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Featured researches published by Merav Lidar.


Seminars in Arthritis and Rheumatism | 2004

Colchicine nonresponsiveness in familial mediterranean fever: clinical, genetic, pharmacokinetic, and socioeconomic characterization

Merav Lidar; Jean-Michel Scherrmann; Yael Shinar; Angela Chetrit; Elisabeth Niel; Ruth Gershoni-Baruch; Pnina Langevitz; Avi Livneh

OBJECTIVES To identify the ethnic, clinical, genetic, and pharmacokinetic correlates of colchicine treatment failure in patients with familial Mediterranean fever (FMF). METHODS Fifty-nine FMF patients, unresponsive to a daily dose of > or =2 mg colchicine, were compared with 51 colchicine-responsive patients by clinical, demographic, and socioeconomic assessment, FMF gene (MEditerranean FeVer [MEFV]) mutation and serum amyloid A1 (SAA1) gene polymorphism analysis, and plasma and white blood cell colchicine level determination. RESULTS Colchicine responders and nonresponders were comparable with respect to gender, age, duration and onset of the disease, and various demographic parameters. The 2 cohorts were found to carry mainly the M694V MEFV mutation and had a similar number of homozygotes or compound heterozygotes. Predominance of the alpha/beta alleles of SAA1 and comparable plasma and polymorphonuclear colchicine concentrations characterized both groups. Nonresponders were from lower socioeconomic backgrounds, had less education, and a more severe form of disease. A statistically significant 2-fold elevation of colchicine concentration in the mononuclear cells (MNC) of responders was found. CONCLUSIONS Colchicine treatment failure in FMF is associated with inadequate colchicine MNC concentration, probably resulting from a genetic defect unrelated to the underlying FMF.


Diabetes Research and Clinical Practice | 2000

Considerations about the threshold value of microalbuminuria in patients with diabetes mellitus: lessons from an 8-year follow-up study of 599 patients

Rita Rachmani; Zohar Levi; Merav Lidar; Inna Slavachevski; Elizabeth Half-Onn; Mordchai Ravid

OBJECTIVE To examine the validity of the time honored threshold value for microalbuminuria of 30 mg/24 h, by analyzing an 8-year follow-up data of 599 patients with diabetes mellitus type 2, normal blood pressure and base-line albumin excretion rate (AER) </=30 mg/24 h. PATIENTS The patients were allocated to three groups according to the baseline values of AER. Group I: 0-10 mg/24 h; Group II: 10.1-20 mg/24 h; Group III: 20.1-30 mg/24 h. RESULTS Progression to microalbuminuria during follow-up occurred in 25.3, 47.3 and 85.3% of the patients in Group I, II and III, respectively. Compared to Group I, the risk to progress to microalbuminuria was 2. 34 (95% CI 1.32-4.43, P=0.029) in patients of Group II and 12.36 (95% CI 8.9-16.5, P=0.0001) in Group III. The average annual decline in glomerular filtration rate (GFR) was 1.19, 1.64 and 2.52 ml/min per year, respectively in the three groups. The correlation between baseline AER values and subsequent decline in GFR was exponential without a clear threshold value. Compared to Group I, the odds ratio for any cardiovascular end point (e.g. death, non-fatal myocardial infarction etc.) was 1.9 (95% CI 0.8-2.5, P=0.22) for patients of Group II and 9.8 (95% CI 6.7-12.3, P=0.001) for Group III. CONCLUSIONS The present study shows that patients with baseline AER values of 20.1-30 mg/24 h show an accelerated decline in GFR and significantly higher risk for cardiovascular events than patients with AER values below 20 mg/24 h. Though AER is obviously a continuous variable, the arbitrary threshold value for screening and for preventive strategies should probably be set at 20 rather than at 30 mg/24 h.


Israel Medical Association Journal | 2009

The Role of Infection in Inflammatory Bowel Disease: Initiation, Exacerbation and Protection

Merav Lidar; Pnina Langevitz; Yehuda Shoenfeld

Inflammatory bowel disease, a collective term for ulcerative colitis and Crohns disease, is a chronic, immune-mediated disease of the gastrointestinal tract that develops in genetically susceptible individuals. The role of infection in the development of inflammatory bowel disease is underscored by various clinical observations, such as the delayed age of onset, suggesting that childhood exposure to pathogens is essential, and the clinical improvement that follows decreasing bacterial intestinal load. Over the years, many a pathogen has been linked to the development and exacerbation of inflammatory bowel disease, notably; Mycobacterium paratuberculosis, Escherichia coli, Listeria monocytogenes and Chlamydia as well as viruses such as measles, mumps, rubella, Epstein-Barr virus and cytomegalovirus. Presently, leading theories of disease pathogenesis suggest loss of immune tolerance to normal commensal bacteria coupled with excessive exposure to bacterial antigenic products. This review describes the most commonly implicated pathogens in the causation of IBD and presents the evidence supporting their pathogenic role as well as data that offset their importance.


