6.8 - Gastrointestinal infections

Question 1

What are some differential diagnoses (microorganisms) for infectious diarrhoea? (6)

Answer 1

• Clostridium difficile
• Klebsiella oxytoca
• Clostridium perfringens
• Salmonella spp
• Shigella
• E. coli

Question 2

What are some differential diagnoses for non-infectious diarrhoea? (7)

Answer 2

• antibiotics side effect
• post-infectious irritable bowel syndrome
• inflammatory bowel disease
• microscopic colitis
• ischaemic colitis
• coeliac disease
• haemorrhoids

Question 3

What investigations can be ordered for diarrhoea? (4)

Answer 3

• stool sample for C. difficile toxin
• stool culture, calprotectin & FIT
• imaging (AXR, CT)
• endoscopy (flexible sigmoidoscopy, colonoscopy)

Question 4

How can you manage infectious diarrhoea?

Answer 4

• infection control - patient moved to side room
• discontinue inciting antibiotic agents e.g. stop co-amoxiclav
• management of fluids, nutrition and diarrhoea

Question 5

How can you differentiate between non-severe and severe C. diff infections?

Answer 5

• non-severe infection: WCC<15, creat<150
• severe infection: WCC>15, creat>150

Question 6

What is fulminant colitis?

Answer 6

Hypotension or shock, ileus, toxic megacolon

(Ileus = bowel blockage)

Question 7

How do you treat non-severe C. diff induced diarrhoea?

Answer 7

• antibiotic therapy with oral vancomycin or fidaxomicin or metronidazole
• role of faecal microbiota transplantation (FMT)

Question 8

How do you treat severe C. diff induced diarrhoea / fulminant colitis?

Answer 8

• antibiotic therapy, supportive care and close monitoring
• early surgical consultation

Question 9

What is the 1st line treatment for fulminant colitis with toxic megacolon?

Rare but serious complication of colonic inflammation –> dilation

Answer 9

Medical therapy with antibiotics and supportive management

Question 10

Fulminant colitis with toxic megacolon - what are the indications for surgery? (5)

Answer 10

• colonic perforation
• necrosis or full-thickness ischaemia
• intra-abdominal hypertension or abdominal compartment syndrome
• clinical signs of peritonitis or worsening abdominal examination despite adequate medical therapy
• end-organ failure

Question 11

What is pseudomembranous colitis?

Answer 11

• most often associated with C. difficile infection
• manifestation of severe colonic disease
• characteristic yellow-white plaques that form pseudomembranes on the mucosa
• confirmed on endoscopy +/- biopsy

Question 12

What are the management options for ulcerative colitis? (5)

Answer 12

• steroids
• 5 ASA
• immunosuppressants - azathioprine, methotrexate
• biologic therapy
• others - diet, FMT, Abx, probiotics, novel agents

Question 13

What are some different methods of classifying ulcerative colitis severity?

Answer 13

Different scopes including clinical disease activity index, Montreal classification and Trulov & Witt scores

Question 14

What is the difference between mild, moderate and severe ulcerative colitis?

Answer 14

• mild: 4x bowel movements/day, no systemic toxicity, normal ESR/CRP, mild symptoms
• moderate: >4x bowel movements/day, mild anaemia, mild symptoms, minimal systemic toxicity, nutrition maintained and no weight loss
• severe: >6 bowel movements/day, severe symptoms, systemic toxicity, significant anaemia, increased ESR/CRP and weight loss