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O Gutierrez

Publications and source records attributed to O Gutierrez.

At least 19 recordsLinked to original sources

Post-transplant hypophosphatemia: Tertiary 'Hyper-Phosphatoninism'?

Hypophosphatemia is a common complication of kidney transplantation. Tertiary hyperparathyroidism has long been thought to be the etiology, but hypophosphatemia can occur despite low parathyroid hormone (PTH) levels and can persist after high PTH levels normalize. Furthermore, even in the setting of normal allograft function, hypophosphatemia, and hyperparathyroidism, calcitriol levels remain inappropriately low following transplantation, suggesting that mechanisms other than PTH contribute. Fibroblast growth factor-23 (FGF-23) induces phosphaturia, inhibits calcitriol synthesis, and accumulates in chronic kidney disease. We performed a prospective, longitudinal study of 27 living donor transplant recipients to test the hypotheses that excessive FGF-23 accounts for hypophosphatemia and decreased calcitriol levels following kidney transplantation. Hypophosphatemia <2.5 mg/dl developed in 85% of subjects, including one who had previously undergone parathyroidectomy; 37% developed phosphate < or =1.5 mg/dl. The mean pre-transplant FGF-23 level was 1,218+/-542 RU/ml. Within the first week following transplantation, mean levels decreased to 557+/-579 RU/ml, which were still above normal. FGF-23 was independently associated with serum phosphate (P < 0.01), urinary excretion of phosphate (P < 0.01), and calcitriol levels (P < 0.01); PTH was not independently associated with any of these parameters. We calculated area under the curve for FGF-23 and PTH between the pre- and first post-transplant levels as a summary measure of early exposure to these phosphaturic hormones. An area under the FGF-23 curve greater than the median was associated with a relative risk of developing hypophosphatemia < or =1.5 mg/dl of 5.3 (P = 0.02) compared with lower levels. Increased area under the PTH curve was not associated with greater risk of hypophosphatemia. Excessive FGF-23 exposure in the early post-transplant period appears to be more strongly associated with post-transplant hypophosphatemia than PTH.

Adult↗

Oral anticoagulant treatment: risk factors involved in 500 intracranial hemorrhages.

Intracranial bleeding is the most severe complication caused by anticoagulant or antiplatelet treatment. The increasing use of this therapy, especially in older people, makes the balance between clinical benefit and bleeding risk an important consideration. A retrospective study of all consecutive 500 intracranial hemorrhages in the West Valladolid area, approximately 220,000 people, during the period 1998 to 2004, was performed. In relation to mortality, predisposing conditions were included, such as age, antithrombotic treatment, arterial hypertension, cancer, blood diseases, vascular malformations, and traumatisms. The incidence of intracranial hemorrhage was 310 per 100,000 per year with a mortality of 30%. Higher mortality was found in antiplatelet-treated patients (44.9%) than in anticoagulated patients (31.1%). This may be related to a different mean age of 78 vs. 71 years. Arterial hypertension was the most frequent risk factor (45.1% in nontreated patients, 60% anticoagulated, and 75.5% antiplatelet). The relative risk of intracranial bleeding in anticoagulated patients was 11.2 (p < 0.001) with an incidence of 0.03% and a median of 14 months since treatment began. The median INR was 3.3. In 40% of the patients the previous five controls were in range. Strict consideration of indications criteria joined to a better control of risk factors may avoid intracranial bleeding episodes.

Adolescent↗

Helicobacter pylori outer membrane proteins and gastroduodenal disease.

