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Dive into the research topics where Rodrigo Strehl Machado is active.

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Featured researches published by Rodrigo Strehl Machado.


Journal of Pediatric Gastroenterology and Nutrition | 2002

13C-Urea Breath Test With Infrared Spectroscopy for Diagnosing Helicobacter pylori Infection in Children and Adolescents

Elisabete Kawakami; Rodrigo Strehl Machado; Marialice Reber; Francy Reis da Silva Patrício

Background and Objective Studies support the accuracy of 13C-urea breath test for diagnosing and confirming cure of Helicobacter pylori infection in children. Three methods are used to assess 13CO2 increment in expired air: mass spectrometry, infrared spectroscopy, and laser-assisted ratio analysis. In this study, the 13C-urea breath test performed with infrared spectroscopy in children and adolescents was evaluated. Methods Seventy-five patients (6 months to 18 years old) were included. The gold standard for diagnosis was a positive culture or positive histology and a positive rapid urease test. Tests were performed with 50 mg of 13C-urea diluted in 100 mL orange juice in subjects weighing up to 30 kg, or with 75 mg of 13C-urea diluted in 200 mL commercial orange juice for subjects weighing more than 30 kg. Breath samples were collected just before and at 30 minutes after tracer ingestion. The 13C-urea breath test was considered positive when delta over baseline (DOB) was greater than 4.0%. Results Tests were positive for H. pylori in 31 of 75 patients. Sensitivity was 96.8%, specificity was 93.2%, positive predictive value was 90.9%, negative predictive value was 97.6%, and accuracy was 94.7%. Conclusions 13C-urea breath test performed with infrared spectroscopy is a reliable, accurate, and noninvasive diagnostic tool for detecting H. pylori infection.


Arquivos De Gastroenterologia | 2008

Decrease in prevalence of Helicobacter pylori infection during a 10-year period in Brazilian children

Elisabete Kawakami; Rodrigo Strehl Machado; Silvio Kazuo Ogata; Marini Langner

BACKGROUND Decreasing prevalence of H pylori infection has been reported in some countries. AIM To evaluate the prevalence of Helicobacter pylori infection in a 10-year period in children submitted to upper digestive endoscopy. METHODS It was a retrospective observational study. The records of 1,165 endoscopies performed during a 10-year period in a public hospital of the City of São Paulo, SP, Brazil, in patients up to 18-year-old. Only the first endoscopy was considered. Helicobacter pylori infection was defined by the rapid urease test, performed with one fragment of antral mucosa. Chi-square for trend has been estimated to compare Helicobacter pylori prevalence across the period. RESULTS The main indication for endoscopy was epigastric pain (47.4%). There were 392 patients with H pylori infection (33.6%), 12.8% being infants, 19.4% toddlers, 28.8% schoolchildren and 46.3% adolescents. Prevalence was 60.47% in the first year of the study and 30.43% in the last. Among the less than 6-year-old patients there was a decrease in infection prevalence from 25% for the 1993--6 period to 14.3% in the 2000--02 period, while among the over 12-year-old patients the decrease was from 55.5% in the first period to 39.6% in the latter. The decrease in H pylori infection prevalence was more intense within patients with epigastric pain, in which prevalence has decreased from 48.2% (92/191) in 1993--6, to 41.9% (65/155) in 1997--9 and 27.7% (57/206) in 2000--02. CONCLUSION The study suggests a significant decrease in the prevalence of H pylori infection regarding the studied patients. The trend was mainly observed in the younger age group and in patients with epigastric pain.


Helicobacter | 2004

13C-Urea Breath Test to Diagnose Helicobacter pylori Infection in Children Aged up to 6 Years

Rodrigo Strehl Machado; Francy Reis da Silva Patrício; Elisabete Kawakami

Background.  13C‐urea breath test (13C‐UBT) is an accurate noninvasive tool for diagnosis of Helicobacter pylori infection. It is considered the best method for epidemiological studies, but there are few studies to evaluate the 13C‐UBT in infants and toddlers.


Journal of Pediatric Gastroenterology and Nutrition | 2010

Validation of a monoclonal stool antigen test for diagnosing Helicobacter pylori infection in young children.

