Gastric inflammation is enhanced in children with CagA-positive Helicobacter pylori infection

BACKGROUND: Helicobacter pylori infection is likely to be acquired at an early age. The factors leading to active inflammation in childhood, however, are largely unknown. SUBJECTS AND METHODS: We determined the CagA status, the best characterized virulence factor of H. pylori, and serum antibodies of IgG and IgA classes to H. pylori in 39 infected children. RESULTS: Mononuclear cell infiltration in the antrum but not in the gastric body was more intense in CagA-positive children than in CagA-negative children. The degree of polymorphonuclear cell infiltration on the other hand was independent of the CagA status. The antibody titers of IgG and IgA classes to H. pylori were higher in CagA-positive than in CagA-negative infections (P<0.001 and P<0.01, respectively). IgG antibody titers to H. pylori correlated directly with the density of mononuclear and polymorphonuclear cell infiltration in the gastric antrum but not in the gastric body. CONCLUSION: H. pylori-infected children with CagA antibodies seem to have a more severe inflammation in the gastric antrum than CagA-negative children as shown by an increase in the density of antral mononuclear cells. A finding of higher serum antibody titers to H. pylori in CagA-positive children may be related to this enhancement of inflammation.     

Gastric histopathology, iron status and iron deficiency anemia in children with Helicobacter pylori infection

OBJECTIVES: Helicobacter pylori has been established as a major cause of gastritis and peptic ulcer disease in adults and children. H. pylori infection may also have a role in the development of some extra-gastrointestinal diseases, including iron deficiency anemia. The aim of this study is to investigate H. pylori-related changes in gastric physiology and histology and the relationship of these changes to iron deficiency anemia in children. METHODS: Fifty-two patients with gastrointestinal complaints were studied. Hematologic parameters, 3-day vitamin C and iron consumption, serum gastrin levels, and gastric juice ascorbic acid levels were compared in patients with and without H. pylori infection. Dietary intake of vitamin C and iron, serum gastrin, gastric juice ascorbic acid content, and gastric histology were compared in patients with H. pylori infection and anemia and in patients with H pylori infection and no anemia. The CagA status of the H. pylori organisms was evaluated. RESULTS: Twenty-eight of 52 patients had H. pylori. Thirty-one patients had iron deficiency anemia. H. pylori infection was associated with low serum iron levels. H. pylori gastritis was associated with a decrease in the gastric juice ascorbic acid level. Infection with CagA-positive strains was associated with a greater decrease in gastric juice ascorbic acid than infection with CagA-negative strains. However, the gastric juice ascorbic acid levels of patients with H. pylori and anemia were not different from those of non-anemic patients with H. pylori. Among patients with H. pylori infection, pangastritis was twice as common in those with anemia than in those without anemia. CONCLUSIONS: H. pylori infection was associated with a decrease in gastric juice ascorbic acid concentration, and this effect was more pronounced in patients with the CagA-positive strain. Pangastritis was more common in patients whose H. pylori.infection was accompanied by anemia.     

幽门螺杆菌细胞毒素相关蛋白与胃窦黏膜炎症程度、细菌定植密度的关系

目的探讨幽门螺杆菌(Hp)细胞毒素相关蛋白(CagA)与慢性胃炎患儿胃窦黏膜炎症程度、Hp定植密度的关系。方法对79例Hp相关性慢性胃炎患儿采用免疫印迹法检测血清CagA抗体,并行胃镜检查,取胃窦黏膜经HE及改良Giemsa 染色后观察胃窦黏膜炎症程度及Hp定植密度。结果79例Hp相关性慢性胃炎患儿血清CagA抗体阳性67例(84.81%),其中胃窦黏膜轻度炎症9例(13.43%),中重度炎症58例(86.57%),而12例血清CagA抗体阴性患儿胃窦黏膜轻度炎症7例(58 33%),中重度炎症5例(41 67%),两者差异有显著性(x2=10.076 P=0.002),而两组胃窦黏膜Hp定植密度无明显差异(H=0.246 P-0 884)。结论CagA与慢性胃炎患儿胃窦黏膜炎症程度有关.而与Hp在胃窦部的定植密度无关,CagA 阳性Hp菌株能引起胃窦黏膜较重炎症。     

Gastric emptying of solids in children with H. pylori-positive and H. pylori-negative non-ulcer dyspepsia

