Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Silvia C. Pedreira is active.

Publication


Featured researches published by Silvia C. Pedreira.


European Journal of Gastroenterology & Hepatology | 1996

Gynaecological and obstetric disorders in coeliac disease: frequent clinical onset during pregnancy or the puerperium.

Edgardo Smecuol; Eduardo Mauriño; Horacio Vázquez; Silvia C. Pedreira; Sonia Niveloni; Roberto M. Mazure; Luis A. Boerr; Julio C. Bai

Background and aim While gynaecological and obstetric disorders have been reported among women with coeliac sprue, their true prevalence and relationship to the coeliac disease process has not been completely elucidated. Our aims were to determine: (1) the prevalence of gynaecological and obstetric problems in patients with coeliac disease and the influence of strict gluten restriction on their occurrence, (2) the effect of pregnancy on the clinical course of coeliac disease and (3) the clinical features of those patients with onset of coeliac disease during pregnancy and the puerperium. Patients and methods The gynaecological and obstetric history of 130 coeliac patients and 130 age-matched healthy female controls were compared in a case-control study. Results In comparison to the controls, untreated coeliac disease patients exhibited significantly later menarche, an earlier menopause, an increased prevalence of secondary amenorrhoea and a greater incidence of spontaneous abortions. Patients who had adhered, in the long term, to a gluten-free diet had gynaecological and obstetric history indistinguishable from controls. Clinical deterioration of coeliac disease was observed in untreated patients during 17% of their pregnancies. In 14% of those untreated patients who were pregnant symptoms related to coeliac disease were manifested for the first time during either pregnancy (n = 7) or the puerperium (n = 4). Nine of these patients had underestimated features suggestive of coeliac disease. Conclusion The early diagnosis and treatment of coeliac disease may avoid significant gynaecological and obstetric complications in affected women. Celiac sprue must always be borne in mind among patients who develop diarrhoea and weight loss during pregnancy and/or the puerperium.


Clinical Gastroenterology and Hepatology | 2004

Stratification of Bone Fracture Risk in Patients With Celiac Disease

María Laura Moreno; Horacio Vazquez; Roberto Mazure; Edgardo Smecuol; Sonia Niveloni; Silvia C. Pedreira; Emilia Sugai; Eduardo Mauriño; Juan C. Gomez; Julio C. Bai

BACKGROUND AND AIMS Our objective in this cross-sectional, case-control study was to gain insight into celiac osteopathy by examining a well-defined cohort of patients with a wide clinical spectrum of the disease. METHODS We studied 148 unselected celiac patients and 296 (1:2) age- and sex-matched controls diagnosed with functional gastrointestinal disorders. Based on the clinical history, 53% were classically symptomatic, 36% had subclinical celiac disease, and 11% were silent, detected by screening. The fracture information was obtained through an in-person interview using a pre-designed questionnaire. RESULTS Classically symptomatic patients had an increased number of fractures in the peripheral skeleton (47%) compared with age- and sex-matched controls (15%; odds ratio, 5.2; 95% confidence interval, 2.8-9.8). However, fractures in subclinical/silent celiac cases (20%) were no different from those in controls (14%; odds ratio, 1.7, 0.7-4.4). Compared with the subclinical/silent group, a significantly greater prevalence of fractures was detected in classically symptomatic patients (odds ratio, 3.6, 1.7-7.5). Compared with controls, celiac disease patients had significantly more fractures produced by mild trauma (P < 0.01), but there were no differences in the severity of trauma events that induced fractures. Mean bone density femoral neck z score was higher for subclinical/silent cases compared with classically symptomatic patients (P < 0.05). CONCLUSIONS Celiac patients show a very wide variation in fracture risk, with increased risk in classically symptomatic patients. Diagnostic and therapeutic strategies to prevent bone loss and fracture should be preferentially used in the subgroup of patients with classic clinical disease.