Daniele Raguza; Rodrigo Strehl Machado; Silvio Kazuo Ogata; Celso Francisco Hernandes Granato; Francy Reis da Silva Patrício; Elisabete Kawakami

Background and Objective: The monoclonal stool antigen test for diagnosing Helicobacter pylori infection in children has been tested in developed countries, showing sensitivity and specificity higher than 90%. However, its accuracy in young children from developing countries is not well established. The aim of the study was to determine the accuracy of the monoclonal stool antigen test for diagnosing H pylori infection in children up to 7 years old. Patients and Methods: Two hundred seventy-six patients (53.6% female; ages 0.35–6.99 years) were evaluated. Gold standard positive culture or positive histology and rapid urease tests were performed. The test (Amplified IDEIATM Hp StAR) was done according to the manufacturers instructions. Results were expressed as optical density (OD) and an OD more than or equal to 0.190 was considered positive. Additionally, a receiver operating characteristic curve was used to find the best cutoff. Results: The monoclonal stool antigen test for diagnosing H pylori infection showed 100% sensitivity (95% confidence interval [CI] 92.7%–100%) and 76.2% specificity (95% CI 70.1%–81.4%), considering the manufacturers cutoff. After setting a new cutoff with the receiver operating characteristic curve (OD = 0.400), sensitivity remained 100% (95% CI 92.7%–100%), but the specificity improved to 97.7% (95% CI 94.7%–99%). At ages up to 2 years, sensitivity was 100% (95% CI 43.8%–100%) and specificity was 100% (95% CI 92.4%–100%); at ages 2 to 4 years, 100% (95% CI 80.6%–100%) and 97.6% (95% CI 96%–99.2%); at ages older than 4 years, 100% (95% CI 88.6%–100%) and 96.6% (95% CI 94.7%–98%), respectively. Conclusions: The monoclonal stool antigen test is accurate for diagnosing H pylori in children younger than 7 years old, but it must be locally validated in order to find the best cutoff for each population.


The Journal of Pediatrics | 2012

Ten-Year Experience Using Antegrade Enemas in Children

Suzanne M. Mugie; Rodrigo Strehl Machado; Hayat Mousa; Jaya Punati; Mark J. Hogan; Marc A. Benninga; Carlo Di Lorenzo

OBJECTIVE To describe a single-center, 10-year experience with the use of antegrade enemas. STUDY DESIGN Retrospective analysis of 99 patients treated with antegrade enemas at Nationwide Childrens Hospital. RESULTS Study subjects (median age 8 years) were followed for a mean time of 46 months (range 2-125 months) after cecostomy placement. Seventy-one patients had the cecostomy placed percutaneously and 28 by surgery. Thirty-five patients had functional constipation and 64 patients an organic disease (spinal abnormalities, cerebral palsy, imperforate anus, Hirschsprungs disease). While using antegrade enemas, 71% became symptom-free, in 20 subjects symptoms improved, in 2 subjects symptoms did not change, and in 7 subjects symptoms worsened. Poor outcome was associated with surgical placement of the cecostomy (P < .001), younger age (P = .02), shorter duration of symptoms (P = .01), history of Hirschsprungs disease (P = .05), cerebral palsy (P = .03), previous abdominal surgery (P = .001), and abnormal colonic manometry (P = .004). In 88%, successful irrigation solution included use of a stimulant laxative, and subjects who used a stimulant did significantly better (P < .001) than subjects who started without a stimulant. In 13 patients, the cecostomy was removed 49.7 months after placement without recurrence of symptoms. Major complications occurred in 12 patients and minor complications in 47. CONCLUSIONS Antegrade enemas represent a successful and relatively safe therapeutic option in children with severe defecatory disorders. Prognostic factors are identified.


Sao Paulo Medical Journal | 2010

Seroprevalence of Helicobacter pylori infection among children of low socioeconomic level in São Paulo

Aurea Cristina Portorreal Miranda; Rodrigo Strehl Machado; Edina Mariko Koga da Silva; Elisabete Kawakami