BACKGROUND AND AIMS: A number of Helicobacter pylori outer membrane proteins (OMPs) undergo phase variations. This study examined the relation between OMP phase variations and clinical outcome. METHODS: Expression of H pylori BabA, BabB, SabA, and OipA proteins was determined by immunoblot. Multiple regression analysis was performed to determine the relation among OMP expression, clinical outcome, and mucosal histology. RESULTS: H pylori were cultured from 200 patients (80 with gastritis, 80 with duodenal ulcer (DU), and 40 with gastric cancer). The most reliable results were obtained using cultures from single colonies of low passage number. Stability of expression with passage varied with OipA > BabA > BabB > SabA. OipA positive status was significantly associated with the presence of DU and gastric cancer, high H pylori density, and severe neutrophil infiltration. SabA positive status was associated with gastric cancer, intestinal metaplasia, and corpus atrophy, and negatively associated with DU and neutrophil infiltration. The Sydney system underestimated the prevalence of intestinal metaplasia/atrophy compared with systems using proximal and distal corpus biopsies. SabA expression dramatically decreased following exposure of H pylori to pH 5.0 for two hours. CONCLUSIONS: SabA expression frequently switched on or off, suggesting that SabA expression can rapidly respond to changing conditions in the stomach or in different regions of the stomach. SabA positive status was inversely related to the ability of the stomach to secrete acid, suggesting that its expression may be regulated by changes in acid secretion and/or in antigens expressed by the atrophic mucosa.

Adenocarcinoma↗

CagA in Barrett's oesophagus in Colombia, a country with a high prevalence of gastric cancer.

BACKGROUND: In the USA, atrophic gastritis and gastric cancer are rare, whereas gastro-oesophageal reflux disease (GERD) is common. Infection with Helicobacter pylori, especially a CagA positive strain, is unusual in patients with GERD/Barrett's oesophagus in the USA. AIM: To examine the relation between Barrett's oesophagus and CagA positive H pylori in Colombia, a country with a high prevalence of CagA positive H pylori associated atrophic gastritis and gastric cancer. METHODS: Helicobacter pylori and CagA status was determined among Colombian patients with long segment Barrett's oesophagus and a control group with simple H pylori gastritis. Helicobacter pylori status was determined using a triple stain and CagA status was determined by immunohistochemistry using a specific rabbit anti-CagA serum. RESULTS: Gastric and oesophageal mucosal biopsies were obtained from 51 patients--39 men (mean age, 57.8 years; SD, 13.1) and 12 women (mean age, 51.8 years; SD, 14.4)--with documented long segment Barrett's oesophagus. The results were compared with 24 Colombian patients with H pylori gastritis without oesophageal disease. Thirty two patients with Barrett's oesophagus had active H pylori infection. CagA status was evaluated in a subset of 23 H pylori infected patients with Barrett's oesophagus, and was positive in eight of these patients compared with 19 of 24 controls (p = 0.01). CONCLUSIONS: Although most Colombian patients with Barrett's oesophagus had H pylori infection, CagA positive infections were unusual. These data illustrate how consistent corpus inflammation reduces acid secretion, which prevents Barrett's oesophagus among those with abnormal gastro-oesophageal reflux barriers.

Adult↗

Atrophic gastritis in young children and adolescents.

BACKGROUND: Helicobacter pylori associated gastric cancer arises via a multistage process, with atrophic gastritis being the precursor lesion. Helicobacter pylori is typically acquired in childhood, yet little is known of the prevalence of atrophic gastritis in childhood. AIM: To study atrophic gastritis among children from countries with high gastric cancer incidence. METHODS: Sections from topographically mapped gastric biopsy specimens from children undergoing clinically indicated endoscopy in Korea and Colombia were evaluated using visual analogue scales. Atrophy was defined as loss of normal glandular components, including replacement with fibrosis, intestinal metaplasia (IM), and/or pseudopyloric metaplasia of the corpus (identified by the presence of pepsinogen I in mucosa that was topographically corpus but phenotypically antrum). RESULTS: One hundred and seventy three children, 58 from Korea (median age, 14 years) and 115 from Colombia (median age, 13 years), were studied. Helicobacter pylori was present in 85% of Colombian children versus 17% of Korean children (p<0.01). Atrophic mucosa near the antrum-corpus border was present in 16% of children, primarily as pseudopyloric metaplasia (31%, IM; 63%, pseudopyloric metaplasia; 6%, both). The median age of children with corpus atrophy was 15 (range, 7-17) years. CONCLUSION: Gastric atrophy occurs in H pylori infected children living in countries with high gastric cancer incidence. Identification and characterisation of the natural history of H pylori gastritis requires targeted biopsies to include the lesser and greater curve of the corpus, starting just proximal to the anatomical antrum-corpus junction, in addition to biopsies targeting the antrum and cardia.