Clinical Gastroenterology and Hepatology | 2005

Permeability, zonulin production, and enteropathy in dermatitis herpetiformis

Edgardo Smecuol; Emilia Sugai; Sonia Niveloni; Horacio Vázquez; Silvia C. Pedreira; Roberto M. Mazure; María Laura Moreno; Marcelo Label; Eduardo Mauriño; Alessio Fasano; Jon Meddings; Julio C. Bai

BACKGROUND & AIMS Dermatitis herpetiformis (DH) is characterized by variable degrees of enteropathy and increased intestinal permeability. Zonulin, a regulator of tight junctions, seems to play a key role in the altered intestinal permeability that characterizes the early phase of celiac disease. Our aim was to assess both intestinal permeability and serum zonulin levels in a group of patients with DH having variable grades of enteropathy. METHODS We studied 18 DH patients diagnosed on the basis of characteristic immunoglobulin (Ig)A granular deposits in the dermal papillae of noninvolved skin. Results were compared with those of classic celiac patients, patients with linear IgA dermatosis, and healthy controls. RESULTS According to Marshs classification, 5 patients had no evidence of enteropathy (type 0), 4 patients had type II, 2 patients had type IIIb damage, and 7 patients had a more severe lesion (type IIIc). Intestinal permeability (lactulose/mannitol ratio [lac/man]) was abnormal in all patients with DH. Patients with more severe enteropathy had significantly greater permeability ( P < .05). The serum zonulin concentration (enzyme-linked immunosorbent assay) for patients with DH was 2.1 +/- .3 ng/mg with 14 of 16 (87.5%) patients having abnormally increased values. In contrast, patients with linear IgA dermatosis had normal histology, normal intestinal permeability, and negative celiac serology. CONCLUSIONS Increased intestinal permeability and zonulin up-regulation are common and concomitant findings among patients with DH, likely involved in pathogenesis. Increased permeability can be observed even in patients with no evidence of histologic damage in biopsy specimens. Patients with linear IgA dermatosis appear to be a distinct population with no evidence of gluten sensitivity.


Gastroenterology | 1998

Successful treatment of retractile mesenteritis with oral progesterone

Roberto M. Mazure; Pablo Fernández Marty; Sonia Niveloni; Silvia C. Pedreira; Horacio Vázquez; Edgardo Smecuol; Zulema Kogan; Luis A. Boerr; Eduardo Mauriño; Julio C. Bai

Retractile mesenteritis is a rare inflammatory mesenteric disorder that involves the intestine secondarily. The natural history of this process is diverse, but most patients require some empiric therapeutic measures. Up to now, pharmacological therapy has included corticosteroids, colchicine, and immunosuppressive drugs. Although these drugs are successful in most patients, some have been refractory to these therapies and, in others, the beneficial effects were counterbalanced by adverse reactions. Many patients require surgery, but most have poor results. This report describes a 42-year-old man with histologically proven retractile mesenteritis refractory to surgical intervention who had a good response to oral progesterone (10 mg/day for 6 months) with complete disappearance of tumor mass and clinical symptoms. No adverse effects were detected. Current knowledge about the mechanism by which progesterone affects fibrogenesis is scanty. It seems likely that progesterone down-regulates proliferation and metabolism of fibroblasts and fibrogenesis.


The American Journal of Gastroenterology | 2002

Azathioprine in refractory sprue: results from a prospective, open-label study

Eduardo Mauriño; Sonia Niveloni; Alejandra Claudia Cherñavsky; Silvia C. Pedreira; Roberto M. Mazure; Horacio Vázquez; Hugo Reyes; Alcira Fiorini; Edgardo Smecuol; Ana Cabanne; Monica Capucchio; Zulema Kogan; Julio C. Bai

OBJECTIVE:Refractory sprue is a rare and severe malabsorptive disorder that mimics celiac disease but is refractory to a gluten-free diet and is without initial evidence of overt lymphoma. Treatment is largely empiric and often ineffective, with steroids and immunosuppression being the mainstream therapeutic options. The aim of this study was to evaluate prospectively the effect of azathioprine on a group of patients diagnosed with refractory sprue.METHODS:We studied seven consecutive patients (five women and two men) with a well-defined diagnosis of refractory sprue and a lack of response to oral or parenteral steroids. At diagnosis, five patients had endoscopic evidence of ulcerative jejunitis, and five underwent exploratory laparotomy for exclusion of malignancies. The characteristic monoclonal TCRγ gene rearrangement was shown in five of six patients studied. Patients were treated for a mean of 11 months (range 8–12 months), and clinical, biochemical, molecular, and histological parameters were reassessed at the end of the trial. The study was a prospective, open-label, non-placebo-controlled study using azathioprine (2 mg/kg/day) plus oral prednisone (1 mg/kg/day). A gluten-free diet (n = 7) as well as enteral (n = 6) and parenteral nutrition (n = 5) were administered during the trial.RESULTS:After treatment, five patients had a complete clinical remission, and biochemical and nutritional parameters were significantly improved. Steroids were tapered after the onset of azathioprine, and no patient was on steroids at the end of the trial. Intestinal histology improved significantly in all cases (normal histology in three cases and minor infiltration in the lamina propria in two). Two patients did not respond to treatment at any time and died in months 10 and 9, of an irreversible ventricular fibrillation and sepsis, respectively. No overt lymphoma was demonstrated during the follow-up.CONCLUSIONS:The present study confirms earlier anecdotal reports on the efficacy of azathioprine in refractory sprue, with clear clinical and histological improvement shown in most patients. However, monoclonality persisted after treatment. We consider that a larger number of patients should be evaluated before a definitive recommendation is adopted for use of this drug in refractory sprue.


