C. diff, malabsorption disorders

Question 1

What is clostridium difficile?

Answer 1

C. diff is a Gram-positive, anaerobic, spore forming bacterium. It is present in approximately 3-5% of the adult population, remaining dormant in the presence of other normal gut flora. However, this natural balance can be disrupted by the use of antibiotics, resulting in opportunistic infection, causing C. diff (pseudomembranous) colitis.

Question 2

Which antibiotics are strongly associated with C. diff infection?

How long does it take for symptoms to manifest after antibiotic therapy begins?

Answer 2

C antibiotics

• Co-amoxiclav
• Cephalosporins
• Ciprofloxacin
• Clindamycin

Symptoms typically manifest 5-10 days after antibiotic therapy

Question 3

Clinical features of C. diff colitis

Answer 3

• Profuse watery diarrhoea
• Colicky abdominal pain
• Fever and rigors in severe cases

Question 4

Investigations for C. diff colitis

Answer 4

1. Arrange blood tests
   
   • FBC (↑WCC), ↑CRP, ↓albumin, U&Es (may be deranged secondary to dehydration)
2. Arrange stool testing
   
   • Stool samples should be sent for MC&S including C. diff cytotoxin analysis
3. Obtain imaging
   
   • AXR may show colonic dilation
4. Consider colonoscopy/flexible sigmoidoscopy
   
   • Not routinely performed but may be useful if there is diagnostic uncertainty

Question 5

Stepwise management of C. diff colitis

Answer 5

1. Infection control
   
   • Patients should be isolated to a side room with barrier nursing precautions
   • Alcohol hand gels should be avoided
2. Medication review
   
   • Stop all causitive agents, particularly antibiotics and PPI
3. Antibiotic therapy
   
   • Offer a 10-14 day course of 400mg oral metronidaxole in non-severe cases
   • Severe disease: IV metronidazole + ORAL vancomycin
4. Consider surgery
   
   • Surgery may be indicated in fulminant disease

Question 6

Define coeliac disease

Answer 6

An autoimmune disorder triggered by gluten consumption, resulting in small bowel inflammation and subsequent malabsorption.

Question 7

Epidemiology of coeliac disease

Answer 7

• Affects 1% of the population
• Bimodal age distribution - first peaking in infancy and also in the fouth to fifth decade of life, though it can present at any age
• Twice as common in women

Question 8

Clinical presentations of coeliac disease

Answer 8

• GI
  
  • malabsorption (steatorrhoea, abdominal pain, flatus)
  • Unexplained weight loss
• Metabolic
  
  • Faltering growth/failure to thrive in infants
  • Iron deficiency (microcytic anaemia)
  • B12 and folate deficiency (anaemia, polyneuropathy, epilepsy)
  • Hypocalcaemia (tetany, osteomalacia, osteoporosis)
• Dermatology
  
  • Dermatitis herpeiformis
  • Severe apthous oral ulcers

Question 9

What is dermatitis herpetiformis?

In what percentage of patients with coeliac disease does this occur?

Pathophysiology of these lesions?

Answer 9

A pruritic, vesicular rash, mainly affecting the extensor surfaces.

Up to 20% of patients with coeliac disease.

Deposition of IgA complexes in the dermis.

Question 10

Conditions associated with coeliac disease

Answer 10

• Autoimmune
  
  • type 1 DM, thyroid disease, PBC
• Cancer
  
  • lymphoma, breast, small bowel

Question 11

Investigations for coeliac disease

Answer 11

• Serological testing
  
  • total IgA and IgA anti-tTG are usually raised and are first line options
  • IgA anti-endomysial and IgG anti-gliding may be used as alternatives
• Duodenal biopsy
  
  • this gold standard investigation allows for a histopathological diagnosis
• Other tests
  
  • routine FBC may reveal microcytic/macrocyctic anaemia (secondary to iron, B12 or folate deficiency)
  • electrolyte imbalance - ↓Ca, ↓Mg, ↓albumin
  • HLA genetic testing may be considered if the diagnosis is still unclear

Question 12

What dietary advice should be given to patient prior to coeliac testing to ensure an accurate result?

