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M Guelrud

Publications and source records attributed to M Guelrud.

At least 19 recordsLinked to original sources
PubMed2001

Comparison of PCR and common clinical tests for the diagnosis of H. pylori in dyspeptic patients.

Helicobacter pylori has been recognized as a major gastric pathogen. The objective of this study was to assess the diagnostic value of common clinical tests to detect H. pylori infection, by comparison with PCR. Serum and gastric biopsy specimens from 106 dyspeptic patients were examined. Serology was performed with Pyloriset Dry test, and biopsies were examined histologically, for rapid urease activity and PCR amplification of an ureA gene segment of H. pylori. PCR primers were specific for H. pylori and required at least 1.47 pg of H. pylori DNA, corresponding to about 800 bacterial cells. According to serology, histology, rapid urease, and PCR, positive results were respectively found in 56%, 86%, 64%, and 85% of dyspeptic patients, primarily with gastritis. Relative to PCR, the sensitivity (and specificity) was 55% (38%) for serology, 86% (13%) for histology, 70% (69%) for urease. When combining histology and urease, Bayesian analysis of data indicated no advantage of using combined methods over rapid urease test alone. Histology should not any longer be considered a gold standard test for Helicobacter pylori. Urea breath test still seems the first option for non invasive diagnostic. If an invasive diagnostic is justified, highly specific and sensitive molecular methods should be used to examine specimens.

Bayes Theorem↗
PubMed2001

Enhanced magnification endoscopy: a new technique to identify specialized intestinal metaplasia in Barrett's esophagus.

BACKGROUND: Specialized intestinal metaplasia (SIM) in Barrett's esophagus (BE) is not identifiable by standard endoscopy. Acetic acid instillation enhances the ability to detect columnar epithelium at the squamocolumnar union. Enhanced magnification endoscopy involves the combined use of magnification endoscopy with acetic acid. This study assessed the value of enhanced magnification endoscopy in detecting SIM in patients with BE. METHODS: Patients undergoing endoscopic surveillance because of short segment BE without dysplasia underwent enhanced magnification endoscopy with 1.5% acetic acid instillation. Standard endoscopy was followed by magnification endoscopy and repeated after acetic acid spraying. Surface patterns were characterized prior to and after acetic acid spraying. The observed surface patterns were compared with histology results. RESULTS: Forty-nine patients, 9 women and 39 men, with a mean age of 50.5 years were studied. One was excluded because of unclear definition of the surface pattern. Enhanced magnification endoscopy detected 4 different mucosal surface patterns: I, round pits; II, reticular; III, villous; and IV, ridged. A total of 129 areas were examined. Standard endoscopy identified an endoscopic pattern in 1.5% of the areas, standard endoscopy and acetic acid in 8.5%, magnification endoscopy alone in 38%, and enhanced magnification endoscopy in all 129 endoscopic areas. The yields for detecting SIM according to endoscopic patterns were as follows: pattern I, 0%; II, 11% (odds ratio 0.5, p = 0.54); III, 87% (odds ratio 36, p = 0.001); and IV, 100% (odds ratio 14, p = 0.015). CONCLUSIONS: Enhanced magnification endoscopy is an accurate method of predicting SIM in BE. The simplicity of the technique and its ability to identify characteristic endoscopic patterns with outstanding clarity and resolution that correlate with histologic identification of specialized intestinal metaplasia make enhanced magnification endoscopy an excellent method for the evaluation of patients with BE.

Acetic Acid↗
PubMed2001

Endoscopic retrograde cholangiopancreatography.

Endoscopic retrograde cholangiopancreatography has been widely applied as a diagnostic and therapeutic procedure in adult patients with pancreacticobiliary disorders and has recently become an accepted modality in pediatrics. This article reviews the general concepts of diagnostic endoscopic retrograde cholangiopancreatography in children and specific therapeutic interventions and results in different diseases.

Biliary Tract Diseases↗
PubMed1999

Normal and anomalous pancreaticobiliary union in children and adolescents.