The American Journal of Gastroenterology | 2000

Tissue transglutaminase antibodies in celiac disease: assessment of a commercial kit

Emilia Sugai; Gisella Selvaggio; Horacio Vazquez; Martı́n Viola; Roberto Mazure; Bibiana Pizarro; Edgardo Smecuol; Daniel Flores; Silvia C. Pedreira; Eduardo Mauriño; Juan C. Gomez; Julio C. Bai

OBJECTIVE:Tissue transglutaminase was identified as the autoantigen eliciting endomysial antibody. A homemade enzyme-linked immunosorbent assay (ELISA)-based test was recently developed to determine quantitative titers of IgA antitissue transglutaminase antibody. Our objective in this study was to assess the suitability of a newly developed commercial kit for quantitative determination of antibody in patients with untreated celiac disease.MATERIALS:We tested serum samples from 79 untreated celiac patients, 42 healthy blood donors, and 18 patients with nonceliac intestinal disorders evaluated in two different centers. Samples were tested for antitissue transglutaminase, and antiendomysial and antigliadin antibodies in the center where diagnosis was performed. To assess interlaboratory variability of methods, 24 samples randomly selected were blindly tested in both centers. Antitissue transglutaminase antibodies were determined using a commercial kit (INOVA Diagnostics, Inc., San Diego, CA).RESULTS:Untreated celiac patients had significantly higher titers of antitissue transglutaminase than healthy and disease controls (p < 0.00001). According to the cut-off provided by the manufacturers (20 AU/mL), overall sensitivity was 92% (85% for one center and 100% for the other) and specificity was 98% (100% and 95%, respectively). Antiendomysial antibody was 86% sensitive and 100% specific. Discordance between antitissue transglutaminase and antiendomysial antibodies was detected in 13% of patients. Although two antitissue transglutaminase-negative cases had a positive antiendomysial antibody, the inverse situation was found in eight cases. A blind determination of antitissue transglutaminase on the same samples evidenced a good agreement (κ statistic: 0.66) between both centers when assessment was qualitative (based on the decision of positive or negative). Although correlation of titers for both determinations was highly significant (r: 0.902, p < 0.00001), a very wide interlaboratory variability (median: 50%) was detected when absolute values were considered.CONCLUSIONS:The quantitative determination of antitissue transglutaminase using a commercial kit was highly sensitive and specific for detection of celiac disease. We observed an incomplete overlapping with antiendomysial antibody. The very high variability of values between laboratories still remains to be solved so as to propose the commercial ELISA assay for the screening of celiac disease.


Journal of Clinical Immunology | 2002

Bone-specific antibodies in sera from patients with celiac disease: characterization and implications in osteoporosis.

Emilia Sugai; Alejandra Claudia Cherñavsky; Silvia C. Pedreira; Edgardo Smecuol; Horacio Vazquez; Sonia Niveloni; Roberto Mazure; Eduardo Mauriño; Gabriel A. Rabinovich; Julio C. Bai

