Malabsorption

Question 1

Malabsorption

Answer 1

occurs when an individual is unable to absorb macro/micronutrients from their diet

Question 2

4 causes of malabsorption:

Answer 2

• alterations to secretions
• alterations in structure/absorptive capacity
• alteration in motility
• reduction in blood flow

Question 3

Diagnostic features of malabsorption:

Answer 3

• change in bowel movements or contents
• abdominal distension
• flatulence
• loss of weigth/growth failure
• hypoproteinaemia (low serum albumin)
• iron deficiency anaemia or low serum ferritin

Question 4

Presenting features of fat malabsorption:

Answer 4

• steatorrhoea (pale, malodorous, greasy. unformed
  stools)
• often difficult to flush
• may leave greasy residue in the toilet

Question 5

Presenting features of carbohydrate malabsorption:

Answer 5

• typically water
• frothy diarrhoea
• presence of fermented sugars

Question 6

Dietary treatment for malabsorption:

Answer 6

• replace large fluid and electrolyte losses
• treat the primary disorder if appropriate
• provide symptom relief
• restore optimal nutritional status with
  supplementation for micronutrients
• increasing the amount taken orally may not lead to
  increased absorption
• vitamin B12 is absorbed in terminal ileum, if this is
  removed no B12 will be absorbed therefore need
  injections

Question 7

gastric resection- gastric function disturbances

Answer 7

Question 8

Alteration in gastric motility

Answer 8

• markedly accelerated gastric emptying can induce
  dumping syndrome with malabsorption of fluids and
  nutrients leading to diarrhoea
• dumping syndrom: following gastric resection:
• early dumping: sweating, dizziness, faintness, rapid
  weak pulse, hypotension; causes rapid and early
  delivery of hyperosmolar load into the jejunum
• late dumping: symptoms of weakness, cold, faintness, sweating 2 hours after a meal; cause: overproudctoion of insulin in response to rapid absoprtion of glucose

Question 9

Early dumping syndrom symptoms often reced after how long
how can symptoms be helped

Answer 9

• 2-3 months
• small meals, limiting consumption of rapidly
  absorbed carbs and not having drinks with meals

Question 10

Alterations to secretions: Enzyme deficiencies (small intestine):

Answer 10

• disaxxharidase deficiency: primarly alactasia or secondary lactase deficiency

Question 11

Alterations to secretions: Intraluminal deficiencies (small intestine):

Answer 11

• high pH in duodenum: achlorhydria
• low pH in duodenum: Zollinger-Ellinson syndrome

Question 12

varying degrees of lactase deficiency can lead to lactose remaining in the small intestine leading to

Answer 12

osmotic diarrhoea
colonic bacteria further ferment the lactose resulting in symptoms such as abdo distension, flatulence and explosive watery diarrhoea

Question 13

Three main types of lactase deficiency:

Answer 13

• congenital alactasia
• primary lactase deficiency
• secondary lactase deficiency

Question 14

Congenital alactasia

Answer 14

• rare autosomal recessive disorder
• complete absence of lactase requiring total and
  permanent lactose exclusion

Question 15

Primary lactase deficiency

Answer 15

• gradual reduction in lactase production causes
  symptoms of lactose maldigestion in older children
  and adults
• undigested lactose and products of its bacterial
  fermentation can cause GI symptoms

Question 16

Secondary lactase deficiency

Answer 16

• common ususally temporary consequence of damage
  to intestinal brush border
• characterised by diarrhoea that persists after the
  primary disorder has been treated

Question 17

Alterations in structure

Answer 17

Question 18

Coeliac disease:

Answer 18

• inflammatory condition of the small intestine mucosa
  induced by ingestion of gluten
• leads to malabsorption, weight less, malnutrition
• not all patients have weight loss, but may have poor
  calcium levels causing anaemia and osteoporosisi
• improves when gluten is excluded from the diet

Question 19

Inflammatory Bowel Disease

Answer 19

• signficant impact on quality of life
• clinical features: abdo pain, diarrhoea, blood, mucous,
  urgency
• dependent on the site is what is unabsorbed
• vitamin and mineral deficiencies
• routine multivitamin supplementation reccomended
• iron deficiency primary causes of anaemia in IBD

Question 20

Intestinal Failure

Answer 20

reduction of gut functions below minimum necessary for the absorption of macronutrients, water and electrolytes, such as IV supplements for health and growth

effects of IF are best understood by considering where the nutrients are normally ansorbed

Question 21

Treating steatirrhiea

Answer 21

• starts when 90% exocrine function of pancreas is lost
• consider pancreatic enzyme replacement early on in
  patients loosing weight with pancreatic insufficiency
• do not treat with fat restriction alone

Question 22

Resection of the large intestine results in condierable absorptive loss for

Answer 22

fluids and electrolytes especially sodium
unable to absorb B12

Question 23

Toddle dairrhoea

Answer 23

• fructolysis occurs in the small intestine
• unabsorbed fructos enters the colon and acts as a
  substrate for bacteria, which produce short chain fatty
  acids
• GI disturbances such as bloating, abdo pain, loose
  stools and flatulence are symptomatic conequences
• in young children consumption of large amounts of
  apple and pear juice that contain large amounts of
  free fructose results in toddler diarrhoea which
  resolves when dietary fructose is limited