Indigestion Investigations

Endoscopy and other investigations to look for the cause of indigestion

The most common test is an upper gastrointestinal endoscopy (oesophagogastroduodenoscopy, OGD, endoscopy). In this test, a flexible telescope is passed via the mouth down the oesophagus and into the stomach. The telescope then passes beyond the stomach into the duodenum (the first part of the small intestine). The test is either undertaken with short-acting intravenous sedation or, in many cases, with no sedation but some local anaesthetic throat spray to numb the gag reflex. About half of patients choose to have sedation to make the test more comfortable but, because this then means staying longer and needing someone to collect you, many prefer to have the test without sedation. It is a very quick test, usually taking no more than 10 minutes once started. Biopsies (small samples of the lining) are taken at the time of the test. The procedure is undertaken as a day case and, if having sedation, involves being at the hospital for about 2 hours.

The need for endoscopy depends partly on the symptoms and partly on an individual’s age. In younger people, the chances of any serious problem being found is low and endoscopy is therefore needed less often. A trial of treatment will often be done initially and, perhaps, a blood or stool test to detect Helicobacter infection (see below). If treatment fails, then endoscopy may become necessary. In older individuals, and in those with any of the alarm symptoms above, endoscopy is more than likely to be recommended.

Other tests include an ultrasound of the abdomen which is the simplest test to look for gall stones and at the other structures in the upper abdomen such as the liver, spleen, kidneys and pancreas. Occasionally, other tests might include a barium swallow or meal where xray contrast is swallowed to give images of the upper intestine, or a CT scan of the abdomen, which is sometimes used in addition to ultrasound, to image the structures surrounding the stomach.

Peptic ulcers and Helicobacter pylori infection

Until around 20 years ago, peptic ulcers (duodenal and gastric ulcers) were only known to be related to excessive acid and other factors, especially stress were thought to be an important cause. We now know that stress is not the cause of ulcers, although this myth still lives on. In the early 80’s, Barry Marshall and colleagues, proved that spiral bacteria, noticed in the stomach for years before, were the cause of nearly all duodenal ulcers and a majority of gastric ulcers. The bacteria, Helicobacter pylori (Hp), infects the stomach causing chronic inflammation if the stomach lining (gastritis) usually without symptoms. In most people, this causes gastritis affecting the whole of the stomach, including the acid producing areas, and therefore acid levels gradually fall. This pattern of Hp gastritis will lead to gastric ulcers in a small number of people and, over many years, is associated with cancer of the stomach (because low stomach acid allows bacteria to build up in the stomach with knock-on effects that harm the stomach lining). In a smaller number of people, Hp causes only gastritis in the last third of the stomach (the antrum) leaving a normal acid producing area (the body or corpus). This is key to why Hp can infect the stomach but cause an ulcer in the duodenum. Gastritis in the antrum increases the stimulus to acid production in the body of the stomach which in turn leads to more acid than usual passing out of the stomach into the duodenum (the next part of the intestine). Here, the acid leads to areas of the lining which become weakened which, in certain situations, will then develop into an ulcer.

So, nearly all duodenal ulcers are due to H.pylori infection in the stomach and the treatment is to use a combination of acid lowering medicine and antibiotics (“triple therapy”) to cure the infection. This in turn will heal the ulcer.

Importantly, whilst H.pylori remains common worldwide, it is comparatively rare in people born in the UK in the last 3 or 4 decades. As a result, ulcers are not so common and indeed, cancer of the stomach, has also become much rarer as rates of H.pylori have declined. The main cause of ulcers is now due to medicines which weaken the stomach or duodenal lining such as aspirin and anti-inflammatory drugs (NSAID’s). Moreover, in Western populations, the lack of H.pylori infection and therefore “healthy” acid production has been combined with a steady rise in the average weight and abdominal girth amongst the population leading to a huge increase in rates of acid reflux (gastro-oesophageal reflux). This is important not just because lots of people get these symptoms, but, importantly, there has also been a rapid rise in rates of oesophageal cancer as a result of chronic acid reflux.

Gastro-oesophageal reflux

As above, symptoms of reflux are very common amongst people in western societies. In most cases, these symptoms, for example heartburn, are temporary and due to an obvious episode of dietary indulgence or, say, during pregnancy. In these cases, little action is needed other than taking antacids (rennies, gaviscon etc) to relieve the symptoms and realising that eating that extra portion late at night is going to have consequences! In some cases, however, reflux symptoms are more severe or longer lasting and therefore need assessment.

In general, doctors are concerned about new symptoms that stay for a few weeks, in people aged over 50 years, or if there are any worrisome features such as vomiting blood, anaemia (low blood count), black stools, difficulty swallowing or loss of weight. All of these would merit investigation, with endoscopy, as above, being the procedure of choice. In individuals below 50 years, without worrisome symptoms, doctors would usually try some acid-reducing medicine for say 4 weeks and if the symptoms persist or relapse after stopping the treatment, then consider investigation.

Why have an endoscopy for reflux symptoms?

There are two main concerns about persisting or recurring reflux symptoms that make endoscopy important. Firstly, there is the need to rule out other diagnoses, particularly cancer. This is especially the case in those aged over 50 but, even in this group, the chances of a cancer are very low if no worrisome symptoms are present. Secondly, and more commonly, there is the need to assess whether or not there is inflammation present in the lower oesophagus (rather than just symptoms). This is called reflux oesophagitis and has a characteristic appearance at endoscopy where the effects of acid eroding the lining of the lower oesophagus can be clearly seen. If this is present, treatment with drugs to reduce acid (mainly proton pump inhibitors [PPI’s] such as omepraolze, lansoprazole etc) are very important. Cancer of the lower oesophagus develops on a background of chronic reflux oeosphagitis which over time leads to a change in the lining called Barrett’s oesophagus. One aim of endoscopy therefore is to identify and treat those with oesophagitis in order to prevent subsequent risk of Barrett’s and oesophageal cancer. The ability to prevent oesophageal cancer in this way has not been proven but makes absolute sense form what we know about the background in which cancer develops. Many involved in the field recommend the concept of a “once in a lifetime endoscopy” in those with a tendency to reflux basically to look for oesophagitis and characterise risk. Those with oesophagitis should be treated with courses of PPI’s to heal the lining and should often remain on longterm treatment. Those without oesophagitis can be advised to use more “on demand” treatment with PPI’s when and if symptoms occur.

 

How do I get treatment?

To get further information or treatment, please contact one of our consultants at The London Bridge Digestion centre, on:

tel: +44 (0) 20 7403 3814
email:
admin@londondigestion.co.uk