OBJECTIVE: There is currently no data available in children on possible relationships among Helicobacter pylori, gastric motility and gastric inflammation. This is a prospective study of gastric emptying (GE) in symptomatic children with and without H. pylori who met symptom-based criteria for non-ulcer dyspepsia (NUD). METHODS: 47 consecutive dyspeptic patients (23 males; age range, 7 to 18 years) were enrolled. All patients had extensive negative diagnostic investigations. Scintigraphic solid-phase gastric emptying was assessed. RESULTS: 21 H. pylori-positive and 26 H. pylori-negative patients were identified with non-ulcer dyspepsia. The groups were not different in clinical symptoms except that pain related to feeding was more frequent in infected children (P < 0.03). Nodular antral gastritis was found more frequently in the H. pylori positive group (P < 0.0001). The gastritis score was more severe in H. pylori infected than H. pylori negative patients in both fundic and body mucosa (P < 0.001). Within the H. pylori-positive NUD group, the mean half-time GE of a solid meal was significantly accelerated compared to the non-infected group (P < 0.05). There was no difference in the intragastric food distribution and curves of gastric emptying of both groups. A significant relationship was found between the degree of gastric body inflammation gastric emptying, but not antral inflammation. Gastric emptying rate did not differ by sex or age of the subjects in either group. CONCLUSIONS: In dyspeptic children with H. pylori, gastric emptying of a solid was significantly accelerated compared with symptomatic H. pylori uninfected patients. This suggests that H. pylori is able to induce gastric emptying acceleration. Our findings add more information on H. pylori infection and gastroduodenal disease.     

CagA antibodies as a marker of virulence in chilean patients with Helicobacter pylori infection

BACKGROUND: The bacterial and host factors that influence the clinical outcomes of the Helicobacter pylori infection have not been fully identified. Cytotoxin-associated gene product (CagA), one of the virulence factors, has been associated with a more aggressive form of infection. The authors studied the relationship between CagA status and clinical outcome in Chilean children and adults with H. pylori infection. METHODS: One hundred eighty consecutive patients undergoing upper gastrointestinal endoscopic analysis were enrolled after informed consent was obtained. Rapid urease test and histologic analysis were used to detect H. pylori infection. IgA and IgG antibodies to H. pylori whole cell antigen preparation and IgG antibodies to CagA were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: H. pylori infection was detected in 42% of the patients by biopsy or urease test and in 38% and 20% of patients by IgG and IgA antibodies, respectively. The prevalence of H. pylori either by the invasive or the serologic tests was directly related to patient age. Among patients with H. pylori, there was no significant association between age and prevalence of CagA. Nearly 70% of the patients with H. pylori and peptic ulcer disease had CagA-positive strains. In contrast, only 49% of the patients with chronic gastritis alone had CagA-positive strains (P < 0.05). CONCLUSIONS: In Chile, patients infected with H. pylori have a proportion of CagA-positive strains similar to that reported in developed countries. CagA prevalence was not significantly different in adults and children infected with H. pylori, suggesting that variations in clinical outcome may be related to host immune or environmental factors.     

幽门螺杆菌相关性胃肠粘膜病患儿血清CagA抗体、VacA抗体检测及其临床意义

为了解幽门螺杆菌（elicobacter pylori,H.pylori)相关性胃肠粘膜病患儿血清中细胞毒素相关基因抗原（CagA)、空泡毒素抗原（VasA)的有无及其临床意义，应用免疫印迹法对46例慢性胃炎和25例消化性溃疡患儿血清CagA抗体、VacA抗体进行了检测。结果：（1）慢性胃炎小儿血清H.Pylori CagA抗体（＋）、VacA抗体（＋）检出率为28．3％，消化性溃疡患儿为64．0％，两组比较差异有显著性（P＜0．05）；（2）对慢性胃炎炎症活动程度进行分组检测，中、重度急性活动性胃炎患儿中H.Pylori CagA抗体（＋）、VacA抗体（＋）检出率为50．0％，与轻症者比较差异有显著性（P＜0．05）。提示H.pylori菌株存在不同致病能力，CagA、VasA是致小儿H.Pylori相关性胃肠粘膜病重要的毒力因素；通过检测CagA、VacA抗体，可及时指导临床治疗。     

Nature and extent of gastric lesions in symptomatic Chilean children with Helicobacter pylori-associated gastritis