Osteopenia and osteoporosis are well-known complications detected in celiac disease patients with still obscure pathogenesis. In the present study we investigated the presence of circulating anti-bone autoantibodies in patients with celiac disease and explored their role in the associated bone disease. We evaluated serum samples from 33 patients at the time of diagnosis and from 20 of them after treatment. Sera from patients with inflammatory bowel disease (n = 9), nonceliac osteoporotic (n = 18), and healthy individuals (n = 10) were used as controls. The presence of IgA specific anti-bone antibodies was first investigated using indirect immunofluorescence on cryosections of fetal rat tibia (20-day pregnancy). Furthermore, samples were homogenized and total tissue extracts were subjected to Western blot analysis to confirm immunoreactivity. At diagnosis, sera from 51.5% (17/33) of celiac patients had antibodies that recognized antigenic structures in chondrocytes and the extracellular matrix along mature cartilage, bone interface, and perichondrium of fetal rat bone. Among controls, only two osteoporotic patients showed very low titles of anti-bone autoantibodies. The immunostaining was localized in areas where an active mineralization process occurred and was similar to the distribution of the native bone tissue transglutaminase. The frequency of patients with positive baseline titers of anti-bone antibodies diminished significantly after treatment (P = 0.048). Western blot assays confirmed the presence of autoantibodies in sera from patients with a positive immunofluorescence staining. Autoantibodies recognized a major protein band on tissue extracts with a molecular weight of 77–80 kDa, which could be displaced when sera were preadsorbed with human recombinant tissue transglutaminase. We provide original evidence that patients with celiac disease have IgA-type circulating autoantibodies against intra- and extracellular structures of fetal rat tibia. Our findings suggest that these antibodies recognize bone tissue transglutaminase as the autoantigen, and based on the localization of the immunoreactivity we speculate that they might have an active role in the pathophysiology of celiac disease-associated bone complications.


The American Journal of Gastroenterology | 1999

Characterization of gastric mucosal lesions in patients with celiac disease: a prospective controlled study

Adriana Diamanti; Claudio Maino; Sonia Niveloni; Silvia C. Pedreira; Horacio Vazquez; Edgardo Smecuol; Alcira Fiorini; Ana Cabanne; Marı́a A Bartellini; Zulema Kogan; Jorge Valero; Eduardo Mauriño; Julio C. Bai

Objective:Several studies have demonstrated that chronic exposure to gluten may damage the structure and function of the gastric mucosa in gluten-sensitive patients. However, until now, these abnormalities have been incompletely studied. Our purpose in the present study was to characterize, in a prospective controlled study, the endoscopic and histological appearance of the gastric mucosa in a large cohort of patients with celiac disease with and without Helicobacter pylori (H. pylori) infection.Methods:We evaluated biopsy specimens taken from the gastric body and antrum of 218 individuals who underwent upper endoscopy for small bowel biopsy. One hundred-four patients had celiac disease (80 of them at the time of diagnosis-untreated). In 114 subjects celiac disease was excluded.Results:Endoscopic findings did not show a difference between the groups. The prevalence of cases with normal gastric mucosa, chronic superficial gastritis, and atrophic gastritis was similar in patients and controls. Similarly, presence of metaplasia, inflammatory activity, and lymphoid follicles and aggregates did not show differences between the groups. Histological or serological evidence of H. pylori infection was detected in 86% of patients (82% of untreated celiacs and 95% of those on those taking treatment). The infection was highly prevalent in patients (89%) and controls (97%) diagnosed with chronic gastritis. Untreated patients had a significant greater IEL count in the antrum and corpus than controls (p < 0.0001 and p < 0.001, respectively). A global analysis of the data on intraepithelial lymphocyte (IEL) counts in the different populations suggest that the inflammatory state may represent the cumulative effect of H. pylori infection and gluten sensitivity. Only three patients had IEL infiltration compatible with diagnosis of lymphocytic gastritis (count >25%) and three other patients had borderline counts.Conclusions:According to our results, celiac disease patients presented a similar prevalence of gastric mucosal abnormalities compared with the control population. Evidence of H. pylori infection was very high compared with the prevalence in the general Argentine population. As a particular observation in our celiac population, the disease was rarely associated with lymphocytic gastritis. We suggest that the chronic inflammatory state evidenced by a gastric mucosal lymphocyte infiltration may be secondary to the combination of H. pylori infection and chronic gluten ingestion in gluten-sensitive subjects.


World Journal of Gastroenterology | 2011

Risk of fracture in celiac disease: Gender, dietary compliance, or both?

