PubMed Health⌕ Search

Biomedical subjects

Anthony Axon

Publications and source records attributed to Anthony Axon.

10 recordsLinked to original sources
PubMed2006

Symptoms and diagnosis of gastric cancer at early curable stage.

Five-year survival of gastric cancer is 10% in Western countries compared with over 50% in Japan. This is because the disease is not identified in the West until later in its evolution. T1 cancer has an excellent prognosis, but most of the patients either have no symptoms or complain of long-standing, non-specific dyspepsia; alarm symptoms, when identified, usually indicate that the cancer is already inoperable. Early gastric cancer is infrequently diagnosed in the West because the low prevalence of gastric cancer means that endoscopists do not search with the same diligence as they do in Japan. A further barrier is the widespread prescription of proton pump inhibitors that heal malignant ulcers and diminish symptoms, thus rendering them more difficult to identify clinically and endoscopically. An improvement in diagnosis may be achieved by newer endoscopy technology which enables cancers to be identified more easily, or by an inexpensive screening test to select patients with extensive gastric atrophy, thereby identifying those at risk who can then be screened endoscopically.

Endoscopy, Gastrointestinal↗
PubMed2006

Helicobacter pylori: what do we still need to know?

Helicobacter pylori is a common gastric infection that causes serious complications in a minority of individuals. A great deal is known about the disease, but many unanswered questions remain. Among these, perhaps the most enigmatic is that we do not know how the organism is transmitted. We are uncertain why the prevalence of the disease is falling within the developed population. There is still debate as to its relationship with gastroesophageal reflux disease. It is unclear why there are differences in the international incidence of gastric cancer. Similar uncertainties relate to the reasons why the complications of H. pylori infection have changed over time. In this article, I have hypothesized that a number of these unanswered questions may be related to a putative increase in gastric acid secretion that may have taken place during the past 200 years. To date, there is little confirmatory evidence for this, and it remains a fascinating area that merits more scientific research.

Gastric Acid↗
PubMed2005

Association between Helicobacter pylori infection and adult height.

OBJECTIVES: A cross-sectional survey was performed to evaluate the association between H. pylori and adult height. METHODS: H. pylori infection was assessed using a 13C-urea breath test and height measured by a research nurse using a stadiometer in participants between the ages of 40-49 years. RESULTS: Height was measured in 2932/3682 participants that attended and were evaluable. H. pylori infected women were 1.4 cm shorter than uninfected women (95% confidence interval, CI = 0.7-2.1 cm) and this statistically significant difference persisted after adjusting for age, ethnicity, childhood and present socio-economic status (H. pylori positives 0.79 cm shorter; 95%CI: 0.05-1.52 cm). H. pylori positive men were 0.7 cm shorter than uninfected men but this did not reach statistical significance (95% CI: -0.1-1.5 cm). CONCLUSION: Although H. pylori infection is associated with reduced adult height in women, this maybe due to residual confounding.

Adult↗
PubMed2003

Role of bacterial overgrowth in the stomach as an additional risk factor for gastritis.

Gastric bacteria can either be ingested or ascend from the distal bowel; however, their survival is usually limited by gastric acidity and motility. A reduction in gastric acid can result in bacterial overgrowth in the stomach and proximal small bowel, and the number of organisms rises as the intragastric pH rises. The increased risk of noncardia gastric cancer seen in patients with hypochlorhydria may be explained by an excess of nitrites and N-nitroso compounds (NOCs). These compounds are found in the diet of populations with a high gastric cancer risk, but can also be produced by the organisms that exist in the hypochlorhydria stomach. It has long been hypothesized that nitrites and NOCs act as one of the triggers in the atrophy-metaplasia-dysplasia-carcinoma path. However, although indirect data have linked the premalignant changes of metaplasia and dysplasia to NOCs, direct measurement of gastric nitrites and NOCs has not confirmed such a link. The role of Helicobacter pylori in bacterial overgrowth is mainly as a cause of hypochlorhydria resulting from atrophic gastritis, leading to a reduction in the parietal cell mass. Acid-suppressing drugs can result in bacterial overgrowth and increased nitrites and NOCs, although there is no current evidence for an increased risk of gastric cancer in patients taking them. One explanation is that the stomach appears to be colonized by different organisms than those in patients with hypochlorhydria for other reasons. There is some evidence that bacterial overgrowth per se can cause gastric inflammation in mice; however, although in humans the degree of gastric inflammation is greater when overgrowth is more prominent this may simply reflect the greater degree of hypochlorhydria in patients with a more severe H pylori-induced inflammation.