Chile has one of the highest rates of gastric cancer in the world and most children and adolescents in the country are colonized by Helicobacter pylori. This study assessed the nature and extent of the gastric lesions in 73 consecutive patients aged 5-17 y, referred for upper gastrointestinal endoscopy. Their H. pylori-associated gastric pathology was characterized and these data were compared with their sociodemographic status. Endoscopic assessment was normal in 43 patients while in 30 there was a variety of mucosal lesions. Sixty patients (83%) had histological chronic gastritis of the antrum and in 45 (63%) the lesions also involved the gastric corpus; 90% of patients with chronic gastritis were colonized by H. pylori. Although most of these patients had epithelial erosions and dedifferentiation of the pit epithelium, atrophy and metaplasia were not found. Patients' socioeconomic status was inversely correlated with their rate of colonization by H. pylori (p < 0.005), the frequency of gastric lesions on endoscopy (p < 0.01) and the frequency of involvement of antral and corpus mucosa by chronic gastritis (p < 0.002). This latter feature was positively correlated with age (p < 0.001). Conclusion: This study shows a high frequency of extensive lesions of H. pylori-associated chronic gastritis in young Chilean patients. This histological picture is consistent with the hypothesis of a H. pylori-associated progressive gastric pathology which may represent a major factor in the high local rate of gastric cancer.     

Helicobacter pylori and nonulcer dyspepsia in childhood: clinical pattern, diagnostic techniques, and bacterial strains

BACKGROUND: This is a report of the results of a multicenter study performed in children with dyspepsia from five pediatric centers in Puglia, a region in southern Italy. In the study, clinical features of Helicobacter pylori infection, the reliability of diagnostic techniques, and the involvement of bacterial strains were examined. METHODS: Fifty-three outpatients with dyspepsia enrolled in our study and compiled a diary recording clinical symptoms in patients before they underwent the following diagnostic techniques: endoscopy, biopsy for histologic analysis, rapid urease test, 13C urea breath test, serology specific for immunoglobulin (Ig)G and anti-CagA and VacA. RESULTS: H. pylori showed a prevalence of 30.2% (n = 16). Histologic positivity was seen in all patients at the antral level (H. pylori-associated chronic gastritis). In the gastric body, bacterial chronic active gastritis was present only in six patients (H. pylori-associated chronic pangastritis). Clinical evaluation showed a significant difference in favor of subjects positive for H. pylori only for epigastric burning and/or pain (p < 0.001). The comparison of results of diagnostic tests, using histology as the gold standard, showed sensitivity and specificity of more than 93% for 13C urea breath test and more than 85% for rapid urease test and serology. Anti-CagA antibodies were found in 64.3% and anti-VacA antibodies in 42.8% of H. pylori-positive patients. CONCLUSIONS: H. pylori prevalence in children with dyspepsia from the geographic area studied is comparable with that found in other developed countries. Approximately 50% of the studied patients were infected by cytotoxic strains. The urea breath test was the most reliable noninvasive diagnostic tool and is suitable for routine use, although endoscopy with histologic assessment remains the definitive investigation and is particularly important in patients with positive serology for CagA and VacA. Finally, the frequency of aggressive strains in our region seems to affect the clinical pattern; this emphasizes the importance of definitive diagnosis in children and offers a new role for serology.     

Endoscopic nodular gastritis: an endoscopic indicator of high-grade bacterial colonization and severe gastritis in children with Helicobacter pylori

OBJECTIVE: To investigate the significance of endoscopic nodular gastritis associated with Helicobacter pylori infection. METHODS: This prospective study included 185 children (50.8% boys) aged 1 to 12 years (mean, 6.9 +/- 3.0 years) who underwent upper intestinal endoscopy during evaluation of chronic abdominal pain. The authors assessed the endoscopic appearance of the stomach, noting those patients with endoscopic nodular gastritis. Urease activity of gastric mucosal biopsies was measured. With histologic examination, the presence and density of H. pylori organisms, the presence of follicular gastritis, the nature of inflammation, and the gastritis activity grade and overall gastritis score were assessed. RESULTS: H. pylori infection was identified in 50 children (27%). Endoscopic nodular gastritis was significantly associated with active chronic gastritis and follicular gastritis. Nodularity in the stomach showed a high specificity (98.5%) and positive predictive value (91.7%) for the diagnosis of H. pylori infection and was observed in 22 of 50 (44%) H. pylori-positive patients and in 2 of 135 (1.5%) H. pylori-negative patients. A significant association was observed between older age and the prevalence of this finding (P< 0.001). There was a significant increase in endoscopic nodular gastritis with increased H. pylori density and a positive correlation (Pearson coefficient = 0.97) with increased gastritis score on histologic examination. Increase in gastritis score was dependent on increased H. pylori density in patients with gastric nodularity; this finding was independent of age. CONCLUSIONS: Endoscopic findings of antral nodularity in children suggest the presence of H. pylori infection and follicular gastritis and may identify cases of severe gastritis and marked bacterial colonization.     

