Malabsorption

Question 1

What is the primary purpose of the GI tract?

Answer 1

Digestion, which is the process of breaking down food into substrates that can be absorbed.

Question 2

Name three digestive enzymes involved in the digestion process.

Answer 2

• Salivary amylase
• Gastric lipase
• Pepsins

Question 3

What is malabsorption?

Answer 3

The inadequate absorption of fluid, macro or micronutrients to maintain health.

Question 4

What is maldigestion?

Answer 4

Problems in any digestive phase of food or nutrient processing, commonly relating to digestive enzyme insufficiency or inefficiency.

Question 5

What can cause reduced absorptive capacity in malabsorption?

Answer 5

• Villous atrophy (e.g. Coeliac disease)
• Mucosal damage (e.g. Crohn’s disease)
• Enzyme deficiencies

Question 6

How can malabsorption present in patients?

Answer 6

• Diarrhoea
• Steatorrhoea
• Bloating
• Abdominal pain

Question 7

What are two common symptoms of malnutrition due to malabsorption?

Answer 7

• Weight loss
• Failure to thrive

Question 8

What is a common diagnostic test for malabsorption?

Answer 8

72-hour faecal fat test.

Question 9

True or False: Malabsorption is relatively rare.

Answer 9

True.

Question 10

What dietary modifications can help restore nutritional status in malabsorption?

Answer 10

High protein, low fat, Medium Chain Triglyceride (MCT) diet.

Question 11

What is Coeliac disease?

Answer 11

Chronic autoimmune-mediated gluten-sensitive enteropathy caused by exposure to cereal prolamins in genetically susceptible individuals.

Question 12

What is the prevalence of Coeliac disease in Caucasians?

Answer 12

~1%.

Question 13

What are some gastrointestinal symptoms of Coeliac disease?

Answer 13

• Chronic or intermittent diarrhoea
• Bloating
• Weight loss

Question 14

What serological test is most widely used for diagnosing Coeliac disease?

Answer 14

TTG IgA.

Question 15

What is the recommended management for Coeliac disease?

Answer 15

A lifelong gluten-free diet.

Question 16

Fill in the blank: Malabsorption can be caused by _______.

Answer 16

[maldigestion or loss of absorptive surface area]

Question 17

What are some causes of mucosal damage leading to malabsorption?

Answer 17

• Crohn’s disease
• Radiation enteropathy
• NSAIDs

Question 18

What is the role of the enteric nervous system in digestion?

Answer 18

It controls the motility and secretions of the gastrointestinal tract.

Question 19

What is the significance of the ‘ileal brake’?

Answer 19

It regulates intestinal transit and absorption.

Question 20

True or False: Secondary lactose intolerance is very rare.

Answer 20

False.

Question 21

What is the modified Marsh criteria used for?

Answer 21

Histological diagnosis of Coeliac disease.

Question 22

What is required for the diagnosis of Coeliac disease?

Answer 22

Ongoing gluten exposure.

Question 23

List two risk factors for malabsorption.

Answer 23

• Surgery
• Autoimmunity

Question 24

What is the purpose of a hydrogen breath test in malabsorption diagnosis?

Answer 24

To assess for carbohydrate malabsorption, such as lactose intolerance.

Question 25

What nutrient deficiencies are common in malabsorption?

Answer 25

* Iron deficiency * Vitamin B12 deficiency

Question 26

What is non-responsive Coeliac Disease?

Answer 26

Ongoing symptoms 12 months after GFD implemented ## Footnote GFD stands for Gluten-Free Diet.

Question 27

What should be considered if there are no high-risk features in a non-responsive Coeliac Disease patient?

Answer 27

Monitoring as most people take 2+ years for mucosa to fully heal

Question 28

What are some associated conditions or mimics of refractory Coeliac Disease?

Answer 28

SIBO, microscopic colitis, lactose intolerance, IBD, Thyroid disease, DM, PEI, BAM, infection, IBS

Question 29

What should be done if atrophy is found in a patient suspected of having refractory Coeliac Disease?

