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B Drumm

Publications and source records attributed to B Drumm.

72 records · Page 4Linked to original sources
PubMed1990

Intrafamilial clustering of Helicobacter pylori infection.

Colonization of the gastric antrum by Helicobacter pylori (formerly Campylobacter pylori) has been associated with primary gastritis. We determined the frequency of colonization by H. pylori in gastric-antrum biopsy specimens from 93 children undergoing gastroscopy for the evaluation of upper gastrointestinal symptoms. We also determined H. pylori IgG antibody levels by enzyme-linked immunosorbent assay in coded serum samples from these children, family members, and control subjects of comparable ages. Among 27 children with primary, or unexplained, gastritis, H. pylori was identified by silver staining in 24 biopsy specimens and by culture in 22; specific antibodies were present in 23 children (96 percent). Three children with unexplained gastritis had no evidence of H. pylori in the antrum, nor did any of 13 children with secondary gastritis or any of 53 children with normal antral histologic features; specific antibodies were present in only 1 of these 69 children. H. pylori antibody was detected in 25 of 34 parents of colonized children, but in only 8 of 33 parents of noncolonized children (P less than 0.001). Of 22 siblings of children colonized by H. pylori, 18 had specific antibodies, as compared with only 5 of 37 controls (P less than 0.001). We conclude that H. pylori-specific IgG antibodies are associated with bacterial colonization of the gastric antrum by this organism. The intrafamilial clustering of H. pylori infection suggests that there may be person-to-person spread of these bacteria.

Adolescent↗
PubMed1990

In vitro surface properties of the newly recognized gastric pathogen Helicobacter pylori.

There appears to be a particular association between Helicobacter pylori and the gastric antrum, but the mechanisms by which the organism adheres to and colonizes the gastric mucosa are unclear. Surface hydrophobicity and surface charge mediate the adherence of other bacterial pathogens to mucosal epithelial cell surfaces. Therefore, in this study we characterized both the surface hydrophobicity and the surface charge of 10 H. pylori strains grown in broth culture. Four complementary methods were used to determine hydrophobicity: hydrophobic interaction chromatography, the salt aggregation test, comparison of bacterial adherence to polystyrene with adherence to sulfonated polystyrene, and measurement of contact angle with droplets of water. Three of the methods (salt aggregation test, adherence to polystyrene, and contact angles) indicated that each of the 10 strains expressed a relatively hydrophilic cell surface. In contrast, hydrophobic interaction chromatography determinations with both phenyl- and octyl-Sepharose suggested that the H. pylori strains were relatively hydrophobic. However, tetramethyl urea (0.4 M) did not reduce the binding of H. pylori to phenyl-Sepharose columns. DEAE-cellulose ion-exchange chromatography showed that each of the 10 strains of H. pylori had a surface which, overall, was highly negatively charged. We conclude that H. pylori expresses an overall relatively hydrophilic and negatively charged surface in vitro.

Bacterial Adhesion↗
PubMed1990

Typing of Campylobacter pylori by bacterial DNA restriction endonuclease analysis and determination of plasmid profile.

Campylobacter pylori isolates from 37 symptomatic patients and 3 asymptomatic volunteers were examined by chromosomal DNA restriction endonuclease analysis and determination of plasmid profile. Restriction digests with HindIII, HaeIII, PvuII, and BglII produced clear and reproducible results that permitted discrimination between different strains. Only 35% of C. pylori isolates were found to have plasmid DNA. Isolates from different patients, including those from two pairs of siblings, had unique restriction patterns and plasmid profiles. Consecutive isolates obtained 1 year apart from each of two asymptomatic volunteers had identical restriction patterns and plasmid profiles, suggesting persistence of the same strain. A pair of isolates obtained one year apart from the third volunteer differed in plasmid DNA content but had similar chromosomal DNA restriction patterns. Plasmid profile determination and bacterial DNA restriction endonuclease analysis provide a reliable means of discriminating between different strains of C. pylori and may be useful for typing these organisms in epidemiologic studies.

Campylobacter↗
PubMed1989

Gastric glycerolipid as a receptor for Campylobacter pylori.

A species was detected in the lipid extract of human red blood cells and human and pig stomach tissue which was specifically recognised by isolates of Campylobacter pylori. The levels of this lipid were higher in human stomach antrum than in fundus and in adult compared with infant tissue samples. Chemical treatment of the purified substance suggests that it is a novel glycerolipid.

Animals↗
PubMed1989

Adherence of bacteria to the intestine in sporadic cases of enteropathogenic Escherichia coli-associated diarrhea in infants and young children: a prospective study.