儿童幽门螺杆菌感染的菌株类型及治疗

目的评估幽门螺杆菌(H.pylori)不同菌株对儿童胃粘膜炎症程度和治疗效果。方法对94例经胃镜和活检确诊H.pylori相关性胃炎的5～14岁儿童,用免疫印迹试验测血清细胞毒相关蛋白(CagA)、细胞空胞毒素(VacA)、尿素酶(urase)亚型抗体;抗H.pylori三联疗法10d,67例分A组(LAC组,用奥美拉唑 克拉霉素 阿莫仙治疗)和B组(BCF组,用果胶铋 克拉霉素 呋喃唑酮治疗),停药4周后用13C-UBT测定H.pylori根除率。结果①94例中检出CagA和/或VacA阳性86.2%,CagA和/或VacA阴性13.8%;慢性胃炎(CSG)27%,CSG 十二指肠球炎(DG)48%,CSG DG 十二指肠溃疡(DU)21%,胃溃疡(CU) DU4%,滤泡样改变56%,各种疾病检出菌株差异无显著性(χ2=2.551,P>0.05)。②94例H.pylori根除率76%,其中A组90.32%(28/31例),消化性溃疡(PU)根除率100%(12/12例)、CSG根除率84.21%(16/19例);B组H.pylori根除率为88.89%(32/36例),PU76.00%(6/8例),CSG92.86%(26/28例),两组差异无显著性(P>0.05)。各菌株根除率差异无显著性(P>0.05)。症状消退慢、难治及未能根除者大多为阳性菌。结论H.pylori蛋白印迹法简单、可靠,是流行病学筛选H.pylori细胞毒素的指标;阳性患儿必须予以根治。以下各组患儿推荐根治:①慢性活动性胃炎H.pylori阳性者;②胃十二指肠溃疡病患者;③产细胞毒素CagA阳性者。LAC三联根治H.pylori相关性胃炎疗程短、副作用小和根除率高,值得推广。     

Increased mucosal inflammatory cytokines in children with Helicobacter pylori-associated gastritis

The concentrations of tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-1-β in tissue homogenates of gastric mucosal biopsy specimens, and in gastric juice samples from Helicobacter pylori-positive and -negative children, were determined. The study population comprised 30 children with recurrent abdominal pain attending upper gastrointestinal endoscopy. Of these patients 18 were infected with H. pylori. Cytokine concentrations in gastric biopsy homogenate supernatants and in gastric juice were measured by enzyme-linked immunosorbent assay (ELISA). TNF-α levels in gastric juice and in gastric biopsy homogenate supernatants in patients with H. pylori-positive gastritis were found to be significantly higher than those in children without H. pylori infection. IL-6 levels were also higher in H. pylori -infected subjects, but the difference in IL-6 concentrations measured in gastric juice and biopsy homogenate supernatants did not reach statistical significance. IL-1-β concentrations in both specimens showed no significant difference between the two groups of children. It was suggested that increased levels of inflammatory cytokines, especially TNF-α and IL-6 generated locally within the gastric mucosa might be implicated in the pathogenesis of H. pylori-associated gastritis in childhood.     

