Which ONE of the following statements is TRUE regarding the aetiology of peptic ulcer disease (PUD)?
Answer: A: The most common cause of PUD is infection with H. pylori, accounting for 70–90% of ulcers. It is the major cause, or at least a cofactor, in the development of PUD, with 90–95% of patients with duodenal ulcers and 70% of those with gastric ulcers infected with H. pylori. Although H. pylori is commonly present in the mucosa of many people, only 10–20% of infected patients will develop PUD. Interestingly, the prevalence of H. pylori is lower in patients with complicated duodenal ulcers (bleeding or perforation) than in those with uncomplicated disease.
The second most common cause of PUD is NSAIDs, including low-dose aspirin. While H. pylori is most commonly associated with duodenal ulceration, NSAIDs are more commonly associated with gastric ulceration.
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A 35-year-old female presents to the ED with mild epigastric pain and dyspepsia. She has no other symptoms and denies weight loss. Her physical examination is unremarkable and she doesn’t have anaemia. You make the presumptive diagnosis of uncomplicated PUD.
Which ONE of the following statements is the MOST appropriate?
Answer: B: As the majority of PUD is caused by H. pylori, it is tempting to eradicate all patients with suspected PUD. However, testing for H. pylori is easily done and the absence of H. pylori may have prognostic implications. H. pylori-negative ulcers appear to have a significantly worse outcome, especially if treated empirically for infection.
Various non-invasive techniques are available. The urea breath test is one such test that is highly sensitive and specific and is also useful in assessing eradication. H. pylori tests cannot demonstrate the presence of PUD but a negative test in patients not taking NSAIDs makes the likelihood of PUD low. Testing does not need to be done in the ED but treatment can appropriately be started in the ED with a PPI. The patient can then be referred to their primary care provider for further testing and, if positive, eradication therapy commenced. PPI is most effective when taken with or shortly before meals, as the acidic compartments within the stimulated parietal cell are essential for activation. PPI works poorly in fasting patients as well as when given simultaneously with other antisecretory agents (H2 receptor blockers).
Not all patients with dyspepsia require endoscopy but those with alarm features do, as they raise the index of suspicion for gastric or oesophageal cancer. ‘Alarm features’ suggesting the need for endoscope referral include:
Regarding the aetiology of upper gastrointestinal tract (GIT) bleeding in adults, which ONE of the following is TRUE?
Answer: A: Upper gastrointestinal bleeding (UGIB) is regarded as bleeding originating from a site proximal to the ligament of Treitz. The ligament of Treitz is a fold of peritoneum that suspends the fourth part of the duodenum.
Peptic ulcer disease (gastric, duodenal, oesophageal and stomal ulcers) is the most common cause of upper gastrointestinal bleeding, accounting for 35–50% of all cases. Erosive gastritis, oesophagitis and duodenitis are responsible for about 15%, whereas oesophageal and gastric varices account for about 10% of cases. Mallory-Weiss tears (longitudinal mucosal lacerations at the gastroesophageal junction or gastric cardia) account for a further 5–15%. It is classically associated with repeated retching or vomiting; however, repeated vomiting is only present in one-third of cases. The remaining cases include rare causes like angiodysplasia and aortoenteric fistulae.
Aortoenteric fistulae usually develop secondary to a pre-existing graft. The initial bleed is usually not significant and self-limited (‘herald bleed’) and the diagnosis is confirmed with an abdominal CT, not endoscopy. One should have a high index of suspicion in patients with previous abdominal vascular surgery, as a herald bleed precedes massive haemorrhage, which is difficult to control and often fatal.
Which ONE of the following is TRUE regarding the clinical manifestations of upper GIT bleeding?
Answer: D: Although most patients with upper GIT bleeding present with a chief complaint of haematemesis or blood in the stool, this is not always the case. Upper GIT bleeding can present subtly with hypotension, tachycardia, dizziness, angina, confusion or syncope without any melena or haematemesis and clinical suspicion for GIT bleeding must remain high in these patients.
The presence of haematemesis is highly suggestive of bleeding from the upper GIT tract. Although placement of a nasogastric tube in the ED to assess aspirate is no longer routinely recommended, it may still have diagnostic and therapeutic benefits. In patients presenting with haematemesis, it may help to assess the presence of ongoing bleeding as well as prepare the patient for endoscopy. In patients presenting without haematemesis, a positive aspirate provides strong evidence for an upper GIT source. However, a negative aspirate does not exclude an upper GIT source and may result from intermittent bleeding, pyloric spasm or oedema preventing reflux of duodenal blood.
Melena usually represent bleeding from an upper GIT source (70%) but can rarely be due to a lower GIT source (20–30%). The black, tarry stool is produced as result of bacterial degradation of haemoglobin in the gut. At least 150–200 mL of blood that has spent at least 8 hours in the intestines is necessary to produce melena. Melena of itself is not associated with poorer outcomes in upper GIT bleeds but haematochezia is associated with a three times higher risk of death. Haematochezia is the passage of bright red or maroon-coloured blood per rectum and suggests a source distal to the ligament of Treitz. Approximately 14% of bleeds presenting with hematochezia are caused by a brisk upper source with rapid transit. Haematochezia due to an upper tract source of bleeding has been associated with a higher transfusion requirement, need for surgery and mortality rate.
Investigations are commonly performed in patients with upper gastrointestinal bleeding. Regarding this, which ONE of the following is TRUE?
Answer: C: A routine CXR is of limited value in patients with an upper GIT bleed and not needed in the absence of specific clinical indications. Additionally, it has not been found to alter clinical outcomes or management decisions in the absence of pulmonary examination findings or known pulmonary disease. A CXR is indicated in the following cases:
Perforation associated with significant upper GIT bleed is rare. CXR is only 70–80% sensitive for picking up a perforated peptic ulcer. Therefore, a negative CXR for free air under the diaphragm does not exclude perforation and an abdominal CT should be performed if in doubt. The initial haemoglobin level often will not reflect the actual amount of blood loss, as 24–48 hours is required for intravascular volume to equilibrate. Normal haemoglobin levels therefore do not exclude a large bleed. A haemoglobin level of <100 g/L has been associated with increased rebleeding and mortality rates. An elevated urea level relative to creatinine is more indicative of an upper rather than lower GIT source, as there is a combination of increased protein load in the gut and intravascular volume depletion.
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