Infectious colitis

Question 1

Define

Answer 1

inflammation of the colon due to bacteria, parasites or viruses

Question 2

Causes

Answer 2

• Viruses and bacteria – most are food-borne illnesses Commonly bacterial: Shigella, E.coli, salmonella, campylobacter
•  Parasites – enters the body when infected water is swallowed, e.g. entamoeba histolytica (most common worldwide), giardia

Question 3

Risk factors

Answer 3

• Recent travel to the developing world
• Exposure to contaminated water source or areas of poor sanitation
• Exposure to others suffering from infectious colitis Immunocompromised are at an ↑risk
• Recent antibiotic treatment (also PPI treatment) Advanced age

Question 4

Symptoms and signs

Answer 4

May include:

• Mild-sever abdomen pain and tenderness
• Diarrhoea ±blood, ±pus
• Faecal incontinence
• Flatulence/bloating/distension (as ↑gas production)
• Fatigue, loss of appetite, unexplained weight loss
• Headaches, body aches

Bacterial → bloody diarrhoea, significant dehydration, abdomen cramps
Parasites → significant diarrhoea
Pseudomembranous colitis → non-bloody diarrhoea,

Question 5

Investigations

Answer 5

Diagnosis is largely CLINICAL

Stool culture may be used to identify the causative organism