Cytokines in the gastric mucosa of children with Helicobacter pylori infection

AIM: Few studies have looked at the cytokine profile in gastric mucosa in children with Helicobacter pylori infection. This study investigated cytokines and their effects on histological abnormalities in the gastric mucosa of children with H. pylori infection. METHODS: The levels of interferon-gamma (IFN-gamma), interleukin-4 (IL-4) and IL-8 proteins were measured in biopsy specimens from the gastric antrum and corpus of children with H. pylori infection, and related to inflammatory cell infiltrations. RESULTS: The antral and corporal mucosal levels of IFN-gamma and IL-8 proteins were significantly higher in children with H. pylori infection than in uninfected children, but there was no such difference in the levels of IL-4 protein. The antral mucosal level of IL-8 protein was significantly higher than the corporal mucosal level of IL-8 protein in the infected children. Inflammatory cell infiltration was significantly higher in the infected children than in the uninfected children, but there were no significant correlations between mucosal cytokine levels and inflammatory cell infiltrations. CONCLUSION: The results suggest that the predominant Th1 cytokine response and enhanced IL-8 production in the mucosa may be involved in the gastric inflammation seen in children infected with H. pylori, as well as in adult patients.     

儿童CagA+幽门螺杆菌感染根治前后胃黏膜上皮细胞增殖、凋亡和P53蛋白水平表达的对比研究

目的研究幽门螺杆菌（Hp）感染胃黏膜上皮细胞增殖、凋亡和突变型P53蛋白水平的表达情况,以及Hp感染根除治疗前后胃黏膜上皮细胞增殖、凋亡指数变化。方法采用脱氧核糖核酸末端转移酶介导的缺口末端标记技术（TUNEL）以及PCNA免疫组织化学法对30例CagA^＋Hp感染患儿和30例Hp阴性患儿胃黏膜上皮细胞增殖、凋亡情况进行比较,同时对突变型P53基因蛋白的表达情况进行检测。CagA蛋白抗体的检测采用Western Blot2．1免疫印迹法。结果CagA^＋Hp感染组胃黏膜上皮细胞增殖指数为11．56％±4．21％,较Hp阴性组（5．85％±2．21％）高（t=7．57,P〈0．01）;凋亡指数CagA^＋Hp感染组（10．58％±5．31％）较Hp阴性组（2．86％±0．64％）高（t=8．096,P〈0．01）。30例CagA^＋Hp感染组有28例完成了三联药物的Hp根除治疗,2例失访,其中21例根除,7例未根除;21例cagA’Hp感染根除治疗后,胃黏膜上皮细胞增殖指数治疗前为（11．50％±4．11％）,治疗后为（6．30％±3．26％）（t=3．968,P〈0．01）。凋亡指数治疗前为（10．58％±4．02％）,治疗后为（3．74％±2．30％）（t=6．69,P〈0．01）。7例未根除治疗患儿胃黏膜上皮细胞增殖指数及凋亡指数变化无统计学意义。cagA’Hp感染组胃黏膜上皮细胞P53阳性表达率63％（19／30）;在P53阳性表达中,轻度2例,中度8例,重度9例。Hp阴性组胃黏膜上皮细胞P53阳性表达率16％（5／30）,均为轻度表达。CagA^＋Hp感染组P53阳性表达率高于Hp阴性感染组（X2=6．805,P〈0．01）。结论CagA^＋Hp感染可引起胃黏膜上皮细胞增殖、凋亡的变化,使黏膜增殖、凋亡动态失衡,黏膜的不稳定性增加,突变型P53基因蛋白异常表达可能参与此过程的调控。     

Parietal cell antibodies and Helicobacter pylori in children

BACKGROUND: Gastric autoantibodies are common in Helicobacter pylori-infected adults, and the presence of these antibodies is associated with atrophic gastritis. The role of H. pylori in the autoimmune type of atrophic gastritis is unresolved, and it is not known at what stage the autoantibodies appear in serum during H. pylori infection. Therefore, we screened children with and without H. pylori infection for gastric parietal cell antibodies. METHODS: Seventy-one children with H. pylori infection verified by examination of gastric biopsy specimens (mean age, 9.4 years), 8 children with positive serology but negative histology for H. pylori (mean age, 11.6 years), and 130 children with negative serology for H. pylori (mean age, 7.7 years) were screened for the presence of gastric parietal cell antibodies in serum by indirect immunofluorescence. In addition, 61 children with celiac disease (mean age, 7.1 years) were screened for gastric parietal cell antibodies and H. pylori antibodies. RESULTS: None of the children with H. pylori infection had gastric parietal cell antibodies in serum. Only three positive parietal cell antibody reactions were found: a 14-year-old boy with positive serology for H. pylori but no other signs of infection (titer 5000), a 14-year-old girl with tuberculosis (titer 1250, seronegative for H. pylori) and a 10-year-old girl with insulin-dependent diabetes mellitus (titer 6250, seronegative for H. pylori). CONCLUSIONS: Although gastric autoantibodies are often found in adults with chronic H. pylori gastritis, it seems that H. pylori-infected children are not positive for gastric parietal cell antibodies. It remains to be studied in which H. pylori infections and at what stages gastric autoantibodies appear.     