Autoimmunity | 2009

The infectious etiology of vasculitis.

Merav Lidar; Noga Lipschitz; Pnina Langevitz; Yehuda Shoenfeld

Infectious agents have been implicated in the etiopathogenesis of various vasculitides via numerous and overlapping mechanisms including direct microbial invasion of endothelial cells, immune complex mediated vessel wall damage and stimulation of autoreactive B and/or T cells through molecular mimicry and superantigens. While the causative role of hepatitis B virus in polyarteritis nodosa and hepatitis C virus in mixed cryoglobulinemia is clearly established, evidence for the association of other infectious agents with vasculitis, including human immunodeficiency virus, parvovirus B19, cytomegalovirus, varicella zoster virus, Staphylococcus aureus, rickettsiaceae, Treponema pallidum and Borrelia burgdorferi, among numerous others, is accumulating. The spectrum of association of infectious agents; bacteria, viruses and parasites, with systemic vasculitides, will be reviewed herewith.


Annals of the New York Academy of Sciences | 2009

Infectious serologies and autoantibodies in inflammatory bowel disease: insinuations at a true pathogenic role.

Merav Lidar; Pnina Langevitz; Ori Barzilai; Maya Ram; Bat-Sheba Porat-Katz; Nicola Bizzaro; Elio Tonutti; R. Maieron; Yehuda Chowers; Simon Bar-Meir; Yehuda Shoenfeld

The aim of this study was to reevaluate the role of infection in inflammatory bowel disease (IBD). Sera from 119 patients with IBD [80 with Crohns disease (CD); 39 with ulcerative colitis] and 98 healthy controls were assessed using the Bio‐Rad BioPlex 2200 for the presence of Toxoplasma gondii, cytomegalovirus, Epstein–Barr virus, Treponema pallidum, and Saccharomyces cerevisiae. Hepatitis B virus, hepatitis C virus (HCV), and anti‐Helicobacter pylori antibodies were assessed by ELISA. In addition, sera were tested for a panel of antibodies associated with thrombophilia as well as various autoantibodies. Titers of antibodies toward HCV and T. gondii, and S. cerevisiae were higher in IBD patients than in controls, while the H. pylori autoantibodies were less prevalent among the patient population. Several thrombophilia‐associated antibodies were more common in CD patients, and a single patient had a thromboembolic event. Our results show an excess of anti‐HCV and anti‐T. gondii antibodies among patients with IBD compared to healthy controls. Whereas the former may be the result of immunosuppression from the inflammatory disease itself or from the medications used to treat it, the latter association suggests that T. gondii is involved in the etiopathogenesis of IBD, and especially CD, in humans, as has been shown in the murine model. However, our findings also reiterate the positive association between CD and anti‐S. cerevisiae antibodies as well as the negative association with H. pylori infections. These, in turn, lend indirect support to the “hygiene hypothesis” in IBD as well as the newly proposed role of commensal bacteria in the initiation of the disease process.


Medicine | 2002

CROHN DISEASE IN PATIENTS WITH FAMILIAL MEDITERRANEAN FEVER

Herma Fidder; Yehuda Chowers; Merav Lidar; Matan Sternberg; Pnina Langevitz; Avi Livneh

