Gastro

Question 1

Causes of bloody diarrhoea

Answer 1

VASCULAR - ischaemic colitis
INFECTIVE - campylobacter, shigella, salmonella, E. coli, amoeba, pseudomembranous colitis
INFLAMMATORY - UC, Crohn’s
NEOPLASTIC - CRC, polyps

Question 2

C diff

• gram stain
• toxins
• spore survival time

Answer 2

• Gram -ve spore-forming anaerobe
• releases enterotoxins A and B
• Spores can survive for >40 days

Question 3

risk factors for c diff infection

Answer 3

• Abx especially clindamycin, cefs, augmentin and quinolones
• increased age
• increased length of hospital stay
• PPIs

Question 4

Pseudomembranous Colitis

Answer 4

Complication of c. difficile infection

• Severe systemic symptoms: fever, dehydration
• abdo pain, bloody diarrhoea, mucus PR
• Pseudomembranes (yellow plaques) on flexi sig
• Complications:
• -Paralytic ileus
• -Toxic dilation -> perforation
• -Multi-organ failure

Question 5

treatment of c. difficile pseudomembranous colitis

Answer 5

GENERAL

• stop causative abx
• Avoid antidiarrhoeals and opiates
• Enteric precautions

1ST LINE
- Metro 400mg TDS PO for 10-14 days
2ND LINE (if failed metro)
- Vanc 125mg QDS PO for 10-14 days
SEVERE
- Vanc 1st line +/- metro IV
- Urgent colectomy may be needed if:
-- toxic megacolon
-- increased LDH
-- deteriorating

RECURRENCE (15-30%)

• Reinfection or residual spores
• Repeat metro course for 10-14 days
• Vanc if further relapse

Question 6

Causes of constipation

OPENED IT

Answer 6

OBSTRUCTION
-Mechanical - adhesions, hernia, Ca, inflammatory strictures, pelvic mass
-Pseudo-obstruction: post-op ileus
PAIN
-anal fissure
-proctalgia fugax (idiopathic anal pain)
ENDOCRINE/ELECTROLYTES
- Endo: hypothyroid
- Elec: low calcium/potassium, uraemia
NEURO
- MS
- Myelopathy
- Cauda equine
ELDERLY
DIET/DEHYDRATION
IBS
TOXINS
- Opioids
- anti-mACh

Question 7

Definition of IBS

Answer 7

Disorders of enhanced visceral perception -> bowel symptoms for which no organic cause can be found

Question 8

ROME criteria for IBS

Answer 8

Abdo discomfort/pain for more than 12 weeks which has two of:

• Relieved by defecation
• Change in stool frequency
• Change in stool form

Plus two of:

• urgency
• incomplete evactuation
• abdo bloating / distension
• mucus PR
• worsening symptoms after food

EXCLUSION CRITERIA

• over 40
• bloody stool
• anorexia
• weight loss
• diarrhoea at night

Question 9

Inflammatory causes of dysphagia

Answer 9

• Tonsillitis, pharyngitis
• Oesophagitis: GORD, candida
• Oral candidiasis
• Aphthous ulcers (idiopathic)

Question 10

Mechanical causes of dysphagia

Answer 10

LUMINAL
food bolus
MURAL
web
oesophagitis
trauma
malignancy
pharyngeal pouch
EXTRA MURAL
Lung Ca
rolling hiatus hernia
mediastinal lymph nodes
retrosternal goitre
thoracic aortic aneurism

Question 11

Motility disorders causing dysphagia

Answer 11

LOCAL
achalasia
diffuse oesophageal spasm
nutcracker oesophagus
bulbar/pseudobulbar palsy (CVA, MNA)
SYSTEMIC
systemic sclerosis/ CREST
myasthenia gravis

Question 12

pathophysiology of achalasia

Answer 12

degeneration of myenteric plexus (Auerbach’s) -> decreased peristalsis -> lower oesophageal sphincter fails to relax

Question 13

Presentation of achalasia

Answer 13

Dysphagia: liquids and solids at same time
Regurgitation
Substernal cramps
Weight loss

Question 14

Treatment of achalasia

Answer 14

• calcium channel blockers, nitrates
• endoscopic balloon dilatation, botox injection
• Heller’s cardiomyotomy

Question 15

Pharyngeal pouch - Zenker’s Diverticulum definition

Answer 15

Outpouching of oesophagus between upper border of cricopharyngeus muscle and lower border of inferior constrictor of pharynx

Weak area called Killian’s dehiscence

Question 16

ALARM symptoms in dyspepsia

Answer 16

Anaemia
Loss of weight
Anorexia
Recent onset progressive symptoms
Melaena or haematemesis
Swallowing difficulty