Helicobacter pylori and Meckel's diverticula

BACKGROUND: Helicobacter pylori is known to infect only gastric mucosa and is strongly associated with gastroduodenal ulceration. The authors studied whether H. pylori colonizes the gastric mucosa of Meckel's diverticula, and determined its relationship to "gastritis" and bleeding. METHODS: A 10-year retrospective review identified 45 children with Meckel's diverticulum. Hematoxylin-eosin and Diff-Quik stains were used to assess the presence and severity of gastritis, and to highlight organisms in the resected diverticula. Cases with organisms were then studied with antibodies specific for H. pylori using immunoperoxidase methods. RESULTS: Twenty-eight children, 7 months to 12.6 years of age, had lower gastrointestinal hemorrhage caused by Meckel's diverticulum and had positive radionuclide scans. All had acid-secreting mucosa in their diverticula, and ulceration. "Chronic gastritis" and eosinophilia were constant findings; "acute gastritis" was present in four patients. Twenty specimens exhibited lymphoid follicles in the gastric mucosa. Seventeen patients with Meckel's diverticula (age range, 1 month-14.7 years) who presented with acute abdominal pain associated with intussusception were used for comparison. Acid-secreting gastric mucosa was seen in four patients. H. pylori was identified in only one of the 45 patients; this patient had ulceration and moderate "acute gastritis." CONCLUSIONS: H. pylori does not colonize a substantial number of children who have ulcerated and bleeding Meckel's diverticulum in the presence of acid-secreting mucosa. Although H. pylori is a notable cause of ulceration, the authors confirm that ulceration is possible in its absence, and alternative mechanisms of ulceration are important. The presence of lymphoid follicles in Meckel's diverticula, unlike gastric biopsies, is not associated with H. pylori.     

A rapid serologic test and immunoblotting for the detection of Helicobacter pylori infection in children

The gold standard for the diagnosis of Helicobacter pylori infection requires an endoscopic biopsy of gastric mucosa for histological examination, urease test and culture. Noninvasive serological tests are useful as a screening test for H. pylori infection. The aim of this study was to evaluate the performance of a rapid office-based serologic test, using immunochromatography ICM, and the immunoblotting for the diagnosis of H. pylori infection in Thai children. Eighty-two symptomatic children, 30 boys and 52 girls (mean age 9.2+/-3.8 years; range, 1.2-16.0 years) who had no previous treatment for H. pylori underwent upper endoscopy. Biopsies were obtained from the gastric body and antrum for histopathology and rapid urease test. Serum samples collected from all patients were tested for H. pylori IgG antibodies using ICM (Assure H. pylori Rapid Test, Genelabs Diagnostics, Singapore). Immunoblotting (HelicoBlot 2.1, Genelabs Diagnostics, Singapore) was tested in sera of 75 patients to detect antibodies to specific antigens of H. pylori. Positive H. pylori status was defined as positive for both histology and rapid urease test. Of 82 patients, 25 (30.5%) were H. pylori positive, 56 (68.3%) were H. pylori negative and one was equivocal. ICM assay yielded a positive result in 24 of the 25 H. pylori-positive patients (96.0%) and 3 of the 56 H. pylori-negative patients (5.4%). The immunoblotting yielded a positive result in all of 22 H. pylori-positive patients (100%) and in 2 of the 52 H. pylori-negative patients (3.8%). Obtained ICM's sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 96.0, 94.6, 88.9, 98.1 and 95.1%, with immunoblotting 100.0, 96.2, 91.6, 100.0, and 97.3%, respectively. The immunochromatographic and immunoblot tests are non-invasive, reliable and useful for the diagnosis of H. pylori infection in Thai children.     