Intimate adherence of bacteria to duodenal enterocytes was demonstrated in a 12-mo-old child with sporadic diarrhea that was associated with an enteropathogenic Escherichia coli (EPEC) of the serogroup O111:K58. Therefore, a prospective study was initiated to determine if identification of EPEC in stools from sporadic cases of diarrhea of longer than 10 days in duration in children under 24 mo of age correlated with E. coli colonization of the proximal small intestine and with binding of bacteria to intestinal epithelial cells. Colonization was determined by culture of duodenal aspirates and enteroadherence by light- and electron-microscopic evaluation of both duodenal and rectal mucosa. Each EPEC isolate was examined for several previously proposed laboratory markers of virulence including alpha-hemolysin production, agglutination of erythrocytes, cell surface hydrophobicity properties, adherence to HEp-2 cells, and Verotoxin production. Ten sporadic cases of EPEC-associated diarrhea, severe enough to require hospitalization in each instance, were present among 105 patients in whom EPEC were identified in stools. Of the 10 cases, 9 were evaluated in more detail. In contrast to the first case, in the prospective study E. coli were cultured from duodenal aspirates in only 1 patient and enteroadherent organisms were not present on careful review of small bowel (0/9) and rectal (0/7) mucosa. Hemolysin production (9 of 10 EPEC strains), mannose-sensitive hemagglutination (7/10), hydrophobic cell surface properties (0/10), adherence to HEp-2 cells (7/10), and production of Verotoxin (0/10) did not distinguish the one enteroadherent EPEC from the nine EPEC strains in which in vivo enteroadherence was not documented. In this study of sporadic cases of EPEC-associated diarrhea in young children, bacterial colonization of the small bowel and enteroadherence in vivo could not routinely be demonstrated. In addition, those laboratory assays of bacterial virulence that were evaluated did not distinguish the adherent strain from nonadherent EPEC strains.

Bacterial Adhesion↗
PubMed1989

Long-term storage of Campylobacter pylori.

A reproducible method for long-term storage of Campylobacter pylori has been previously described. We cultured 10 strains of C. pylori in brucella broth that was supplemented with 10% fetal bovine serum. After incubation for 24 h, 10% glycerol and an additional 10% fetal bovine serum were added to the cultures, which when then held in storage at -70 degrees C. After 6 months, each of the strains remained viable. This technique, therefore, represents an excellent method for long-term storage of C. pylori isolates.

Campylobacter↗
PubMed1989

Bacterial cell surface hydrophobicity properties in the mediation of in vitro adhesion by the rabbit enteric pathogen Escherichia coli strain RDEC-1.

The role of hydrophobicity in the attachment of enteropathogens to gastrointestinal mucosa is controversial. In vitro binding of Escherichia coli RDEC-1 to rabbit intestine is dependent on the expression of pili. We examined in vitro adherence of piliated RDEC-1 after altering either the hydrophobicity of the organisms, the hydrophobicity of the substrate for attachment, or the surface tension of the suspending liquid. Hydrophobicity of RDEC-1 was determined using four complementary methods. In each assay piliated RDEC-1 demonstrated relatively more hydrophobic properties compared with both organisms grown to suppress pilus expression and a mutant that cannot express mannose-resistant pili. When piliated RDEC-1 were pretreated with tetramethyl urea to disrupt hydrophobic bonds surface hydrophobicity decreased. Concurrently, bacterial adherence to rabbit ileal microvillus membranes, mucus and mucin was reduced. Binding of piliated organisms to hydrophobic surfaces was significantly higher compared to both nonpiliated bacteria and the adherence of piliated RDEC-1 to relatively hydrophilic surfaces. Addition of propanol reduced the surface tension of the suspending liquid, and decreased adhesion of piliated RDEC-1 to polystyrene by 80%. Conversely, adherence of piliated organisms to a hydrophilic surface increased 12-fold after lowering the surface tension of the suspending liquid. We conclude that hydrophobic properties have a role in mediating in vitro adherence of this E. coli enteric pathogen.

Animals↗
PubMed1988

Treatment of Campylobacter pylori-associated antral gastritis in children with bismuth subsalicylate and ampicillin.

