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.     

Increased gastric juice leukotriene B4, C4 and E4 concentrations in children with Helicobacter pylori colonization

During recent years, the role of inflammatory lipid mediators in the pathophysiology of Helicobacter pylori (H. pylori) infections has been investigated in several studies. The concentrations of leukotrienes (LTs) in gastric juice from H. pylori positive (n = 13) and negative (n = 18) children with recurrent abdominal pain were studies in order to determine whether these lipid inflammatory mediators are involved in local and systemic biological actions. Gastric juice samples and biopsy specimens of mucosa were obtained endoscopically from 31 patients with recurrent abdominal pain for assessment of LTs and histopathological examination. In this study, all children with recurrent abdominal pain were investigated by rapid urease test and histological assessment for H. pylori colonization. Leukotriene levels were measured by high performance liquid chromatography (HPLC) and radioimmunoassay (RIA) in gastric juice samples. Gastric juice LTB4, LTC4, and LT4 levels were significantly higher in patients with H. pylori colonization than in children without H. pylori colonization. These results indicate that increased gastric content of proinflammatory mediators (LTB4, LTC4, and LT4) may be related to the pathogenesis of H. pylori-associated gastritis.     

Helicobacter pylori - dependent intragastric urea biodegradation in children: Diagnostic and pathogenetic importance

Abstract The objective of the present work was to study the relationship between intragastric urea hydrolysis generated by Helicobacter pylori urease and acid-peptic disease in childhood. Intragastric urease activity was examined by urea and ammonia concentration measurement in gastric juice in 91 children with upper abdominal complaints. Helicobacter pylori infection was detected from 70 (76.9%) of 91 patients, including all of the 15 subjects with peptic ulcer disease. Helicobacter pylori -related gastritis in children was associated with a decrease of urea and an increase of ammonia in gastric juice ( P < 0.001) in comparison with H. pylori-negative children. The gastritis score was correlated with the concentrations of urea and ammonia in the gastric juice of patients infected with H. pylori. There was a significant correlation between the histologically detected dissemination of organisms and gastric ammonia levels. Similar results were obtained concerning correlation between gastric juice ammonia and anti- H. pylori specific immunoglobulin G versus highly purified antigen of H. pylori containing urease. Present findings prove that H. pylori plays an essential role in the pathogenesis of gastritis and that ammonia is one of the main pathogenic factors of acid-peptic disease.     

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.     

PCR技术在儿童幽门螺杆菌感染中的应用

目的 建立一套适合儿童幽门螺杆菌感染的PCR检查方法，了解儿童幽门螺杆菌感染的可能途径。方法 对37例4～14岁患儿采用聚合酶链反应检测胃粘膜、胃液和唾液中的幽门螺杆菌，并作胃粘膜快速尿素酶、病理W—S银染色及细菌培养。结果 37例患儿中尿毒酶、病理W—S银染色、细菌培养、胃粘膜PCR、胃液PCR和唾液PCR的检出率分别为35．14％、40．54％、35．14％、45．95％、35．14％和5．40％；敏感性为68．8％、81．2％、81.3％、93．8％、81.3％、12．5％；特异性为90．5％、90．5％、100％、90．5％、100％、100％；2项或2项以上检出率阳性判断为幽门螺杆菌感染，37例患儿中阳性16例。结论 胃粘膜、胃液PCR方法同其他幽门螺杆菌检测手段相比幽门螺杆菌阳性检出率相似，PCR方法具有操作简便，特异性、敏感性高的优点，是诊断儿童幽门螺杆菌感染、判断药物疗效的有效检查手段。唾液PCR阳性率低可能与口腔缺乏特定的幽门螺杆菌生长环境有关，但也提示口-口传播是幽门螺杆菌感染的可能途径。     

胃液实时聚合酶链反应检测儿童幽门螺杆菌及宿主基因型的临床研究

目的探讨胃液实时聚合酶链反应(real-time PCR)检测儿童幽门螺杆菌(HP)感染、克拉霉素敏感性和宿主CYP2C19基因代谢型方法的准确性,旨在寻求一种方便、快速、准确检测儿童HP感染,克拉霉素敏感性和CYP2C19基因代谢型的方法。方法选取2013年7月至2014年11月北京儿童医院消化科123例13C呼气试验检查阳性的胃炎或消化性溃疡患儿进行电子胃镜检查,胃镜下取胃黏膜并收集胃液标本。从胃液中提取DNA,然后通过聚合酶链式反应(PCR)扩增Rnase P酶和cag H以检测幽门螺旋杆菌的存在。通过PCR限制性片段长度多态性(PCR-RFLP)分别检测HP23SrRNA和宿主CYP2C19基因代谢型。研究共利用5对引物和9条探针进行HPcag H基因和23SrRNA基因,以及人Rnase P基因和CYP2C19*2、CYP2C19*3基因检测。将胃液结果与胃黏膜活检标本HP培养和E-test药敏试验及CYP2C19基因代谢型检测结果进行比较分析。结果以胃黏膜HP培养、E-test药敏试验及CYP2C19基因代谢型检测结果为金标准,胃液实时PCR检测HP感染诊断敏感度为100%...     