CONTEXT AND OBJECTIVE Helicobacter pylori infection is mainly acquired during childhood, and is associated with significant morbidity in adults. The aim here was to evaluate the seroprevalence and risk factors of H. pylori infection among children of low socioeconomic level attended at a public hospital in São Paulo, Brazil. DESIGN AND SETTING Cross-sectional study, among patients attended at an outpatient clinic. METHODS 326 children were evaluated (150 boys and 176 girls; mean age 6.82 ± 4.07 years) in a cross-sectional study. Patients with chronic diseases or previous H. pylori treatment, and those whose participation was not permitted by the adult responsible for the child, were excluded. The adults answered a demographic questionnaire and blood samples were collected. The serological test used was Cobas Core II, a second-generation test. Titers > 5 U/ml were considered positive. RESULTS H. pylori infection was diagnosed in 116 children (35.6%). Infected children were older than uninfected children (7.77 ± 4.08 years versus 5.59 ± 3.86 years; p < 0.0001). The seroprevalence increased from 20.8% among children aged two to four years, to 58.3% among those older than 12 years. There were no significant relationships between seropositivity and gender, color, breastfeeding, number of people in the home, number of rooms, bed sharing, living in a shantytown, maternal educational level, family income or nutritional status. In multivariate analysis, the only variable significantly associated with H. pylori seropositivity was age. CONCLUSION Infection had intermediate prevalence in the study population, and age was associated with higher prevalence.


Jornal De Pediatria | 2010

Prevalência de parasitoses intestinais em crianças do Parque Indígena do Xingu

Mario Luis Escobar-Pardo; Anita Paula Ortiz de Godoy; Rodrigo Strehl Machado; Douglas Rodrigues; Ulysses Fagundes Neto; Elisabete Kawakami

OBJECTIVE: To evaluate the prevalence of intestinal parasitoses in Native Brazilian children from 2 to 9 years old. METHODS: A search for ova and parasites was conducted in the stools of children between 2 to 9 years old living in six indigenous villages located in the Middle and Lower Xingu River, to wit: Pavuru, Moygu, Tuiarare, Diauarum, Capivara, and Ngojwere. The study utilized the Paratest kit® (Diagnostek, Brazil) to preserve collected stools. Fecal samples were shipped to the Laboratory of the Pediatric Gastroenterology Division of the UNIFESP/EPM, in Sao Paulo, for analysis. The search for ova and parasites was performed utilizing the Hoffman method, and later through optical microscopic evaluation. Fecal samples were collected one year apart from each other. RESULTS: There were no significant statistical differences between the mean ages of the children from the six indigenous villages studied. The search for ova and parasites found positive results for the stools of 97.5% (198/202) and 96.1% (98/102) of children in the first and second collections, respectively. There was no statistical association with the childrens age. The search performed one year later found no differences in the proportion of parasites identified in the first collection for protozoa (93.3% in 2007 versus 93.3% in 2008, McNemar = 0.01, p = 0.1) or for helminths (37.1% in 2007 versus 38.2% in 2008, McNemar = 0.03, p = 0.85). There were significant differences in prevalence of Entamoeba coli between 2007 (43.8%) and 2008 (61.8%) (McNemar Chi 6.1; p = 0.0135). There were no significant differences for other parasites when comparing the results of the two studies. CONCLUSION: The high prevalence of intestinal parasitosis matched the elevated rates of environmental contamination in this indigenous community.


Journal of Pediatric Gastroenterology and Nutrition | 2013

Gastroesophageal reflux causing sleep interruptions in infants.

Rodrigo Strehl Machado; Frederick W. Woodley; Beth Skaggs; Carlo Di Lorenzo; Mark Splaingard; Hayat Mousa

Background and Aim: Little is known about the relation between gastroesophageal reflux (GER) episodes and sleep interruptions in infants. The aim of the study was to evaluate the relationship between GER and the incidence of sleep interruptions in infants. Methods: Study patients included 24 infants (younger than 1 year) referred for multichannel intraluminal impedance and esophageal pH monitoring with simultaneous polysomnography. Exclusion criteria were a previous fundoplication and studies lasting <20 hours. Tests were clinically indicated to investigate suspicion of GER-related apnea (17, 70.8%), stridor (6, 25%), noisy breathing (2, 8.3%), and cyanotic spells (1, 4.2%). Most patients presented with significant comorbidities (19, 79.2%). Results: The number of nonacid GER (NAGER) per hour was greater during sleep time than during daytime and awakening following sleep onset (median 0.27 vs 1.85 and 1.45, P < 0.01). A total of 1204 (range 7–86 per infant) arousals in 24 infants was detected, 165 (13.7%) that followed GER episodes, and 43 (3.6%) that preceded GER episodes. Seven patients presented with a positive symptom association probability for arousals; 5 were exclusively because of NAGER. A positive symptom association probability for awakenings was detected in 9 patients; 4 were because of NAGER, 4 were because of AGER, and 1 was because of both NAGER and GER. Patients with awakenings related to GER presented longer mean clearance time of AGER during sleep (165.5 vs 92.8 seconds, P = 0.03). Conclusions: GER was a frequent cause of interrupting sleep among our infant patients, and NAGER proved to be equally important as AGER for causing arousals and awakenings in infants.


