PBL 4 Flashcards
what is gastroenteritis
infection of the intestines
what is the presentation of gastroenteritis
• Causes diarrhoea and may also cause symptoms such as vomiting and abdominal pain.
o Usually the infection clears within a few days (can sometimes take longer).
what is the main risk of gastroenteritis
Main Risk: dehydration.
How do you treat gastroenteritis
Treatment: rehydration.
• May include rehydration drinks.
• Most children recover at home within a few days.
o 1/5 needs to see doctor.
o 1/10 ends up in hospital due to complications.
NOTE: many children have more than one episode in a year
How can the severity of gastroenteritis vary
Severity: can range from an upset stomach (from a day or two with mild diarrhoea) to severe diarrhoea and vomiting for several days or longer.
what are the causes of gastroenteritis
• Various bacteria, viruses and other microbes can cause it.
what is the most common cause of gastroenteritis
rotavirus
what other viruses can cause gastroenteritis
o Norovirus (may be as common as rotavirus), astrovirus and adenovirus.
when you tend to get the rotavirus
• Almost every child in the UK has a rotavirus infection before they are 5 years old
how do you prevent gastroenteritis
- vaccine
- good hygiene
- wash hands regular
- teach child to wash hands
- proper storage, preparation and cooking of food
describe the vaccine of rotavirus
• A vaccine against rotavirus was introduced in the UK in September 2013 (Brand name: Rotarix).
o Given drops by mouth at around 2 to 3 months old.
o Rotavirus vaccine has prevented more than 70% of cases.
Is lactose a disaccharide or a monosaccaride
• Disaccharide
where do you find lactose
mammalian milk and dairy products.
what is lactose broken down into
o Hydrolysed by lactase into the monosaccharides = glucose and galactose
what happens to the sugars glucose and galactose
These sugars can be transported across the brush border.
• Intracellular glucose goes into the portal capillary blood.
what is the most common cause of secondary lactose intolerance
• Most common cause of secondary lactose intolerance is gastroenteritis
describe the mechanism of action of how lactose can lead to diarrhoea
• The enzyme lactase is found on the brush border membrane of enterocytes lining the villi of the SI.
• When the lining of the small intestine is damaged, there will be a reduction/lack of lactase.
o Lactase cannot hydrolyse lactose.
If lactose is unhydrolysed, it cannot be absorbed and accumulates.
• Leads to an increase in osmolarity, which will cause water to be retained in the lumen of the SI.
Large Intestine
• Unabsorbed lactose will move into the LI/colon
o Metabolised by bacterial enzymes.
o Further increases the osmolarity in the lumen of the intestine and water retention.
How do you diagnose a lactose intolerance
• This bacterial fermentation also produces H2, CO2, CH4, lactic acid and acetic acid.
o Can be observed in the stool.
describe how an gastrointestinal infection leads to lactose intolerance
- so you have a gastrointestinal infection such as rotavirus
- this causes damage to the brush border enzymes of the small intestine which decreases lactase
- therefore there is an increase in the amount of lactose in the small intestine and thus an increase in the osmolarity and retention of water
- bacterial fermentation of lactose in the large intestine produces hydrogen, carbon dioxide and methane with the formation of lactic acid and acetic acid and reabsorbed water
- acids leads to the sore bottom
- gasses lead to wind and abdominal main
- water leads to frequent watery stools
what are the symptoms of gastroenteritis and explain what causes them
o Causes abdominal pain (CO2 and other gases).
o Acids causes sore bottom
o Water causes diarrhoea.
how do you treat secondary lactose intolerance caused by gastroenteritis
The condition gets better when the infection is finished.
• Cutting out dairy products from the diet for a few weeks/months will give the gut lining time to heal.
o Ability of the gut to produce lactase will build up again and the child will be able to eat dairy.
what are the risk factors that cause gastroenteritis causing lactose intolerance
- High sensitivity of the gut to infectious agents
- Low reserve because of the SI surface area.
- High reliance on milk-based products for nutrition.
what should you investigate if anklets diet does not improve on a lactose free diet
investigate for coeliac disease
what is faltering growth
Faltering growth (or failure to thrive) is used to describe suboptimal weight gain in infants/toddlers.
Mild faltering growth: fall across two centile lines.
Severe faltering growth: fall across the three centile lines