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.     

PCR检测慢性胃炎患儿胃液中幽门螺杆菌DNA

目的检测慢性胃炎儿童胃液中幽门螺杆菌DNA，探讨其在临床诊断中的实用价值。方法应用PCR检测胃液中幽门螺旋菌DNA，应用Warthin-Starry银染色检测胃粘膜组织中的幽门螺旋菌。结果胃炎组与非胃炎组比较，敏感性为75.0％，特异性为96．2％，两组有显著性差异（P＜0．01）。PCR与Warthin－Starry银染色比较，PCR优于Warthin—Starry银染色法。结论PCR检测患儿胃液中的幽门螺旋菌DNA，具有敏感、快速、特异、高效等优点，是基因水平上检测幽门螺旋菌一项新技术，用于慢性胃炎的早期诊断，具有较好的实用价值，值得推广应用。     

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.     

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.     

Characteristics and prevalence of Helicobacter heilmannii infection in children undergoing upper gastrointestinal endoscopy.

BACKGROUND: Helicobacter heilmannii, described in 1983 as a new cause of chronic gastritis, has been reported rarely in children. The purpose of this study was to determine the clinical characteristics and the prevalence of H. heilmannii infection, in comparison with Helicobacter pylori infection in children undergoing upper digestive endoscopy. METHODS: Diagnosis of H. heilmannii was based on its morphologic characteristics in gastric biopsy specimens (two from the antrum, one from the fundus), whereas H. pylori infection was defined by histology and/or culture (one specimen from the antrum, one from the fundus). Respective prevalences of H. heilmannii and H. pylori were calculated in 518 patients studied prospectively who underwent systematic biopsies. RESULTS: The prevalence of H. pylori was 8.9% (46/518) and increased with age (from 2% before 3 years of age to 18% after 10 years). On the contrary, the prevalence of H. heilmannii infection was low, 0.4% (2/518), and no different from that published in adults. After completion of the study period, a third H. heilmannii-infected child was diagnosed. Characteristics of H. heilmannii infection could be studied in these three children 5, 9, and 14 years old. Two of three had abdominal pain and one had dysphagia. Nodular gastritis was observed at endoscopy in two children. H. heilmannii chronic active gastritis (n = 3) was localized in the antrum, associated with an interstitial infiltrate, and could not be distinguished from H. pylori gastritis (n = 46). CONCLUSION: Clinical characteristics, endoscopic features and gastric histopathology did not allow H. heilmannii to be distinguished from H. pylori gastritis in our pediatric population. H. heilmannii infection should be considered and carefully looked for during histologic examination of gastric specimens in cases of H. pylori-negative gastritis.     

Helicobacter pylori infection and chronic gastritis: clinical, serological, and histologic correlations in children treated with amoxicillin and colloidal bismuth subcitrate

Twenty-three children with Helicobacter (Campylobacter) pylori-associated chronic gastritis are reported. Family history of peptic disease, previous digestive procedures, and nonspecific epigastric pain were the most frequently encountered clinical features. Antral nodularity at endoscopy and histologic evidence of follicular gastritis were characteristic morphological aspects. Rapid urease tests suggested the diagnosis in 90% of patients. Significant increases of serum IgG and IgA against Helicobacter pylori allowed the identification of infected children with 95% cumulative sensitivity. Treatment with amoxicillin and bismuth subcitrate eradicated the infection and improved gastritis in 13 of 19 children. These findings provide further evidence for the etiologic role of Helicobacter pylori in chronic antral gastritis in children.     

Immunohistochemical detection of Helicobacter pylori infection in gastric biopsies of urea breath test-positive and -negative pediatric patients

Helicobacter pylori (H. pylori) is a common cause of gastritis in both children and adults, and its incidence increases every year. The aims of this study were to evaluate the histopathologic features of H. pylori gastritis and to compare immunohistochemical with histochemical [hematoxylin-eosin (HE) and Giemsa] staining of gastric biopsy specimens for the detection of H. pylori infection from urea breath test (UBT) (-) and UBT (+) children. Seventy-eight gastric biopsies from pediatric patients who were administered UBT were included in this study. Gastric biopsy specimens were evaluated histopathologically and graded according to the Sydney system. HE, Giemsa and immunohistochemical staining was performed for the identification of H. pylori. The frequency of H. pylori gastritis was higher in the antrum than corpus. All biopsies with H. pylori colonization showed chronic inflammation with activity. By using immunohistochemical method, coccoid forms of H. pylori and spiral bacteria with low density were observed easily. With histochemical staining, 1/10 (10%) UBT (-) biopsies were H. pylori (+), while with immunohistochemical staining, 3 of the biopsies from UBT (-) patients were found to be H. pylori (+). Biopsies from 65 of 78 (83.3%) UBT (+) patients were H. pylori (+) with histochemical staining, but only 53 of these biopsies were found to be H. pylori (+) immunohistochemically. We conclude that immunohistochemical staining is more specific than histochemical staining and UBT for the detection of H. pylori infection.     