Adolescent↗

Geographic differences in the distribution of intestinal metaplasia in duodenal ulcer patients.

OBJECTIVE: A strong correlation exists between atrophic gastritis and the intestinal type of gastric carcinoma. Duodenal ulcer disease characteristically has an antral predominant gastritis and a lower risk for gastric cancer. The aim of this study was to investigate the extent and distribution of intestinal metaplasia in duodenal ulcer in countries differing in gastric cancer incidence. METHODS: Topographically mapped gastric biopsy specimens (median 11) were obtained from patients with duodenal ulcer in four countries (Korea, Colombia, USA, and South Africa). Sections were stained with a triple stain and evaluated for Helicobacter pylori (H. pylori), active inflammation, and intestinal metaplasia. RESULTS: One hundred and sixty-five patients with duodenal ulcer were examined (29 from Korea, 52 from Colombia, 62 from the USA, and 22 from South Africa). The percentage of biopsies with intestinal metaplasia was significantly greater in Korean patients (86%) compared with that in other countries (50%) (p = 0.0004). Intestinal metaplasia was most prevalent in the antrum lesser curve and greater curve, and the body lesser curve. Intestinal metaplasia was present in the gastric corpus of 38% of duodenal ulcer patients from Korea compared with an average of 10% elsewhere (p = 0.018). No differences were observed in the density or distribution of H. pylori infection or in the degree of active gastritis between countries. CONCLUSIONS: Although antral predominant gastritis is the prevalent pattern of gastritis in duodenal ulcer, intestinal metaplasia in the gastric corpus may be found with geographic differences. These findings suggest that duodenal ulcer and gastric cancer are not mutually exclusive diseases but are rather ends of the spectrum of H. pylori infection.

Adult↗

Molecular epidemiology of Helicobacter pylori: separation of H. pylori from East Asian and non-Asian countries.

The predominant H. pylori strain circulating among geographic locations differs with regard to the genomic structure. This study determined whether structural subtypes of the cagA 3' repeat region could be used to identify the population of origin of H. pylori isolates. We examined 600 cagA-positive H. pylori (Colombia, 100; USA, 100; France, 100; Canada, 20; Italy, 20; Korea, 100; Japan, 100; Hong Kong, 20; Taiwan, 20; Vietnam, 20). The cagA 3' region was amplified by PCR using primers specific to Japanese and Western 3' cagA gene sequences. PCR using Japanese cagA primers resulted in PCR products in 99-6 % of strains from East Asia but no non-Asian strains. Conversely, PCR using Western cagA primers resulted in amplicons in 100% of non-Asian strains, and only one from East Asia. cagA genotyping is useful for molecular epidemiological studies as strains can be completely separated by differences in the cagA 3' region.

Adult↗

Molecular identification of main cellular lineages as a tool for the classification of gastric cancer.