Maria Ines Pinto Sanchez; Adriana Mohaidle; Andrea Baistrocchi; Dolores Matoso; Horacio Vázquez; Andrea F. Gonzalez; Roberto M. Mazure; Evangelina S. Maffei; Guillermina Ferrari; Edgardo Smecuol; Adriana Crivelli; Juan Andrés de Paula; Juan C. Gomez; Silvia C. Pedreira; Eduardo Mauriño; Julio C. Bai

AIM To determine the incidence of peripheral fractures in patients with celiac disease (CD) and the effect of treatment on fracture risk. METHODS We compared the incidence and risk of peripheral fractures before and after diagnosis between a cohort of 265 patients who had been diagnosed with CD at least 5 years before study entry and a cohort of 530 age- and sex-matched controls who had been diagnosed with functional gastrointestinal disorders. Data were collected through in-person interviews with an investigator. The overall assessment window for patients was 9843 patient-years (2815 patient-years after diagnosis). RESULTS Compared with the control group, the CD cohort showed significantly higher incidence rate and risk of first peripheral fracture before diagnosis [adjusted hazard ratio (HR): 1.78, 95% CI: 1.23-2.56, P < 0.002] and in men (HR: 2.67, 95% CI: 1.37-5.22, P < 0.004). Fracture risk was significantly associated with the classic CD presentation with gastrointestinal symptoms (P < 0.003). In the time period after diagnosis, the risk of fractures was comparable between the CD cohort and controls in both sexes (HR: 1.08, 95% CI: 0.55-2.10 for women; HR: 1.57, 95% CI: 0.57-4.26 for men). CONCLUSION CD patients have higher prevalence of fractures in the peripheral skeleton before diagnosis. This is associated with male sex and classic clinical presentation. The fracture risk was reduced after the treatment.


The American Journal of Gastroenterology | 2001

Relation between cigarette smoking and celiac disease: evidence from a case-control study.

Horacio Vázquez; Edgardo Smecuol; Daniel Flores; Roberto M. Mazure; Silvia C. Pedreira; Sonia Niveloni; Eduardo Mauriño; Julio C. Bai

OBJECTIVES:It has been suggested that environmental factors other than gliadin might play a role in pathogenesis of celiac disease. Cigarette smoking was reported to exert a protective effect against the development of symptomatic celiac disease; however, this relationship was not confirmed. The aim of this study was to determine the effect of cigarette smoking on celiac disease.METHODS:A cohort of 87 consecutive celiac disease patients attending the clinic of Malabsorption and 174 age- and sex-matched individuals diagnosed with functional GI disorder were included in the study. Clinical information was obtained both at the time of diagnosis and at follow-up by reviewing the clinical history. Smoking information was obtained through an in-person interview using a questionnaire.RESULTS:Although 33% of controls were current smokers at the time of the study, only 16% of celiac patients were smokers at diagnosis (odds ratio, 0.39; 95% confidence interval 0.19–0.79; p < 0.006). The proportion of nonsmokers among patients (84%) was significantly greater than that among controls (67%; odds ratio, 2.54; 95% confidence interval 1.27–5.16; p < 0.007). Current smoker patients had a lower baseline BMI (p < 0.05) and body weight (p < 0.05) compared to former smokers. Compared with nonsmokers, control individuals who were active smokers at entry in the study were younger (p < 0.02) and had lower body weight (p < 0.03) and BMI (p < 0.03). Interestingly, positive lineal correlation was observed between age at diagnosis and daily cigarette consumption (r = 0.72; p < 0.004) in active smokers. We did not detect any relationship either between causes for cessation of smoking and clinical symptoms or between differences in the proportions of smoking habits when patients were stratified according to their clinical status at diagnosis (symptomatic vs subclinical/asymptomatic cases).CONCLUSIONS:This study provides evidence that, compared with control subjects, a significantly lower proportion of patients with celiac disease were current smokers at the time of diagnosis, and that cigarette smoking delayed diagnosis of celiac disease. Our study suggests that the nutritional compromise of patients with celiac disease who smoked resulted from the summation of the effect of celiac disease per se and that produced by the smoking habit. Further studies are necessary to identify whether the relationship between smoking and celiac disease is causal or incidental.

Collaboration


Dive into the Silvia C. Pedreira's collaboration.

Top Co-Authors

Avatar

Luis A. Boerr

Universidad del Salvador

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Sonia Niveloni

Universidad del Salvador

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Julio C. Bai

Universidad del Salvador

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Emilia Sugai

Universidad del Salvador

View shared research outputs
Top Co-Authors

Avatar

Julio C. Bai

Universidad del Salvador

View shared research outputs
Researchain Logo
Decentralizing Knowledge