Pathology of the gut - PC Flashcards
What is Barrett’s oesophagus
distal oesophagus is lined by columnar cells due to metaplasia
lined by gastric muscle which can develop goblet cells via intestinal metaplasia
what type of epithelium lines the oesophagus
stratified squamous
what is metaplasia
replacement of one differentiated cell type with another in repose to chronic injury or irritation
what is the OJG or Z line
normal oesophogastric junction where squamous mucosa of oesophagus and columnar oesophagus of stomach meet
risk factors for BO
High BMI alcohol tobacco smoking drugs relaxing LOS eg nitroglycerins familial/genetic predisposition
pathogenesis of BO
Reflux of acidic contents from stomach into oesophagus (reflux oesophagitis)
squamous to columnar epithelium via metaplasia
adaptation to injury via gastric contents
columnar epithelium increases risk of adenocarcinoma (precancerous stage of dysplasia)
pathogenesis of Barrett’s associated carcinoma
squamous epithelium reflux oesophagitis gastric epithelium intestinal metaplasia low to high grade dysplasia Adenocarcinoma
complications of coeliac disease
malnutrition osteoporrosis infertility and miscarriage cancer lactose intolerance NS problems
other conditions associated with coeliac disease
T1 DM AI disorders Downs and Turner syndrome thyroid disease MS Dermatistis anaemia neurological disorders
how does small bowel mucosa appear in coeliac disease
inc no of eosinophils
pathological inc in lymphocytes
atrophy of intestinal villi with chronic inflammation in lamina propria
what is the predominant cell of acute and chronic inflammation
acute - neutrophils
chronic - lymphocytes
normal large bowel mucosa
crypts arranged a row like test tubes
goblet cells full of mucin
crypts separated by lamina propria with vessels and connective tissue
what does the bowel look like with uc
Inflammation confined to mucosa
crypt architecture destruction
indications for colectomy in uc
toxic megacolon
uncontrolled colonic bleeding
acute fulminant colitis after treatment
elective - abnormal growth/polyps/longstanding disease
risk factors for dysplasia
UC at early age
total uc - whole LB
repeat bouts of acute inflammation with short periods of remission
long duration of UC - total UC 8 years need annual surveillance colonoscopy to look for dysplasia
how does the bowel present in crohn’s
fissuring ulcer
transmural inflammation (full thickness of bowel wall)
no crypt distortion
complications of Crohn’s disease
obstruction ulcer fistulas anal fissure malnutrition cancer can also get anaemia, osteoporosis, arthritis, GB/Liver disease
what is diverticular disease
out pouching as a result of herniation of mucosa and submucosa through bowel wall weakness
common in low fibre diet
95% sigmoid colon
complicated by diverticulitis and perforation (faecal impaction and inflammation)- peritonitis
how does diverticular disease present
intestinal obstruction
mimic cancer
colo-vesical fístula, presents with pneumaturia