Answer 29

Consider coeliac histological mimics, inadvertent gluten contamination, slow healing, supersensitivity, and refractory coeliac sprue (RCD1 and 2)

Question 30

What is the survival rate for patients with RCD1?

Answer 30

>90% 5-year survival

Question 31

What characterizes RCD2?

Answer 31

Aberrant and/or clonal IEL cell lines

Question 32

What is the treatment for RCD2?

Answer 32

Steroids, escalating immunosuppression ## Footnote 5-year survival <50%

Question 33

What are some potential malignancies associated with refractory Coeliac Disease?

Answer 33

Enteropathy-associated T cell lymphoma, Non-Hodgkin’s lymphoma, Small bowel adenocarcinoma

Question 34

What is Tropical Sprue?

Answer 34

Malabsorption syndrome likely caused by aerobic enterobacteria, presents with weight loss, B12 and Folate deficiency

Question 35

What is the diagnosis for Tropical Sprue?

Answer 35

D2 Bx showing villous atrophy and lymphocytic infiltrate, travel history, negative screen for coeliac and other causes

Question 36

What is Whipple’s disease caused by?

Answer 36

Tropheryma whipplei

Question 37

What are the common symptoms of Whipple’s disease?

Answer 37

Malabsorption syndrome, GI bleeding, migratory arthritis, sacroiliitis, confusion, ataxia, extra-pyramidal signs

Question 38

How is Whipple’s disease diagnosed?

Answer 38

OGD and D2Bx showing PAS-stained foamy macrophages and PCR for T. Whipplei

Question 39

What is the treatment for Giardiasis?

Answer 39

Metronidazole

Question 40

What is the primary diagnosis tool for pancreatic exocrine insufficiency?

Answer 40

FE1 <200 ug/g is positive

Question 41

What are some associated conditions with pancreatic exocrine insufficiency?

Answer 41

* Chronic pancreatitis * Pancreatic cancer * Cystic fibrosis * Pancreatic resection * Acute pancreatitis * Untreated coeliac * Refractory coeliac * HIV on ARVs * Type 1 Diabetes * Type 2 Diabetes * UGI surgery * Alcohol * Smoking

Question 42

What is a common treatment approach for pancreatic exocrine insufficiency?

Answer 42

Pancreatic enzyme replacement therapy (PERT)

Question 43

What is the initial dose for pancreatic enzyme replacement therapy?

Answer 43

50,000 units with meals, 25,000 units with snacks

Question 44

What dietary modifications are recommended for managing pancreatic exocrine insufficiency?

Answer 44

Low fat, high protein, MCT diet

Question 45

What is Small Intestinal Bacterial Overgrowth (SIBO)?

Answer 45

Loss of normal bacterial balance in the small bowel

Question 46

What are common symptoms of SIBO?

Answer 46

Maldigestion, bloating, diarrhoea, B12 deficiency

Question 47

What is the gold standard for diagnosing SIBO?

Answer 47

Quantitative culture of jejunal fluid (> 10^3/mL is abnormal)

Question 48

What is the treatment for SIBO?

Answer 48

Rifaximin 550mg TDS for 10-14 days

Question 49

What is the significance of a low FE1 in diagnosing pancreatic exocrine insufficiency?

Answer 49

Low FE1 is insufficient on its own to make a diagnosis; the whole clinical picture needs to be considered

Question 50

What are the common causes of malabsorption?

Answer 50

* Coeliac disease * Tropical sprue * Whipple’s disease * SIBO * Pancreatic exocrine insufficiency

Question 51

What should be done in cases of diagnostic doubt for pancreatic exocrine insufficiency?

Answer 51

Repeat FE1 testing and consider PPI washout period

Question 52

What is the typical presentation of a patient with malabsorption?

Answer 52

Diarrhoea, abdominal pain, bloating, weight loss

Question 53

What are some key take-home messages regarding malabsorption?

Answer 53

* Check coeliac serology and faecal elastase * Common causes should be excluded * Specific and effective treatments available