We evaluated the efficacy of medical therapy, consisting of liquid bismuth subsalicylate prescribed either in combination with oral ampicillin (n = 15) or alone (n = 1), in the clearing of bacterial colonization on the antrum in 16 children with Campylobacter pylori-associated antral gastritis. We also examined the effects of medical treatment on altering the severity of associated antral inflammation. Eight patients had upper gastrointestinal tract hemorrhage, two had acute gastric outlet obstruction, and 10 had symptoms of episodic epigastric abdominal pain. Duodenal ulcers were demonstrated in 10 of the 16 patients; in the other six, C. pylori-associated antral gastritis was documented without evidence of acute peptic ulceration. Seven days after a 6-week course of medical therapy, repeat upper endoscopy plus mucosal biopsy specimens showed that C. pylori colonization of the antrum had cleared in 12 of the 16 (75%) patients. Inflammation in the antrum improved in all patients in whom colonization by C. pylori was eradicated. In contrast, in the four with persistent colonization of the antrum, the severity of antral gastritis had not improved (p less than 0.01). Clinical symptoms improved in 9 of 12 patients in whom C. pylori colonization was no longer present, whereas subjective symptoms were unaffected in those with continued bacterial colonization of the antrum (p less than 0.05). We conclude that oral bismuth subsalicylate, in conjunction with ampicillin, can eradicate C. pylori colonization of the antrum, and that clearing of C. pylori is correlated with an improvement in the associated antral gastritis and clinical symptoms. These findings provide additional support for the hypothesis that these gastric organisms could play an etiologic role in primary antral gastritis and peptic ulcer disease.

Adolescent↗
PubMed1988

Inhibition of attachment of Escherichia coli RDEC-1 to intestinal microvillus membranes by rabbit ileal mucus and mucin in vitro.

Intestinal mucus is postulated to play a role in preventing colonization of the gastrointestinal tract by microbial pathogens. To evaluate the ability of both crude mucus and purified mucin, a glycoprotein of goblet cell origin, to inhibit mucosal adherence of enteric pathogens, we examined whether mucus and mucin derived from rabbit ileum interact with the rabbit enteropathogen Escherichia coli RDEC-1. We examined the manner in which mucus and mucin inhibited adherence of bacteria to rabbit ileal microvillus membranes (MVMs) in vitro. The purity of the mucin preparation was demonstrated by polyacrylamide gel electrophoresis before and after reduction and by showing that an antiserum raised to the mucin localized to goblet cells in rabbit intestine. Using radioactive labeling of bacteria, we quantitated attachment of RDEC-1 to MVMs, mucus, and mucin that had been immobilized on polystyrene microtiter wells. Binding of RDEC-1 to MVMs was also determined after preincubation of organisms with crude ileal mucus and purified mucin. RDEC-1 bound to both crude mucus and purified mucin when they expressed lectinlike adhesions, previously designated attachment factor rabbit 1 pili. Adherence of piliated RDEC-1 to MVMs, mucus, and mucin was significantly greater than when the bacteria were nonpiliated. Binding of piliated RDEC-1 to MVMs was decreased by preincubation of bacteria with both crude mucus (45.6 +/- 4.2% of control) and purified mucin (50.2 +/- 5.8%). These data indicate that the E. coli enteropathogen RDEC-1 can bind to purified glycoproteins of goblet cell origin and that adherence of these bacteria to mucin is mediated by expression of pili. The findings also support a role for intestinal mucus and its principal organic constituent, mucin, in preventing adherence of a known E. coli enteric pathogen to apical MVMs of enterocytes.

Animals↗
PubMed1988

Peptic ulcer disease in children: etiology, clinical findings, and clinical course.

The records of all children with peptic ulcer disease at the Hospital for Sick Children were retrospectively evaluated, excluding neonates, throughout a 5-year period. Only cases with a definite ulcer crater identified either at endoscopy or at surgery were included. There were 36 patients, 20 boys and 16 girls. Duodenal ulcers were more common than gastric ulcers (2.8:1). Ages ranged from 3 months to 17 years, with a mean age of 10 years. Patients were reviewed with respect to etiology of peptic ulcer disease, age when first examined, initial symptoms, and clinical course. Patients were divided into two groups, those with primary (n = 19) and those with secondary (n = 17) peptic ulcer disease. All peptic ulcers in patients younger than 10 years of age were secondary in nature. Secondary ulcers occurred generally in association with a severe underlying illness (11/17), and many ulcers necessitated emergency surgery because of perforation and/or severe hemorrhage (8/17). None of these patients had chronic or recurrent symptoms. In contrast, in children with primary peptic ulcer disease, initial symptoms were more benign. Most patients had abdominal pain and only one required emergency surgery. Children with primary duodenal ulcer disease had a high incidence of recurrent symptoms (67%), however, with surgery for intractable disease necessitated in 40%. Single-contrast barium meals were found to be unreliable in establishing a diagnosis of peptic ulcer disease, particularly cases of gastric ulcer disease.