Journal of Pediatric Gastroenterology and Nutrition | 2010

Helicobacter pylori and Iron-deficiency Anemia in Adolescents in Brazil

Litza Neves Araf; Carlos Alberto de Bragança Pereira; Rodrigo Strehl Machado; Daniele Raguza; Elisabete Kawakami

Aim: The aim of the study was to evaluate the association between Helicobacter pylori infection and iron deficiency (ID) in adolescents attending a public school. Patients and Methods: From March to June 2001, a cross-sectional study was conducted among adolescents (10–16 years) enrolled in a single public school in São Paulo, Brazil. Of 400 eligible students, 195 agreed to participate, but 1 was excluded due to sickle cell disease. A blood sample was collected from each subject to measure hemoglobin and ferritin. H pylori status was investigated with the 13C-urea breath test. All of the subjects with either anemia or ID were given iron therapy. Results: H pylori prevalence was 40.7% (79/194), being higher in male subjects (45/90 vs 34/104, P = 0.014). There was no relation between infection and nutritional status. Abnormally low serum ferritin was observed in 12 subjects, half of whom were positive for H pylori (odds ratio [OR] 1.49, 95% confidence interval [CI] 0.38–5.81). The median serum ferritin was 33.6 ng/mL (interquartile range 23.9–50.9) in infected subjects and 35.1 ng/mL (interquartile range 23.7–53.9) in uninfected subjects. Anemia was detected in 2% (4/194) of the students, half of whom were infected (OR 1.47, 95% CI 0.1–20.6). The mean hemoglobin value in infected subjects was 13.83 g/dL ± 1.02 versus 14 g/dL ± 1.06 in uninfected subjects. Conclusions: The study was not able to find a relation between H pylori infection and ID or anemia.


Jornal De Pediatria | 2008

Furazolidone, tetracycline and omeprazole: a low-cost alternative for Helicobacter pylori eradication in children

Rodrigo Strehl Machado; Marcello Ruiz da Silva; Aírton Viriato

OBJECTIVES To evaluate furazolidone, tetracycline and omeprazole as first line therapy for Helicobacter pylori in children with digestive symptoms. METHODS Prospective and consecutive open trial. The study included patients older than 8 years old with functional dyspepsia, functional abdominal pain, severe histological abnormalities (intestinal metaplasia, gastric atrophy or mucosa-associated lymphoid tissue lymphoma) or peptic ulcer. H. pylori status was defined based both upon histology and rapid urease test. Drug regimen was a 7-day course of omeprazol, tetracycline (or doxycycline) and furazolidone twice daily. Eradication was assessed by upper endoscopy 2 months after treatment (histology and rapid urease test). Further clinical evaluation was done 7 days and 2 months after treatment. RESULTS Thirty-six patients (21 female/15 male) were included. Age ranged from 8 to 19 years (mean 12.94+/-2.89 years). On intention-to-treat analysis (n = 36), eradication rate was 83.3% (95%CI 77.1-89.5) whereas in per-protocol analysis (n = 29), it was 89.7% (95%CI 84.6-94.7). Compliance was better when doxycycline was used, but the success rates were similar for the two tetracyclines. There was no variable associated with treatment failure. Side effects were reported in 17 patients (47.2%), mainly abdominal pain (11/30.5%), nausea (seven/19.4%) and vomiting (five/13.9%). CONCLUSION Triple therapy with furazolidone and tetracycline is a low-cost alternative regimen to treat H. pylori infection.

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Elisabete Kawakami

Federal University of São Paulo

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Hayat Mousa

University of California

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Carlo Di Lorenzo

Nationwide Children's Hospital

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Douglas Rodrigues

Federal University of São Paulo

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Ulysses Fagundes Neto

Federal University of São Paulo

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Silvio Kazuo Ogata

Federal University of São Paulo

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Mario Luis Escobar-Pardo

Federal University of São Paulo

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Anita Paula Ortiz de Godoy

Federal University of São Paulo

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