Gastric carcinomas (GC) are heterogeneous tumors comprising variable amounts of cells of different lineage phenotype, including gastric mucous cells (surface--SMC or gland--GMC) and intestinal cells (IC). The evaluation of tumor behavior has classically depended on strictly morphological classifications of tumors. Microsatellite instability (MSI) is frequently detected in GC, but whether MSI affects all gastric cellular lineages or exclusively occurs in unique cellular lineages in GC is not known. The aims of this study were to test a combination of anti-mucin antibodies to classify gastric cancer into predominant cell lineage phenotype and to determine whether MSI in GC is associated with particular cellular tumor phenotypes. Fifty-five GC were immunophenotyped with antibodies specific for SMC, GMC, or IC. DNA was extracted from tumor and non-neoplastic gastric tissues and amplified with 5 microsatellite markers. A mixed cellular pattern was the most frequent phenotype of GC (61%) and was seen in both glandular (63%) and diffuse (58%)-type tumors. No significant difference in the rate of MSI was found in tumors with predominant gastric, intestinal or mixed phenotype. However, tumors with null or low-level expression of cellular lineage differentiation markers displayed MSI more frequently than tumors with high-level expression (40% v 20%). In conclusion, different gastric carcinoma cell lineage patterns can be easily identified with the 3 immunohistochemical markers used in this study. The 3 main cellular lineage components of gastric cancer can be similarly affected by microsatellite instability, consistent with the notion that MSI is an early event in gastric carcinogenesis.

Adult↗

Topographic patterns of intestinal metaplasia and gastric cancer.

OBJECTIVE: The role of intestinal metaplasia in gastric oncogenesis has been demonstrated by both cross-sectional and longitudinal studies. This study was designed to determine whether, in a population at high risk for gastric cancer, different topographical patterns and phenotypes of intestinal metaplasia were associated with different degrees of cancer risk. METHODS: A total of 68 Colombian patients with gastric cancer and 67 controls with nonulcer dyspepsia were studied by an extensive biopsy protocol. Intestinal metaplasia was assessed semiquantitatively by histology and was characterized histochemically. In both patients and controls, the Spearman's correlation test was applied to the test if the gastric distribution of metaplastic lesions resulted in specific topographical patterns associated with different risks for cancer. RESULTS: Four topographical patterns of intestinalization emerged: 1) "Focal," in 14 cancer patients and 16 controls; 2) "Antrum-predominant," in seven cancer patients and six controls; 3) "Magenstrasse" (involving the lesser curvature from cardia to pylorus) in 25 cancer patients and four controls. This pattern was associated with higher cancer risk (OR = 5.7; 95% CI: 1.3-26) than were the two less extensive patterns; and 4) "Diffuse," involving essentially the entire gastric mucosa with the exception of the fundus, was unique to 13 cancer patients. The OR for cancer was 12.2; 95% CI: 2.0-72.9. Incomplete-type metaplasia significantly correlated with the extent of total metaplasia and was also associated with greater cancer risk. CONCLUSIONS: In a population with high risk for gastric cancer, the extension of intestinal metaplasia correlates with the extent of its "incomplete" phenotype and is significantly associated with increased cancer risk. Both the extent and location of intestinal metaplasia along the lesser curvature (from the cardia to the prepyloric zones) identify patients with the highest cancer risk.

Adenocarcinoma↗

Relationship between the cagA 3' repeat region of Helicobacter pylori, gastric histology, and susceptibility to low pH.

BACKGROUND & AIMS: The variation in size of Helicobacter pylori CagA is related to repeat sequences in the 3' region of the cagA gene. We investigated whether structural subtypes of the cagA 3' region are associated with presentation of the infection or to susceptibility to acid. METHODS: We examined 319 cagA-positive H. pylori isolates: 84 isolates from Bogota, Colombia; 83 from Houston, Texas; 24 from Siena, Italy; and 128 from Seoul, Korea. The cagA 3' region was amplified by polymerase chain reaction. Gastric histology and susceptibility to pH 3 were evaluated in relation to the number of cagA repeat regions. RESULTS: Strains with more than three repeat regions were associated with significantly higher scores for gastric mucosal atrophy and intestinal metaplasia than those with fewer repeat regions. H. pylori strains with three repeat regions were also significantly more susceptible to pH 3 than isolates with fewer repeat regions. CONCLUSIONS: H. pylori strains with more than three repeat regions in the 3' region of the cagA gene are associated with enhanced histological injury and with reduced survival in acidic conditions. It is hypothesized that these variants arise within the stomach.