CagA seropositivity and the severity of Helicobacter pylori infection in dyspeptic children

AIM: To assess the incidence of cagA (cytotoxin-associated protein) and to evaluate its correlation with endoscopic-histologic findings and with eradication rate in a series of children affected by Helicobacter pylori (H. pylori) gastritis. METHODS: Fifty consecutive H. pylori gastritis children (27M; median age 10 y and 11 mo) were tested for IgG cagA protein (Western Blot technique). Pretreatment H. pylori infection was assessed on the grounds of endoscopic antral biopsy specimens by means of rapid urease test and histologic examination (Giemsa staining). All the children were treated with omeprazole (1 mg/kg/d), clarithromycin (15 mg/kg/d) and amoxycillin (50 mg/kg/d) for 2 wk. According to universally accepted clinical practice, outcome of treatment was assessed by 13C urea breath test at least 6 wk after the end of therapy. RESULTS: Thirty-five children (70%) were seropositive to cagA+ protein (median age 11 y and 1 mo). Endoscopic findings of cagA+ patients were similar to those of cagA- patients. In cagA seropositive patients the severity of histologic gastritis was higher (p < 0.05) and the granulocytic infiltration more marked (p < 0.01) than in seronegative ones. In cagA+ children, H. pylori eradication rate was significantly lower (p < 0.02). CONCLUSIONS: cagA testing may be of useful clinical interest because its positivity can imply a more severe gastritis and a lower susceptibility to eradication treatment.     

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。     

消化性溃疡患儿唾液,胃液和血清中表皮生长因子含量

目的了解表皮生长因子（ＥＧＦ）与小儿消化性溃疡病的发生、愈合之间的关系，探讨小儿溃疡病的可能发生机理。方法采用放射免疫法测定了５５例溃疡与５１例慢性胃炎患儿的唾液、胃液和血清中ＥＧＦ的含量。结果消化性溃疡患儿在溃疡活动期时，唾液和胃液中的ＥＧＦ水平明显低于慢性胃炎组，而在溃疡愈合期时，唾液、胃液、血清中ＥＧＦ水平显著升高，尤为胃液。结论消化性溃疡患儿存在ＥＧＦ的分泌异常，ＥＧＦ分泌水平的变化可能与消化性溃疡的发生与愈合有一定关系。     

幽门螺杆菌相关性胃十二指肠疾病患儿MMP-7基因多态性研究

目的 研究基质金属蛋白酶-7(MMP-7)基因启动子多态性与儿童幽门螺杆菌(H-pylori)相关性慢性胃炎、十二指肠溃疡的易感性和临床特征的关系.方法 提取100例慢性胃炎、32例十二指肠溃疡和102例健康对照组儿童的外周血或胃黏膜基因组DNA,采用聚合酶链反应-限制性片段长度多态性技术(PCR-RFLP)和测序方法检测其MMP-7基因-181A/G多态性位点的基因型,分析该基因的基因型和等位基因频率在病例组和对照组人群中的分布及基因型分布与临床病理特征的关系,采用反转录-聚合酶链反应(RT-PCR)方法检测各组胃黏膜MMP-7 mRNA的表达.结果 MMP-7基因-181A/G多态性位点的基因型和等位基因频率在病例组和对照组人群中的分布差别无统计学意义,亦与H.pylori易感性无关.MMP-7基因-181A/G多态性不影响MMP-7 mRNA在胃黏膜中的表达,且与胃窦黏膜慢性炎症程度无相关性.结论 MMP-7基因-181A/G多态性与儿童慢性胃炎和十二指肠溃疡发生的易感性无关.     

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.     

Plasma and gastric juice levels of prostaglandins in critically ill children.

The levels of prostaglandin (PG) E2 and 6-keto-PGF1 alpha (stable metabolite of prostacyclin) in plasma and gastric juice were determined in 113 critically ill children and adolescent, and compared to those registered in a plasma control group of 24 children and a gastric juice control group of 15. The gastric juice concentration of PGE2 is our patients [9.2 +/- 3.1 (SEM) pg/ml] was significantly lower (p = 0.001) than in the control group [81.1 +/- 18.1 (SEM) pg/ml]. There were no differences in plasma levels of PGE2 and plasma gastric juice levels of 6-keto-PGF1 alpha between the patients and the control groups. Children who died had lower plasma levels of PGE2 [6.2 +/- 2.2 (SEM) pg/ml] and gastric juice levels of PGE2 [2.3 +/- 0.8 (SEM) pg/ml] than the survivors (p less than 0.05). The gastric juice concentration of PGE2 was also lower in children who suffered important upper gastrointestinal bleeding, although the difference did not reach statistical significance.     

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.