Crohn disease and familial Mediterranean fever (FMF) are inflammatory diseases characterized by abdominal pain and fever. The concurrence of the 2 diseases (FMF-CD) may pose a challenge to diagnosis and treatment. We undertook the present study to determine the prevalence of Crohn disease in FMF and to characterize FMF-CD patients clinically and genetically. Using a computerized search, the patients of our FMF clinic were screened for a concomitant diagnosis of Crohn disease. Patients and their medical records were thoroughly examined, and their DNA was genotyped for mutations in the MEFV gene. Control groups of ethnically and sex-matched patients suffering from each of the diseases alone, either Crohn disease or FMF, were used for comparison. We identified 7 patients with concomitant Crohn disease and FMF, which is more than the expected prevalence in the general population (p = 0.03). Crohn disease presented at a significantly later age in the FMF-CD group (40.6 ± 10.0 yr versus 26.2 ± 11.4 yr; p < 0.004). Disease severity and other characteristics of Crohn disease were comparable to the Crohn disease control group. Contrary to the FMF control group patients, FMF in FMF-CD patients was characterized by a higher attack frequency (p < 0.05) and increased prevalence of amyloidosis (p < 0.02). The overall severity score was similar in both groups. In conclusion, Crohn disease appears to be more prevalent in FMF and presents later than in patients without FMF. FMF in this group of patients shows a higher attack frequency and is more often complicated by amyloidosis.


The Journal of Pediatrics | 2010

Familial Mediterranean Fever in the First Two Years of Life: A Unique Phenotype of Disease in Evolution

Shai Padeh; Avi Livneh; Elon Pras; Yael Shinar; Merav Lidar; Olga Feld; Yackov Berkun

OBJECTIVE To characterize the clinical and genetic features of familial Mediterranean fever (FMF). STUDY DESIGN Clinical presentation and MEditerranean FeVer mutation type of all patients with FMF, who first manifested the disease at < or =2 years of age were analyzed and compared with patients who first presented with FMF between 2 and 16 years. RESULTS Of 814 patients with FMF, in 254 patients (31.2%) the first FMF attack was at < or =2 years of age, with a mean age at onset of 1.1 +/- 0.8 years. They were compared with 242 patients who presented with their first manifestation of FMF at 2 to 16 years. The clinical manifestations of FMF were comparable in the 2 patient groups, but the delay of diagnosis was longer in patients with early presentation (3.2 +/- 3.2 years vs.1.9 +/- 2.7 years in the group with onset at 2-16 years, P < .001). A subgroup of patients (60/254), who were diagnosed at < or =2 years had the highest rate of attacks of fever alone as their sole manifestation (40.0% vs 8.4%, P < .05), and less peritonitis (45% vs 86.1%, P < .05) and pleuritis (3.4% vs 32.9%, P < .05). Most of these patients were homozygous for the M694V mutation and were of North African (Sephardic Jewish) extraction. CONCLUSION In early life, FMF often begins with an atypical presentation, characterized by attacks of fever alone, and its diagnosis and initiation of treatment is therefore significantly delayed.


Autoimmunity Reviews | 2012

Incomplete response to colchicine in M694V homozygote FMF patients

Merav Lidar; Hagith Yonath; Naama Shechter; Fabienne Sikron; Siegal Sadetzki; Pnina Langevitz; Avi Livneh; Elon Pras

BACKGROUND Previous studies have shown that with prophylactic colchicine 65% of the patients suffering from Familial Mediterranean fever (FMF) will show a complete response, 30% a partial response and about 5% will show minimum or no response. These studies were performed before the isolation of the disease gene. Genotyping enables us to study the response rates according to specific mutations. We have witnessed a large number of M694V homozygotes who do not respond well to colchicine despite being treated with maximal sustained doses. AIM To assess the response rates to colchicine in M694V homozygote FMF patients in comparison to other prevalent genotypes. METHODS We conducted a telephonic survey which included 112 FMF patients: 40 M694V homozygotes, and 2 comparison groups of 41 M694V/V726A compound heterozygotes and 31 V726A homozygotes. The questionnaire included demographic, social and clinical features, colchicine dose, response rates and reported side effects. RESULTS M694 homozygotes showed a more severe disease, and were treated with higher doses of colchicine (average dose 1.98±0.56 compared to 1.47±0.58, p=0.0001 and 1.13±0.41, p<0.001 in the M694V/V726A compound heterozygotes and the V726A homozygotes, respectively); Colchicine related side effects were noted in 40% of the M694V homozygotes. The average rate of attacks in treated M694V homozygotes (0.70±1.06) was higher compared to the two other groups (0.14±0.26, p=0.002 and 0.08±0.20, p=0.0009, respectively) and only 25% of them reported no attacks in the last year. None of the patients who took part in this study had amyloidosis. Side effects limiting the dose of colchicine were noted in 40% of the M694V homozygotes. CONCLUSIONS Despite receiving higher doses of colchicine the prevalence of complete responders among M694V homozygotes is much lower than previously appreciated. The results highlight the need for additional treatment modalities for these patients.


