Gastroenteritis

Question 1

What is gastroenteritis?

Answer 1

Gastroenteritis is the term used to describe inflammation of the gastrointestinal tract, usually considered infective in origin (although can also be non-infective).

They are most often transient, presenting with combination of symptoms such as diarrhoea, vomiting and abdominal pain, although not all have to be present in order to make the diagnosis.

Question 2

What is the most common cause of gastroenteritis?

Answer 2

The most common cause is viral, contributing to 30-40% of gastroenteritis in developed countries.

Question 3

How can the time of onset of gastroenteritis indicate the causative organism?

Answer 3

Subtle differences in the length of time between ingestion of food and development of symptoms can often reveal the causative agent; as a general rule:

• Bacterial toxins = hours
• Viruses = days
• Bacteria = weeks
• Parasites = months

Question 4

Define the following terms:

• Diarrhoea
• Acute diarrhoea
• Chronic diarrhoea
• Dysentery
• Traveller’s diarrhoea

Answer 4

Diarrhoea: 3 or more loose stools or stools with increased liquid per day (as defined by the WHO).

Acute diarrhoea: lasting less than 14 days.

Chronic diarrhoea: lasting more than 14 days.

Dysentery: gastroenteritis characterised by loose stools with blood and mucus.

Travellers’ diarrhoea: more than 3 loose stools commencing within 24 hours of foreign travel, with or without cramps, nausea, fever, or vomiting.

Question 5

What are the risk factors for gastroenteritis?

Answer 5

• Poor food preparation, especially in handling and cooking
• Immunocompromised
• Poor personal hygiene

Question 6

What are the clinical features of gastroenteritis?

Answer 6

Patients will typically present with a cramp-like abdominal pain and diarrhoea (with or without blood or mucus). There may be associated vomiting, night sweats and weight loss reported.

On examination, the patient will often be dehydrated (of varying severity) with potential pyrexia.

Specific features from the history to note for any suspected cases of infective gastroenteritis include:

• Bowel movements (blood stained, mucus, profusely watery)
• Affected family or friends
• Recent travel abroad
• Recent use of antibiotics within the previous four weeks
  
  • Can suggest potential C. difficile infection

Question 7

What investigations should be ordered for gastroenteritis?

Answer 7

Investigations are not necessary for most cases, as the condition is usually self-limiting.

However, a stool culture is often warranted, especially in cases with blood or mucus in the stool, if the patient is immunocompromised, or if severe or persistent.

Question 8

Briefly describe the management of gastroenteritis

Answer 8

The general points of management for any patient with gastroenteritis include:

• Rehydration, encouraging oral fluid intake where possible
  
  • If severe dehydration or unable to tolerate oral fluid, the patient may need admission for intravenous fluid rehydration
• Education to prevent future episodes
• Exclusion from work is usually 48 hours from the last episode of vomiting or diarrhoea

Question 9

When is gastroenteritis a notifiable disease?

Answer 9

In the UK, both food poisoning and infectious bloody diarrhoea are notifiable diseases and it is the duty of the diagnosing doctor to notify the appropriate body.

Certain organisms are also notifiable (Campylobacter and Salmonella), however this is the duty of the laboratory identifying the organism to notify the Public Health body about this.