Acetaldehyde↗
PubMed2003

Ethical issues in the management of Helicobacter pylori infection.

Medical ethics are not absolute; they change according to social attitudes, technological advances and alterations in the doctor/patient relationship. The discovery of Helicobacter pylori highlighted entrenched attitudes in academia and the pharmaceutical industry that were not always appropriate. The explosion of research that followed was ethically controlled by local research ethics committees and the system of peer review and editorial responsibility. Now that effective treatments are available, the control arm in trials of new therapy should be either placebo (giving the option of effective treatment later) or a first-line treatment; mono and dual therapy should not be employed because of the risk of inducing bacterial resistance. Ethical issues that still remain include whether always to test patients for H pylori at endoscopy and what information should be given when they test positive. The most important issue is the approach of the medical profession to the high death rate carried by H pylori infection. Peptic ulcer and gastric cancer together account for a large number of deaths worldwide, and the medical profession and public health services have not yet grappled with this problem, neither advocating universal testing and treatment nor funding or research to determine whether this approach would be effective.

Ethics, Medical↗
PubMed2002

Management of uninvestigated dyspepsia: review and commentary.

Up to 40% of individuals complain of dyspepsia but only 25% of these present to their general practitioner. If symptoms have been present for a relatively short period the majority can be managed by reassurance and symptomatic treatment. Those with a longer history require empirical treatment with more powerful medication, endoscopy, testing for Helicobacter pylori, or a combination of these approaches. There is some debate about whether the treatment of Helicobacter pylori infection is an appropriate strategy for patients with dyspepsia. It is the general practitioner who determines how the uninvestigated patient with dyspepsia will be managed because those referred to hospital usually undergo endoscopy at an early stage.

Dyspepsia↗
PubMed2002

Ethical considerations in gastroenterology and endoscopy.

Previously doctors decided what was right or wrong in medicine, today our individual freedom is more limited. External influences including the human rights act, government initiatives, management protocols, professional guidelines, multi-disciplinary decision-making and financial restrictions intervene between the doctor and the patient. Furthermore the move away from paternalism in the doctor-patient relationship to patient empowerment (informed consent) has put patients in charge of their medical destiny. Increased public expectations leading to health screening, genetic profiling and treatment of unwanted physiological changes mean that doctors now manage healthy patients for 'potential' or 'virtual' disease. This implies a greater ethical burden than treatment of the sick. Finally, death is no longer regarded by many as a physiological process, but a consequence of disease. The investigation and management of patients with incurable conditions can lead to difficult ethical dilemmas. Gastroenterology and endoscopy generate specific ethical problems which among others include training in endoscopy, percutaneous endoscopic gastrostomy placement, informed consent and live endoscopy demonstrations. This article addresses some of these issues in order to draw attention to potential difficulties in modern ethical practice. It should be read in conjunction with the other publications stemming from the 1st Symposium on Ethics in Gastroenterology and Endoscopy, Kos, June 2002.

Endoscopy, Gastrointestinal↗
PubMed2002

An introductory course for training in endoscopy.

Endoscopy practice must respect the ethical aspects of medicine, and the principles of humanism must be reinforced when teaching endoscopy. A well-organized, structured training is essential if we are to ensure that procedures are performed in a safe and effective manner. The most difficult period of training is with the novice endoscopist, so we recommend the introduction of a structured pre-endoscopy training curriculum. This should ideally include introductory lectures and courses, the use of didactic videotapes and training in endoscopy on a computer-based simulator. We also advocate 'train the trainers' international courses to encourage a uniform approach to the teaching of endoscopy. Their aim will be to educate skilled endoscopists in the principles of teaching, which should be thoroughly grounded in the ethics of our profession.

Curriculum↗