Abdominal: Irritable Bowel Syndrome (IBS)

Question 1

What are some possible causes of IBS?

Answer 1

• Visceral hypersensitivity.
• Abnormal gastrointestinal immune function.
• Changes in colonic microbiota.
• Abnormal autonomic activity.
• Abnormal central pain processing of afferent gut signals (altered ‘brain-gut interactions’).
• Abnormal gastrointestinal motility.
• Hormones; Many women find that signs and symptoms are worse during or
  around their menstrual periods.

Question 2

What are risk factors of IBS?

Answer 2

• Genetics
• Enteric infection (for example, following gastroenteritis).
• Gastrointestinal inflammation (for example, secondary to inflammatory bowel
  disease) .
• Dietary factors (such as alcohol, caffeine, spicy and fatty foods)
• Drugs, such as antibiotics.
• Being female.
• Psychosocial such as associated stress, anxiety and/or depression.

Question 3

what is are the 4 categories of IBS?

Answer 3

• Diarrhoea predominant (IBS-D), which is the commonest sub-type.
• Constipation predominant (IBS-C).
• Mixed, fluctuating between diarrhoea and constipation (IBS-M).
• Unclassified (IBS-U).

Question 4

what are clinical features of IBS?

Answer 4

• Abdominal pain
• Bloating
• Change in bowel habit
• cramping
• excess gas
• diarrhoea
• constipation
• mucus in stool
• lethargy
• nausea
• backpain
• headache

Question 5

which conditions present in a similar way to IBS?

Answer 5

• Malignancy (such as colorectal cancer, small bowel cancer, and lymphoma).
• Other causes of constipation such as; Functional or drug-induced constipation and hypothyroidism.
• Other causes of diarrhoea such as; IBD, coeliac disease, gastroenteritis, antibiotic-associated diarrhoea, hyperthyroidism, laxative misuse.
• Other causes of abdominal pain or discomfort such as; Diverticular disease, Chronic pancreatitis, Gallstones, Peptic ulcer disease, Gastro-oesophageal reflux disease.

Question 6

when would you make a diagnosis of IBS?

Answer 6

if the patient has abdo pain related to:

• Related to defecation.
• Associated with altered stool frequency (increased or decreased).
• Associated with altered stool form or appearance (hard, lumpy, loose, or watery); and there are at least two of the following; Altered stool passage (straining, urgency, or incomplete evacuation), Abdominal bloating (more common in women than men), distension, or hardness.
• Symptoms worsened by eating.
• Passage of rectal mucus.
• Alternative conditions with similar symptoms have been excluded.

Question 7

what investiagtions would you consider for an IBS diagnosis?

Answer 7

• Full blood count (FBC).
• Inflammatory markers such as erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP).
• Coeliac serology.

Note: IBS is a diagnosis of exclusion, there is no specific investigation to confirm a diagnosis.

Question 8

what is the initial management of IBS?

Answer 8

• provide advice
• manage associated stress/anxiety/depression
• dietary advise
• over the counter probiotic supplements
• fibre supplements
• drinking fluids
• encourage regular physical activity

Question 9

with reference to IBS, If symptoms persist despite initial dietary and lifestyle advice, what does further medication management options include?

Answer 9

• laxative for constipation.
• Linaclotide for refractory constipation symptoms.
• Loperamide for diarrhoea symptoms.
• An antispasmodic drug for abdominal pain or spasm e.g. buscopan.
• A low-dose tricyclic antidepressant (TCA) for refractory abdominal pain.

Question 10

what would you prescribe if a TCA is ineffective, contraindicated, or not tolerated?

Answer 10

A selective serotonin reuptake inhibitor (SSRI)

Question 11

what are the complications of IBS?

Answer 11

• Poor quality of life.

- Mood disorders e.g. depression or anxiety, which can also make the symptoms of IBS worse.