BACKGROUND: The normal length of the pancreaticobiliary union (common channel) in the pediatric population is not known, nor is the frequency of anomalous pancreaticobiliary union and the extent to which it is associated with pancreaticobiliary disease. METHODS: ERCP was performed on 136 patients younger than 1 year (group 1) and 128 older than 1 year (group 2). RESULTS: In group 1 the average length of the common channel was 1.8 +/- 0.61 mm with a maximal length of 3 mm (mean plus 2 standard deviations). In group 2 the average length and maximal length of the common channel increased with age. In the 1 to 3 year age range the average length was 2.2 +/- 0.47 mm with a maximal length of 2.7 mm, in the 4 to 6 year range it was 2.8 +/- 0.40 mm (3.6 mm maximal), in the 7 to 9 year range it was 3.2 +/- 0.43 mm (4.1 mm maximal), in the 10 to 12 year range it was 3.9 +/- 0.5 mm (4.4 mm maximal), and in the 13 to 15 year range it was 4.0 +/- 0.51 mm (5 mm maximal). The prevalence of the anomalous pancreaticobiliary union was 25% (66/264). In group 1 the anomaly was present in 4.4% (6 of 136) of patients, 1.3% (1/76) with neonatal hepatitis, 4.6% (3/44) with biliary atresia, and 100% (2/2) with choledochal cyst. In group 2 the anomaly was present in 46.9% (60/128) of patients, 100% (57/57) with choledochal cyst and 15.7% (3/19) with idiopathic recurrent pancreatitis without bile duct dilatation. CONCLUSIONS: The mean length of the common channel increases with age. The maximum normal length of the common channel in neonates and infants younger than 1 year is 3 mm. It increases with age to a maximum of 5 mm in children and adolescents between 13 and 15 years of age. Anomalous pancreaticobiliary union is relatively common among children and adolescents undergoing ERCP in our center, including those with idiopathic recurrent pancreatitis (15.7%). ERCP is valuable in the diagnosis of this anomaly.

Adolescent↗
PubMed1999

Sphincter of Oddi dysfunction in children with recurrent pancreatitis and anomalous pancreaticobiliary union: an etiologic concept.

BACKGROUND: The exact cause of recurrent pancreatitis among patients with anomalous pancreaticobiliary union is not known. Sphincter of Oddi dysfunction has been implicated as a mechanism. This study evaluated sphincter of Oddi function in children with anomalous pancreaticobiliary union and recurrent pancreatitis and assessed the results of endoscopic sphincterotomy in the management of this condition. METHODS: We retrospectively reviewed 128 endoscopic retrograde cholangiopancreatographic (ERCP) studies performed on children older than 1 year and adolescents with pancreaticobiliary disease. In 64 instances, ERCP was performed because of recurrent pancreatitis. Nine patients underwent sphincter of Oddi manometry followed by endoscopic sphincterotomy, and these patients were included in this study. A basal pressure greater than 35 mm Hg was considered diagnostic for sphincter of Oddi dysfunction. Follow-up data were obtained retrospectively from the patients' relatives and referring physicians. RESULTS: An anomalous pancreaticobiliary union was found in 18 of 64 (28%) patients with recurrent pancreatitis. The 9 patients who underwent sphincter manometry and endoscopic sphincterotomy were 5 girls and 4 boys 2.9 to 17 years of age (mean 7.8 years). A choledochal cyst was found in 7 of these 9 patients. Two patients had anomalous pancreaticobiliary union without common bile duct dilatation. All 9 patients had sphincter of Oddi dysfunction (mean basal pressure 96 +/- 37.8 mm Hg, range 48 to 156 mm Hg). The length of the common channel was 22.8 +/- 5.5 mm, and the length of the sphincter of Oddi segment was 12.1 +/- 1.9 mm (p < 0.001). In all patients the sphincter of Oddi segment was located within the duodenal wall. The mean follow-up period after endoscopic sphincterotomy was 26.4 months (range 18 to 38 months). Eight patients had excellent results defined as absence of symptoms and no subsequent episodes of acute pancreatitis. Treatment of 1 patient was considered moderately successful because the patient still had occasional pain without pancreatic enzyme elevation but no subsequent episodes of acute pancreatitis. One patient had mild postprocedural pancreatitis. CONCLUSIONS: Recurrent pancreatitis and anomalous pancreaticobiliary union are associated with sphincter of Oddi dysfunction in children and adolescents. Endoscopic sphincterotomy is beneficial to these patients.

