investigate MPV values and to assess the correlation between MPV and proteinuria in patients with AA amyloidosis and AA amyloidosis secondary to familial Mediterranean fever (AA-FMF) through a retrospective chart-review. MATERIAL AND METHODS This study was carried out on 27 patients with AA amyloidosis, 36 patients with AA amyloidosis secondary to FMF (a total of 63 patients with AA), and 29 healthy controls. There was no statistically significant difference between the AA patients and the control group (p=0.06) or between the AA-FMF group and the control group in terms of MPV values (p=0.12). RESULTS We found a statistically significant negative correlation between MPV and thrombocyte count in all groups (p<0.05 for all groups), but there was no correlation between MPV and proteinuria levels in AA patients (p=0.091). CONCLUSIONS While similar results also exist, these findings are contrary to the majority of previous studies. Therefore, further controlled clinical prospective trials are necessary to address this inconsistency.

[Validation of the usual values provided by a supplier without access to a control population: example of serum amyloid A]. / Validation des valeurs usuelles proposées par un fournisseur sans accès à une population témoin : exemple de la sérum amyloïde A.

As part of the laboratory accreditation process, it may be required to determine the laboratory's own reference values. Thus, we have accredited in our laboratory, the serum amyloid A (SAA) assay for which the supplier gave the usual values. However, we did not have a reference population to check them. MATERIALS AND METHODS: We extracted from our laboratory information management system, the values of all SAA and C-reactive protein (CRP) assays performed simultaneously from 2014 to 2018. We selected all SAA-CRP couples with a CRP <5 mg/L and <3 mg/L assuming that these subjects were comparable to the general population. For each of the selected CRP thresholds, we quantified the number of subjects with SAA ≤6.4 mg/L (provider's data), then SAA ≤10 mg/L (threshold below which the risk of kidney complications is low). We compared annual averages of SAA-CRP couples (2014-2018) by analysis of variance (ANOVA). RESULTS AND DISCUSSION: For subjects with CRP <5 mg/L, we found SAA value ≤6.4 mg/L in 84.6% and ≤10 mg/L in 92.8% of cases. These results were respectively 89.6% et 95.6% when considering CRP <3 mg/L. Similar thresholds were observed for adults and children. The ANOVA analysis did not show any difference per year from 2014 to 2018 for both SAA and CRP in children, adults and the total population. CONCLUSION: Our reference values were comparable to those given in the supplier's record and those issued from the literature both for children and adults. The analysis of the evolution of the biomarker average level as a function of time could be an additional relevant element.