Adult↗

Marked differences in the frequency of microsatellite instability in gastric cancer from different countries.

OBJECTIVE: Previous studies have reported variable rates of microsatellite instability (MSI) in gastric cancer. We investigated the frequency of MSI in invasive gastric carcinoma of patients from three geographic regions. METHODS: Genomic DNA from gastric cancer and nontumor tissue from 22 Korean, 20 Colombian, and 26 U.S. patients was amplified with five microsatellite markers. RESULTS: MSI was more frequently seen in gastric cancer from Korea, affecting 50% of patients, in contrast with gastric cancers from the U.S. (7%) and Colombia (15%) (p = 0.003 and p = 0.03, respectively). MSI at one locus was significantly more frequent in gastric cancer from individuals >65 yr (p = 0.01). MSI was similarly associated with both diffuse and intestinal types of gastric cancer. CONCLUSIONS: MSI affects the two major histological types of gastric cancer, and was more frequent in gastric cancer from Korea than in the other countries, suggesting that the relative importance of different pathways of gastric carcinogenesis may vary in diverse regions of the world.

Aged↗

Relationship between Helicobacter pylori iceA, cagA, and vacA status and clinical outcome: studies in four different countries.

There is continuing interest in identifying Helicobacter pylori virulence factors that might predict the risk for symptomatic clinical outcomes. It has been proposed that iceA and cagA genes are such markers and can identify patients with peptic ulcers. We compared H. pylori isolates from four countries, looking at the cagA and vacA genotypes, iceA alleles, and presentation of the infection. We used PCR to examine iceA, vacA, and cagA status of 424 H. pylori isolates obtained from patients with different clinical presentations (peptic ulcer, gastric cancer, and atrophic gastritis). The H. pylori isolates examined included 107 strains from Bogota, Colombia, 70 from Houston, Tex., 135 from Seoul, Korea, and 112 from Kyoto, Japan. The predominant genotype differed among countries: the cagA-positive iceA1 vacA s1c-m1 genotype was predominant in Japan and Korea, the cagA-positive iceA2 vacA s1b-m1 genotype was predominant in the United States, and the cagA-positive iceA2 vacA s1a-m1 genotype was predominant in Colombia. There was no association between the iceA, vacA, or cagA status and clinical outcome in patients in the countries studied. iceA status shows considerable geographic differences, and neither iceA nor combinations of iceA, vacA, and cagA were helpful in predicting the clinical presentation of an H. pylori infection.

Antigens, Bacterial↗

The differential diagnosis of early gastric mucosa-associated lymphoma: polymerase chain reaction and paraffin section immunophenotyping.

The distinction between benign florid lymphoid hyperplasia and low-grade gastric mucosal-associated lymphoid tissue (MALT) lymphoma may be a challenge. The presence of monoclonal B cells in Helicobacter pylori-chronic active gastritis has suggested that polymerase chain reaction (PCR) data should be viewed with caution. We investigated the reliability of PCR versus immunophenotyping in diagnosing early gastric MALT lymphoma. We studied 1511 biopsies from eight patients with high-grade primary gastric lymphoma, 25 with low-grade MALT lymphoma, 32 with atypical lymphoid infiltrates, and 39 with Helicobacter pylori-chronic active gastritis. Paraffin sections from all cases were stained with antibodies to CD20, CD3, AE1/AE3, kappa and lambda. PCR was performed on paraffin sections using the primer set VH-FR3/J(H). Using histopathology as the gold standard in diagnosis, we confirmed monoclonality in 22 of 25 MALT lymphomas (88%); a clonal band was found in 38% (15 of 39) of patients with chronic active gastritis. An immunophenotype pattern with predominance of CD20-positive cells in lymphocytic infiltrates was associated with monoclonality in 92% of cases. The presence of an enlarged irregular mantle zone was found in both monoclonal and polyclonal areas. An equal prevalence of B and T cells in lymphocytic infiltrates was associated with a polyclonal pattern in 24 of 31 cases (77%). Immunostaining of sIg (kappa and lambda) was difficult in paraffin sections and convincing proof of monoclonality was not obtained. Lymphoepithelial lesions were infrequent in gastric biopsies and their presence was highlighted with keratin stains. Because monoclonal B cells are observed in Helicobacter pylori-associated gastritis, the correct interpretation of clonality by PCR remains unclear. Paraffin section IHC using CD20 and CD3 is especially useful to confirm the diagnosis of gastric MALT lymphoma.