Adolescent↗
PubMed1998

Acetic acid improves identification of remnant islands of Barrett's epithelium after endoscopic therapy.

BACKGROUND: Instillation of acetic acid onto the uterine cervix at colposcopy has been used for many years to highlight dysplastic areas and thereby enhance the ability to obtain targeted biopsy specimens. As part of an ongoing trial of multipolar electrocoagulation for Barrett's esophagus, we sought to develop a simple technique to identify small islands of residual specialized columnar epithelium after treatment. METHODS: In 21 consecutive patients, 5 to 10 mL of 1.5% acetic acid was sprayed onto the distal esophagus using a spray catheter, followed immediately by spraying 50 mL of tap water. RESULTS: Initially, a whitish coloration developed in both esophageal and gastric epithelia. After 2 to 3 minutes, the esophageal squamous mucosa remained white but the columnar epithelium became reddish. Remnant islands of Barrett's epithelium were outlined by a white rim. CONCLUSION: Acetic acid instillation enhances the ability to detect small or indistinguishable remnant islands of columnar epithelium after endoscopic treatment of Barrett's esophagus. This method is safe, rapid, and inexpensive.

Acetic Acid↗
PubMed1998

Endoscopic therapy of pancreatic disease in children.

The advent of endoscopic retrograde cholangiopancreatography (ERCP) has revolutionized the approach to the diagnosis and management of pancreatic disorders in adults. In the past 5 years, endoscopic pancreatic therapy in children has moved from an investigational concept to a practical service provided by specialized centers. When performed by experienced endoscopists, therapeutic pancreatography can be successfully performed in a selected group of children with a low rate of complications.

Child↗
PubMed1997

Modification of Christensen urease test as an inexpensive tool for detection of Helicobacter pylori.

About half the world population is infected with Helicobacter pylori. Most live in developing countries where clinical studies face the constraints of high costs of imported rapid diagnostic tests. In this work, we describe and validate a simple local urease test (LUT) to determine the presence of the bacterium in gastric biopsies, and report the incidence of infection among symptomatic patients in Caracas, Venezuela. Statistical comparison of LUT and CLOtest (Delta West, Bentley, Australia) (N = 216 patients) showed that the probability of 95% agreement between the two test was 0.936. Overall incidence of infection determined by the LUT was 65% (N = 229), and it was higher in patients from public (72%; N = 153) than from private (50%; N = 76) hospitals (p = .001). Therefore, the incidence of infection differs in two socioeconomic groups that coexist in the same city. LUT may represent an affordable tool in clinical studies needed to identify social factors that increase the risk of infection by H. pylori.

Adolescent↗
PubMed1996

Endoscopic retrograde cholangiopancreatography in children.

In the past two decades, the possibility to visualize the biliary tree and the pancreatic duct using endoscopic retrograde cholangiopancreatography (ERCP) has substantially influenced evaluation and treatment of adult patients with suspected pancreaticobiliary disease. Development of pediatric duodenoscopes, expansion of indications for the procedure in children, and availability of newly skilled pediatric endoscopists have resulted in an increasing number of these procedures being performed in children. Operative endoscopic procedures are also applicable to children and adolescents; techniques such as endoscopic sphincterotomy, biliary drainage, common bile duct stone and pancreatic duct stone extraction, implantation of endoprosthesis, and pancreatic pseudocyst drainage are beginning to be used in children, with an overall success rate similar to that seen in adult patients. Techniques, indications, complications, and diagnostic and therapeutic applications of ERCP in the pediatric population are defined.

Biliary Tract Diseases↗