Low prevalence of Helicobacter pylori among symptomatic children from a hospital in Havana, Cuba

The aims of this study were to assess the prevalence of Helicobacter pylori infection and to introduce a new algorithm to improve its diagnosis in Cuban symptomatic children. One hundred and thirty-three consecutive children with upper gastrointestinal symptoms were studied. Patients were endoscoped and antral biopsies were obtained for rapid urease test (RUT), culture and histology. Prevalence of H. pylori infection was 30.8%. No statistical differences were found concerning demographic, socio-economic factors or chief clinical complaints, between H. pylori-positive and negative children, except for haematemesis, which was significantly higher in infected children (p?=?0.003). Histologically, there was statistical association between moderate chronic gastritis in infected children (p?=?0.04). Culture and RUT had the highest specificity and sensitivity, respectively. The prevalence of H. pylori infection in Cuban symptomatic children is similar to the one observed in developed countries. Culture and RUT is a useful combination to diagnose H. pylori infection in paediatric patients.     

Helicobacter pylori culture and antimicrobial susceptibility from pediatric patients in Michigan

BACKGROUND: We recently observed a high failure rate in the eradication of Helicobacter pylori infection in children with 2-week triple therapy using lansoprazole, amoxicillin and clarithromycin. We performed a prospective evaluation of antral biopsies of all children subsequently diagnosed with H. pylori gastritis for culture and antimicrobial susceptibility assessment. METHODS: All children with antral nodularity and/or an elevated anti-H. pylori IgG titer underwent antral biopsies for histology, urease test and culture while undergoing an upper endoscopy for routine indications. All positive cultures were tested for antimicrobial susceptibility by E-test for clarithromycin, amoxicillin, tetracycline and metronidazole. RESULTS: Thirty-one children (16 male, 15 female) between 2 and 19 years of age were diagnosed with H. pylori gastritis by histology. However, culture was positive in only 22 of 31 (71%) patients. The E-test in vitro antimicrobial susceptibility testing revealed that 95.6% of the isolates were susceptible to amoxicillin, 59% to clarithromycin and 54.6% to metronidazole. There was no resistance to tetracycline. CONCLUSION: Evaluation of antibiotic resistance profiles from pediatric patients from different geographic areas can help in optimizing therapeutic regimen to prevent treatment failures. Metronidazole and clarithromycin resistance is much higher in our pediatric population than reported in adults and could be a major contributor to failure of H. pylori eradication.     

Hp感染儿童胃十二指肠粘膜IL-8及IL-8 mRNA的研究

目的　检测Hp感染儿童胃、十二指肠粘膜中IL 8及IL 8mRNA的变化 ,从蛋白和分子水平探讨Hp对细胞因子IL 8的影响 ,以及IL 8在Hp相关性胃十二指肠疾病中的作用。方法　胃镜下取胃窦及十二指肠粘膜活检标本 ,用ELISA法和RT PCR半定量法测定胃及十二指肠粘膜中IL 8的含量和IL 8mRNA的表达量。结果　Hp阳性者胃粘膜IL 8为 2 4 66～ 177 77pg/mg ,IL 8mRNA为2 3 7～ 4 99;Hp阴性者胃粘膜IL 8为 2 94～ 12 98pg/mg,IL 8mRNA为 0 0 5～ 0 44 ;差异有显著意义(t分别为 12 3 4和 2 9 2 9,P <0 0 1)。Hp阳性者十二指肠粘膜IL 8为 12 98～ 177 77pg/mg ,IL 8mRNA为 1 2 2～ 1 80 ;Hp阴性者十二指肠粘膜IL 8为 2 0 4～ 10 43pg/mg ,IL 8mRNA为 0 0 1～ 0 2 3 ;差异有显著意义 (t分别为 7 18和 3 7 2 0 ,P <0 0 1)。活动性胃炎胃粘膜IL 8为 12 98～ 177 77pg/mg,IL 8mRNA为 0 5 1～ 4 99;非活动性胃炎胃粘膜IL 8为 2 0 4～ 10 43pg/mg,IL 8mRNA为 0 0 1～ 0 44 ;差异有显著意义 (t分别为 10 66和 18 62 ,P <0 0 1)。活动性胃炎十二指肠粘膜IL 8为 5 2 8～ 47 76pg/mg ,IL 8mRNA为 0 2 3～ 1 87;非活动性胃炎十二指肠粘膜IL 8为 3 19～ 8 14pg/mg,IL 8mRNA为0 0 1～ 0 2 0 ;差异有显著意义 (