Helicobacter pylori infection and genetic polymorphisms for cancer-related genes in gastric carcinogenesis

The development of gastric cancer is a multistep process that is multi-factorial. An association with the Helicobacter pylori infections, gastric atrophy and gastric cancer has received recent attention. The objective of this study was to elucidate the risk factors for gastric cancer by using molecular epidemiological techniques for genetic susceptibility, gastric atrophy and serum markers including H pylori infection. We used an age- and gender-matched case-control study, where patients with benign gastric lesions were the controls. Low serum pepsinogen I levels (cut-off < 50 ng/mL) and low pepsinogen I/pepsinogen II ratios (cut-off < 3.0) were significantly associated with the risk of gastric cancer (odds ratio [OR] = 3.53: 95% confidence interval [CI] = 2.46-5.09 and OR = 4.73: 3.26-6.88, respectively). However, seropositivity of serum immunoglobulin G (IgG) antibody against H pylori (OR = 1.09: 0.74-1.61) was not associated with gastric cancer, even when analyzed by age greater than or less then 50 years. Specific genotypes of the cytochrome p450 2E1 (CYP2E1) RsaI polymorphism and glutathione-S-transferase (GST) M1 gene deletion were determined but were not associated with gastric cancer; however, a Lmyc genetic polymorphism was associated with gastric cancer (OR = 1.55: 1.03-2.34). Therefore, in this Japanese study, atrophic mucosal change, indicated by serum pepsinogen levels, is a possible risk factor for gastric cancer.     

Helicobacter pylori infection

CHROMagar, a chromogenic differential culture medium, is claimed to facilitate the isolation and presumptive identification of certain clinically important yeast species, e.g., Candida albicans. This study evaluated the cost-effectiveness and time advantage of using it in comparison with Sabouraud dextrose agar (SDA). Three possible pathways, each of which included the use of one or both media, were compared in a routine laboratory. A total of 21 yeast isolates was cultured from 298 clinical samples from neutropenic and AIDS patients. An overall sensitivity of 95.2% was observed for each medium and primary isolation on CHROMagar was found to be 100% sensitive and 100% specific for C. albicans. For identification purposes, after initial culture the use of CHROMagar provided the most economical and least time-consuming method. Direct inoculation on to CHROMagar is recommended for blood cultures when yeast cells are seen on microscopy and where early appropriate therapy is imperative.     

Helicobacter pylori and stomach cancer]

The neoplasms and gastric mucosa colonization with Helicobacter pylori was studied in 40 stomachs resected for expansive (n = 20) and infiltrative (n = 20) carcinoma using Giemsa staining histological sections, histochemical reactions to oxyreductase, and urease test. In expansive carcinoma of the stomach, H. pylori was identifiable both in the tumour and surrounding gastric mucosa in 70 per cent of cases; infiltrative carcinoma appeared to be associated with gastric mucosa H. pylori in 80 per cent, whereas tumour H. pylori were recordable in 30 per cent of cases, which fact is dependent upon the histological structure of carcinoma. The role H. pylori plays in cancerogenesis is discussed.     

Helicobacter pylori infection in children

BACKGROUND: Although immigrants to the United States are usually ethnic minorities and socioeconomically disadvantaged, foreign-born women generally have lower rates of low birth weight infants than do US-born women. OBJECTIVE: To measure the relationship between maternal birthplace, ethnicity, and low birth weight infants. DESIGN: Retrospective cohort study of birth certificate data. SETTING: California, 1992. SUBJECTS: Singleton infants (n = 497 868) born to Asian, black, Latina, and white women. MAIN OUTCOME MEASURES: Very low birth weight (500-1499 g), moderately low birth weight (1500-2499 g), and normal birth weight (2500-4000 g, reference category). RESULTS: Foreign-born Latina women generally had less favorable maternal characteristics than US-born Latinas, yet foreign-born Latina women were less likely to have moderately low birth weight infants (odds ratio, 0.91; 95% confidence interval, 0.86-0.96) than US-born Latinas after adjusting for maternal age, education, marital status, parity, tobacco use, use of prenatal care, and gestational age. While foreign-born Asian women generally had a less favorable profile of maternal characteristics than US-born Asians, there was no statistically significant difference in the odds of very low birth weight or moderately low birth weight infants between foreign- and US-born Asian women. Foreign-born black women had more favorable maternal characteristics than US-born women, but there was no significant nativity difference in very low birth weight or moderately low birth weight between foreign- and US-born black women after adjusting for maternal and infant factors. CONCLUSIONS: The relationship between maternal birthplace and low birth weight varies by ethnicity. Further study is needed to understand the favorable pregnancy outcomes of foreign-born Latina women.     

Helicobacter pylori infection in congestive gastropathy

This report describes a family who demonstrated anomalies of tooth form and eruption of the lower second premolar. Observation of the second premolars remaining in the mother's and father's dentitions included ectopic eruption with impaction and substantial spacing between the first and second premolars. Four siblings were also examined--three boys aged 15, 14 and 12 years, and one girl aged 11 years. Anomalies of the second premolar recorded in the males and female include: congenital absence, ectopic eruption with impaction, delayed eruption and spacing. Associated anomalies included: congenital absence of other permanent teeth and spacing. It appears that the defect in tooth form and eruption is of a genetic origin, affecting both males and females. The condition(s) did not appear to be associated with a syndrome and the human papilloma virus lesions noted in all family members were not considered to be related to the dental defects. This family demonstrated two anomalies of the lower second premolar: congenital absence and disturbance in tooth eruption. The question raised by this case report is whether these two anomalies are inherited as separate traits or whether failure of tooth eruption is a variation in expression of the same genetic factor that results in oligodontia.     

