Gastro Flashcards
Causes of bloody diarrhoea
VASCULAR - ischaemic colitis
INFECTIVE - campylobacter, shigella, salmonella, E. coli, amoeba, pseudomembranous colitis
INFLAMMATORY - UC, Crohn’s
NEOPLASTIC - CRC, polyps
C diff
- gram stain
- toxins
- spore survival time
- Gram -ve spore-forming anaerobe
- releases enterotoxins A and B
- Spores can survive for >40 days
risk factors for c diff infection
- Abx especially clindamycin, cefs, augmentin and quinolones
- increased age
- increased length of hospital stay
- PPIs
Pseudomembranous Colitis
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
treatment of c. difficile pseudomembranous colitis
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
Causes of constipation
OPENED IT
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
Definition of IBS
Disorders of enhanced visceral perception -> bowel symptoms for which no organic cause can be found
ROME criteria for IBS
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
Inflammatory causes of dysphagia
- Tonsillitis, pharyngitis
- Oesophagitis: GORD, candida
- Oral candidiasis
- Aphthous ulcers (idiopathic)
Mechanical causes of dysphagia
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
Motility disorders causing dysphagia
LOCAL achalasia diffuse oesophageal spasm nutcracker oesophagus bulbar/pseudobulbar palsy (CVA, MNA) SYSTEMIC systemic sclerosis/ CREST myasthenia gravis
pathophysiology of achalasia
degeneration of myenteric plexus (Auerbach’s) -> decreased peristalsis -> lower oesophageal sphincter fails to relax
Presentation of achalasia
Dysphagia: liquids and solids at same time
Regurgitation
Substernal cramps
Weight loss
Treatment of achalasia
- calcium channel blockers, nitrates
- endoscopic balloon dilatation, botox injection
- Heller’s cardiomyotomy
Pharyngeal pouch - Zenker’s Diverticulum definition
Outpouching of oesophagus between upper border of cricopharyngeus muscle and lower border of inferior constrictor of pharynx
Weak area called Killian’s dehiscence