Adult↗

Takayasu arteritis in Colombia.

Takayasu arteritis has been recognized in Colombia just recently, and so far we do not have any report concerning its presentation here. In this first report, some issues related to the presentation of the disease are indicated and compared with those found in the medical literature. No differences were found in age and sex. Most of the cases were diagnosed during an inactive phase of the disease with advanced manifestations due to vascular lesion which suggests the existence of some genetic factor influencing such a presentation, or may be the consequence of a delay in diagnosing the disease during initial and active stages due to not suspecting it. Comparing the vessels which are affected among other races and countries, we can find both differences and similarities. With the purpose of discovering the demographic, clinical, angiographic and laboratorial characteristics of Takayasu arteritis in Colombia, the present study was carried out by studying 35 clinical cases in different medical centers of the country.

Adolescent↗

Microflora of gastric biopsies from patients with duodenal ulcer and gastric cancer: a comparative study of patients from Korea, Colombia, and the United States.

It remains unclear why the spectrum of H. pylori-related diseases differs among different geographic regions. We examined the non-H. pylori contamination rates of the stomach in patients with duodenal ulcer or gastric adenocarcinoma from three different regions with different spectra of H. pylori-related diseases. Gastric biopsies were cultured from patients with duodenal ulcer or histologically proven gastric cancer from Seoul, Korea; Bogota, Colombia; and Houston, Texas. The frequency of non-H. pylori contamination was tallied in relation to the clinical diagnosis. Cultures from 247 duodenal ulcer patients and 165 patients with gastric cancer had bacterial growth. H. pylori was isolated from 207 (73.7%) patients with duodenal ulcer and 90 (47.1%) patients with gastric cancer (P < 0.001). In patients with duodenal ulcer (DU) or gastric cancer (GC), the rate of positive cultures for H. pylori were not statistically different (P > 0.143 for DU, P > 0.190 for GC) between regions. The frequency of isolation ranged from 69% to 79% for DU patients and from 39% to 50% for gastric cancer patients. Non-H. pylori bacterial contamination was found more frequently (63%) in Colombian duodenal ulcer patients compared to 30% ulcer patients from the United States or Korea (P < 0.001). Non-H. pylori growth occurred in 50.8-75.5% of cancer patients and was significantly lower in US patients than in patients from either Colombia or Korea (P < 0.01). The geographic location as well as disease status affects the rate of H. pylori recovery and non-H. pylori contamination of the stomach and may play a role in the geographic differences in manifestation of H. pylori infection. The fact that the proportion of gastric cancer patients in the United States with non-H. pylori contamination was significantly less than that of Korea or Colombia shows that the notion of an almost universal increase in gastric microbial content in gastric adenocarcinoma should be reconsidered.

Adenocarcinoma↗

Cure of Helicobacter pylori infection improves gastric acid secretion in patients with corpus gastritis.