Acute Disease↗
PubMed1987

Association of Campylobacter pylori on the gastric mucosa with antral gastritis in children.

We investigated the presence of Campylobacter pylori colonization of the gastric mucosa and of histologic evidence of gastritis in a prospective study of 71 consecutive children undergoing upper gastrointestinal tract endoscopy and gastric biopsies because of gastrointestinal symptoms. Two tissue samples from the gastric antrum were obtained from 67 of the 71 children (mean age [+/- SD], 11.4 +/- 3.8 years). One sample was evaluated for evidence of gastritis and stained with silver to detect organisms morphologically resembling campylobacter. The second sample was cultured for C. pylori, and a portion was used to perform a urease-screening test for the presence of C. pylori. Antral gastritis was diagnosed histologically in 18 of 67 patients. C. pylori was identified by both culture and silver staining on the antral mucosa in 7 of 10 patients with unexplained gastritis (primary gastritis) but in none of 8 patients with gastritis associated with an identifiable underlying cause (secondary gastritis). C. pylori was not identified in any of the 49 cases with normal histologic features. The urease-screening test was positive in only three of six patients with a positive culture for C. pylori. Duodenal ulcers were diagnosed by endoscopy in five patients. Each of the five had C. pylori on the antral mucosa, but organisms were not identified on the duodenal mucosa. We conclude that the presence of C. pylori on the antral mucosa is specifically associated with primary antral gastritis and may also be associated with primary duodenal ulceration.

Adolescent↗
PubMed1987

Campylobacter pyloridis-associated primary gastritis in children.

Campylobacter pyloridis are spiral-shaped Gram-negative bacteria that have recently been associated with gastritis and peptic ulcer diseases in adults. The organisms have been identified in biopsy specimens of the gastric antrum by staining sections with silver stain. To determine the frequency of colonization of the antral mucosa with C pyloridis in association with gastritis in childhood, we retrospectively reviewed 53 cases in patients (mean age 11.9 years) in whom upper endoscopy with antral biopsy was performed for the evaluation of symptoms referable to the upper gastrointestinal tract. A silver impregnation method was used to detect the presence of C pyloridis. Nineteen of 53 antral biopsy specimens showed evidence of mucosal inflammation. Ten of these 19 patients had no apparent predisposing etiology for gastritis, and six of these ten had C pyloridis identified on antral biopsies. Nine of the 19 patients had secondary causes of gastric inflammation (two gastroduodenal Crohn disease, two eosinophilic gastroenteritis, four drug related, and one dys-gamma-globulinemia and lymphonodular hyperplasia). In contrast, none of these nine patients had C pyloridis demonstrated on antral biopsies. Silver stain for C pyloridis was negative in all 34 of the 53 children who had normal antral histologic findings. C pyloridis was not demonstrated by silver stain on any of the duodenal sections, although eight of the 19 children with gastritis and nine of the 34 children with normal antral histologic findings had histologic evidence of duodenal inflammation. We conclude that C pyloridis is associated with primary antral gastritis but not with secondary gastritis in the pediatric population.

Adolescent↗
PubMedDate not supplied

Bullous mastocytosis: a fatal outcome.

A 6-week-old boy was referred with a generalized bullous rash since birth. Examination revealed bullous mastocytosis with initially no evidence of systemic involvement. Hepatosplenomegaly was noted at 6 months, and at 12 months he was found to have generalized lymphadenopathy. He developed bouts of vomiting associated with increased blistering. At 17 months he had sudden collapse following a brief bout of vomiting and was apneic and asystolic on arrival at the emergency department. The cause of death was attributed to massive hypotension secondary to mast cell degranulation. Although childhood mastocytosis has a favorable course in general, the subset of children with congenital bullous mastocytosis is at higher risk of sudden death and a more guarded prognosis should be given.

Fatal Outcome↗
PubMedDate not supplied

Guidelines for the management of Helicobacter pylori-related upper gastrointestinal diseases. Irish Helicobacter Pylori Study Group.

The discovery of H. pylori is the most important development in gastroduodenal disease this century. It has completely changed our understanding of conditions that occur in the upper gastrointestinal tract. Eradication of the bacterium will cure peptic ulcer disease, decrease the symptoms of non-ulcer dyspepsia and may prevent gastric cancer. There has been an exponential increase in the amount of research in this area in recent years and, consequently, there is considerable confusion as to how H. pylori-related conditions should be managed. It is hoped that these guidelines will clarify some of these issues.

Adult↗