Seminars in Arthritis and Rheumatism | 2011

The familial Mediterranean fever gene as a modifier of periodic fever, aphthous stomatitis, pharyngitis, and adenopathy syndrome.

Yackov Berkun; Ran Levy; Adam Hurwitz; Merav Lidar; Avi Livneh; Shai Padeh

OBJECTIVE Periodic fever, aphthous stomatitis, pharyngitis, and adenopathy (PFAPA) syndrome is a sporadic disease, characterized by periodic attacks of inflammation. Mutations in the MEFV, the gene associated with familial Mediterranean fever (FMF), may lead to subclinical inflammation in asymptomatic carriers and modify the phenotype of some inflammatory diseases. We aimed at investigating the effect of MEFV gene mutations on disease phenotype in PFAPA. PATIENTS AND METHODS The cohort of this ongoing prospective study consisted of 124 children with PFAPA syndrome, followed in a single referral center, who were tested for MEFV mutations. Demographic data, clinical characteristics, and disease course of 65 PFAPA patients with and 59 without MEFV mutations (M+ and M-, respectively) were compared. RESULTS PFAPA attacks in carriers of MEFV mutations were shorter compared with patients without mutations (3.8 ± 1.7 versus 4.8 ± 1.9 days, P < 0.01). The difference was more pronounced in those carrying the M694V mutation. In M+ patients, the rates of patients with regularity of their attacks (49.2%) and oral aphthae (24.6%) were lower, compared with M- patients (74.5% and 43.9%, respectively, P < 0.05 for each of the 2 comparisons). M+ patients needed a lower corticosteroid (beclomethasone) dose to abort the attacks (0.16 ± 0.07mg/kg versus 0.19 ± 0.08, P = 0.028). No differences were observed in all other clinical and laboratory parameters, over a follow-up period of 4.3 years. CONCLUSION In PFAPA, MEFV is a modifier gene associated with an attenuated disease severity.


Annals of the New York Academy of Sciences | 2009

Infectious Serologies and Autoantibodies in Wegener's Granulomatosis and Other Vasculitides: Novel Associations Disclosed Using the Rad BioPlex 2200

Merav Lidar; Noga Lipschitz; Pnina Langevitz; Ori Barzilai; Maya Ram; Bat-Sheba Porat-Katz; Christian Pagnoux; P. Guilpain; Renato Alberto Sinico; Antonella Radice; Nicola Bizzaro; Jan Damoiseaux; Jan Willem Cohen Tervaert; Javier Martin; Loïc Guillevin; Stefano Bombardieri; Yehuda Shoenfeld

In this study we assess the presence of antibodies against infectious agents as well as for a variety of autoantibodies in an attempt to establish associations between various vasculitides and infections in order to shed light on the etiopathogenesis of these diseases and perhaps implicate a potential cure. Sera from patients with Wegeners granulomatosis (WG), polyarteritis nodosa, microscopic polyangiitis, Churg Strauss, and giant cell arteritis were compared to healthy control sera. Serum samples were assessed, using the Bio‐Rad BioPlex 2200, for the presence of Toxoplama gondii, cytomegalovirus (CMV), Epstein–Barr virus (EBV), Treponema pallidum, and Saccharomyces cerevisiae. Hepatitis B virus (HBV), hepatitis C virus (HCV), and anti‐Helicobacter pylori antibodies were assessed by ELISA. In addition, sera were tested for a panel of antibodies associated with thrombophilia as well as various autoantibodies. The prevalence of antibodies toward HCV and H. pylori was significantly higher among patients with WG. IgG antibodies toward T. gondii and IgM antibodies toward CMV were significantly more common among WG patients than among controls. WG patients exhibited more antibodies toward EBV viral capsid antigen IgG and EBV early antigen IgG compared to sera from healthy controls. In WG, positive associations were disclosed between CMV IgG antibodies and the presence of gastrointestinal manifestations and renal involvement, and there was a higher Birmingham vasculitis activity score in association with elevated titers of EBV viral capsid antigen IgG antibodies. Otorhinolaryngeal manifestations were more common in those with positive IgG antibodies for EBV early antigen. Our results unveil novel associations between WG and various infectious agents, including HCV, H. pylori, T. gondii, CMV, and EBV. In addition to putative roles in initiation and exacerbation of the vasculitic process, it seems that these infectious agents also modulate the clinical phenotype of the disease.

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