BACKGROUND: For more than 30 years it has been known that gastric acid secretion is inversely related to the extent and severity of corpal gastritis. We therefore evaluated the effect of cure of Helicobacter pylori infection on basal and pentagastrin-stimulated acid secretion. METHODS: Basal acid output (BAO) and maximal acid output (MAO) were assessed in 11 H. pylori-infected dyspeptic patients (8 women and 3 men; mean age, 28 years) before and after successful anti-H. pylori therapy. RESULTS: The gastritis index was significantly lower after therapy and was associated with an increase in both BAO and MAO after cure of the H. pylori infection (BAO from 0.3 mmol/h and MAO from 4.8 mmol/h to 19 mmol/ h). Basal and stimulated acid concentrations also increased (29.1 +/- 36.6 to 54 +/- 31 mmol/l and 72.5 +/- 46 to 120.1 +/- 30 mmol/l, respectively, for basal and stimulated acid concentrations; P < 0.05 for peak and MAO, P = 0.07 for BAO). CONCLUSION: Gastric acid secretion increased into the normal range after successful treatment of H. pylori infection, suggesting that gastric function can recover to normal or almost normal after cure of H. pylori infection.

Adult↗

A prospective, parallel, double-blind comparison of iodixanol and iohexol in extremity phlebography.

RATIONALE AND OBJECTIVES: A two-center, prospective, double-blind study was conducted to compare the performance parameters (efficacy, safety, and injection-associated discomfort) of iohexol with those of the new, isosmolar contrast medium iodixanol in extremity phlebography. METHODS: Ninety-nine patients from two centers, for whom venography was clinically indicated, were blindly randomized into two groups, iohexol at 300 mg I/ml (IOH 300) or iodixanol at 270 mg I/ml (IOD-270). Patient vital signs and reports of adverse events were recorded for a minimum of 1 hr and monitored until the outcome was known. Any discomfort associated with the injection was also recorded. Laboratory measures included urinalysis, creatinine levels in serum and blood urea nitrogen. RESULTS: Both contrast media provided good or excellent visualization in nearly all patients (100% of patients in the IOD-270 group and 96% in the IOH-300 group). The incidence of adverse reactions was low in both groups (8.5% in the IOD-270 group and 10% in the IOH-300 group). Injection associated discomfort lasting less than 4 min occurred in nine patients, four in the IOD-270 group and five in the IOH-300 group. Although clinically relevant changes in vital signs occurred in more than half the patients, most were judged to be anxiety related. Review of laboratory data revealed no evidence of toxicity for either agent. There was no statistically significant difference between the two agents with regard to any of these observed parameters. CONCLUSION: The data support the conclusion that both IOD-270 and IOH-300 are safe and effective agents when used for adult phlebography and are associated with little injection-site discomfort.

Adult↗

Adherence of Helicobacter pylori to areas of incomplete intestinal metaplasia in the gastric mucosa.

BACKGROUND & AIMS: Helicobacter pylori is not usually found in areas of intestinal metaplasia. Thus, the development of intestinal metaplasia has been viewed as a mechanism by which the stomach eliminates H. pylori. The aim of this study was to evaluate the frequency of H. pylori adherence to intestinal metaplasia in different populations. METHODS: Mapped gastric biopsy specimens from 378 H. pylori-positive subjects from various geographical regions were examined. Intestinal metaplasia was typed by staining with periodic acid-Schiff/alcian blue and high-iron diamine/alcian blue. RESULTS: In 32 patients, H. pylori was found in intimate contact with intestinal metaplasia. This was documented by electron microscopy. All areas of intestinal metaplasia showing adherence contained sulfomucins and had no brush border. Posttreatment biopsy specimens from 4 patients whose infection was not cured showed persistence of H. pylori in intestinal metaplasia. CONCLUSIONS: These patients may have a strain of H. pylori with unusual adhesion characteristics, or their type of intestinal metaplasia may have biochemical properties that make it hospitable for H. pylori. The exclusive association of H. pylori adherence with incomplete intestinal metaplasia (a putative precursor of carcinoma) and its greater frequency in Koreans (a population at risk for gastric cancer) suggest that this phenomenon may play a role in the hypothetical sequence metaplasia > dysplasia > carcinoma.

Bacterial Adhesion↗