Answer 12

Continue a gluten rich diet, with as least one gluten-containing meal per day for at least 6 weeks prior to testing.

Question 13

Classical histological findings of duodena biopsy for coeliac disease

Answer 13

• Sub-total villous atrophy (loss of finger like projections)
• Crypt hyperplasia
• Inflammatory infiltrate of the lamina propria, primarily comprising lymphocytes

Question 14

Coeliac disease management

Answer 14

• Strict lifelong gluten free diet
• Offer vitamin and mineral supplements - vitamin B, D and calcium

Question 15

What is small intestine bacterial overgrowth?

How does it present?

Investigation?

Treatment?

Answer 15

Primarily characterised by an increase in the number of bacteria in the small bowel.

Normally presents with malabsorption symptoms (diarrhoea and steatorrhoea).

Diagnosis confirmed by a hydrogen breath test.

Underlying cause treated if possible. Otherwise a cyclical antibiotic regime.

Question 16

Causes of SIBO

Answer 16

• Reduced gastric acidity
  
  • Long standing PPI therapy
  • Post-gastrictomy
• Reduced gut motility
  
  • Scleroderma
  • Diabetic gastroparesis
• Sructural abnormalities
  
  • Post-small bowel resections
  • Small bowel diverticulosis
  • Small bowel obstruction

Question 17

What is short bowel syndrome?

Answer 17

Short bowel syndrome refers to extensive bowel failure, most commonly due to massive surgical resections, ischaemic injury or congenital abnormalities.

Question 18

Symptoms of short bowel syndrome

Answer 18

Diarrhoea and malabsorption are major symptoms

Based on site of resection:

• Proximal bowel
  
  • iron deficiency
  • micronutrient deficiency
• Distal ileum
  
  • B12 deficiency
  • Interrupts bile salt absorption
  • Increased colonic oxalate reuptake
• Colon
  
  • water and sodium loss
  • loss of fatty acid absorption

Question 19

Definition of irritable bowel syndrome

Answer 19

A functional disorder in which abdominal pain or discomfort is associated with defecation and/or a change in bowel habit in the absence of an organic cause.

Question 20

Epidemiology of irritable bowel syndrome

Answer 20

• More common in women and the younger population (20-30 years)
• Worldwide prevelence of 10-20%

Question 21

Clinical features of irritable bowel syndrome

Answer 21

Patients usually present with a 6 month history of:

• Abdominal pain or discomfort
• Bloating
• Change in bowel habit

Question 22

Diagnosis of IBS

Answer 22

• Elicit red flag sings and symptoms requiring urgent secondary care referral
  
  • Unintentional weight loss
  • Rectal mass/bleeding
  • Family history of bowel/ovarian cancer
  • Ageed over 60 with >6 weeks of altered bowel habit
• Use Rome criteria to aid the diagnosis of IBS:
  
  • Abdominal discomfort/pain for ≥12 weeks associated with 2 or 3 of the following:
    
    • ​​​​Relieved by defecation
    • Onset associated with change of bowel frequency
    • Onset associated with change of bowel form
  • Other supportive symptoms (at least 2):
    
    • Altered stool passage
    • Other abdominal symptoms (eg distension)
    • Prandial association
    • Mucus discharge per rectum

Question 23

Management of irritable bowel syndrome

Answer 23

• Lifestyle changes - encourage physical therapy and leisure time
• Dietry change
  
  • encourage regular meal and adequate hydration, avoid high-fibre/starch
  • low FODMAP diet
• Consider pharmacological therapy - based on predominant symptoms
  
  • anti-spasmodic, laxatives or antimotility
  • amitriptyline may be used as a second line agent
• Consider psychological therapy
  
  • CBT, psychotherapy,