Treatment of Helicobacter pylori infection

The article presents information gained from a survey among Norwegian hospitals in March 1997 concerning their treatment of infections with Helicobacter pylori. Altogether 52 hospitals answered the questionnaire. A combination of proton pump inhibitors, metronidazole and clarithromycin was used by 59% as first choice and urea quick test (94%) and urea breath test (42%) as the primary diagnostic procedures, whereas serology was in little use (17%). Besides ordinary ulcer disease, indications for treatment were: ulcer induced by non-steroid anti-inflammatory drugs (79%), gastrooesophageal reflux (37%), non-ulcer dyspepsia (14%) and cancer prophylaxis (14%). The gastro group at the Department of Pharmacotherapeutics at the University of Oslo invited specialists from all health regions to discuss indications for treatment of H pylori, the diagnosis and the role of general practitioners. The extensive use of clarithromycin might be doubtful due to development of resistance. Indications for treatment of H pylori other than ulcer disease and mucosa associated lymphoid tissue lymphoma are still uncertain. Uncritical use of serological tests in primary care should be discouraged. At present there is no uniform strategy for the diagnosis and treatment of H pylori infection, and a coordinated strategy between general practitioners and specialists is needed.     

Treatment of Helicobacter pylori infection

Since acceptance of the association between Helicobacter pylori and peptic ulcer disease, eradication of H. pylori has become the standard of care in the treatment of peptic ulcer disease. Unfortunately, eradication therapy is no easy task, especially when one is faced with a myriad of drug combinations with varying degrees of efficacy and tolerability. The following is a review of the literature regarding the drugs and drug combinations used to eradicate H. pylori and their effectiveness both as single agents and in combination.     

Physiopathology of Helicobacter pylori infection

The gastric juice of Helicobacter pylori-infected individuals contains substantially higher levels of phospholipase A2 (PLA2) than that of individuals who are not infected. We present a new theory for how this H. pylori-induced PLA2 activity in gastric juice may play a major role in the development of peptic ulcer disease. When activated at neutral pH (pH 6.5-7.0), PLA2 may damage the surfactant-like, phospholipid-rich layer which constitutes an important part of the mucus barrier. Pepsin and other proteases, activated at low pH (pH 1.0-3.5), may then denature and cleave PLA2-exposed proteins. Peptic ulcers therefore tend to develop in regions exposed to changing luminal pH, such as the duodenal bulb when acid production is high or normal, or in the stomach when acid secretion is low.     

Helicobacter pylori infection in recurrent abdominal pain

The superior and inferior gemellus muscles were examined as to their forms and the patterns of nerve supply in 13 human cadavers (20 specimens). The superior gemellus muscle (Gs) was absent in 3 specimens, but showed no accessory slip or fusion with the internal obturator muscle (Oi). The nerve to the Gs originated from the nerve to the Oi (OiN) in 7, the nerve to the quadratus femoris muscle (QfN) in 4, or both in 6 specimens. The inferior gemellus muscle (Gi) was present in all, but fused with the Oi in 3 specimens. In one specimen, an accessory muscle bundle was observed between the Gi and Oi. The Gi always received branches from the QfN at its anterior surface, but received an additional nerve supply at its posterior surface from the OiN or the pudendal nerve in one specimen each, and the accessory bundle was supplied by a branch from the OiN at its posterior surface. In a well preserved specimen, a branch to the Gi from the QfN entered the Oi and communicated with the OiN after supplying and leaving the Gi. The frequency of the dual innervation of Gs by the OiN and QfN was 29.3%, but that of the Gi and Oi could not be determined, because of the occurrence of the fused part, the accessory bundle and nerve communication. There existed some gross anatomical differences between both gemelli muscles; they are considered to be parts of the internal obturator muscle in a broad sense.     

Gastric juice neopterin in Helicobacter pylori infection

Neopterin, a pteridine compound produced by macrophages activated by interferon-gamma, is widely used to assess the activation of cellular immunity. An elevation in serum or urinary neopterin reflects immune activation in many different disorders, including viral infections, cancer, autoimmune diseases or acute myocardial infarction, but less attention has been paid to neopterin concentration in other biological fluids. The aim of the present study was to examine neopterin concentration in gastric juice. An association with the presence of Helicobacter pylori, a bacterium linked to the most common disorders of upper digestive tract, was also investigated. Gastric juice was obtained at endoscopy from 61 patients. Neopterin was determined by a radioimmunoassay and the presence of H. pylori was examined by urease test. The macroscopic finding of bile in gastric juice was associated with significantly higher neopterin levels compared to patients where no bile was noted (15.5 +/- 15.6 vs. 2.1 +/- 3.0 nmol/l, P < 0.001). However, similar concentrations were observed in the H. pylori positive and H. pylori negative patients (7.6 +/- 12.0 vs. 11.1 +/- 14.9 nmol/l). Even in the absence of macroscopic bile contamination, no significant difference could be found between the infected and uninfected patients (2.3 +/- 3.2 vs. 1.3 +/- 1.9 nmol/l), and the patients with duodenal ulcer and normal findings (3.8 +/- 4.6 vs 1.6 +/- 1.9 nmol/l). The contamination of gastric juice with bile represents the limitation for the use of neopterin as a marker of immune activation in the gastric mucosa. Rather than an index of immune activation, gastric juice neopterin concentration represents a marker of duodenogastric reflux.