Anatomical Path Flashcards
Non-specific symptoms of GIT disease
- Pain
- Nausea and vomiting
- Malabsorption – nutrient deficiency
- Loss of appetite/weight loss
- Diarrhea
- Constipation/obstruction
Signs of GIT disease
- Tenderness
- Abdominal distension
- Palpable mass
- Haemorrhage – due to ulceration, can present with anaemia + faecal occult blood
- Peritonitis due to perforation
- Systemic infection – sepsis
Vascular pathologies the GIT: arterial and venous
Arterial: occlusion results in ischaemia and infarction due to embolism/rupture
Venous: results in congestion, ischaemia with maybe infarction, due to mechanical obstruction
Consequences of infection/inflammation of the GIT
- pain, dysfunction, malabsorption and diarrhoea
- surface damage = ulceration, haemorrhage, perforation
Infection - can become septic
Consequences of trauma in the GIT
- Organ damage/rupture – necrosis, dysfunction, peritonitis
* Vascular damage – haemorrhage, haematoma, ischaemia, infarction
AI gastric diseases
- atrophic gastritis
- coeliac disease
Atrophic gastritis - antibodies are produced against the parietal cells of the gastric body. These cells secrete intrinsic factor which is essential for absorption of vitamin B12. Lack of this can result in pernicious (megaloblastic) anaemia.
Coeliac disease - where the gluten in wheat products triggers the body’s immune system to damage the absorptive enterocytes in the small bowel resulting in malabsorption, diarrhoea and anaemia. (not strictly autoimmune)
Signs and symptoms of neoplasm in GIT
- Mass – not often palpable till late
- Obstruction – dysphagia, constipation
- Haemorrhage from surface ulceration – anaemia, haematemesis/malena – shock
- Perforation – peritonitis, tumour seeding
4 layers in mucosa of the GIT
- Squamous epithelium
- basement membrane
- lamina propria
- muscular is mucosae
Layers in the muscularis propria
- inner circular muscular coat
- outer longitudinal muscle coat
- Auerbach nerve plexus
What is the GOJ and what cells are there?
Gastro-oesophageal junction
Where squamous mucosa of the oesophagus meets the columnar mucosa of the stomach
What is a sliding hernia?
Most common hernia, where part of the stomach is pulled up from above the diaphragm
Due to: congenitally short oesophagus or scarring following chronic injury
What is a rolling hernia (AKA paraoesophagheal hernia)
Part of the cardiac end of the stomach pushes through the diaphragm rolling up alongside the oesophagus
Causes of GORD
- LES disease
- hiatus hernia
- increased volume
- lifestyle
Clinical issues in GORD
- Mucosal damage
- infections
- complications - asthma, aspiration pneumonia, adenocarcinoma
Microscopic findings in GORD
- hyperplastic squamous cell epithelium
- swollen cells, spongiosis
- erosions
- ulcerations
- inflammatory cells
Eosinophilic oesophagi’s
- Cause
- Clinical issues
- Macroscopic features
- Allergen
- Abdo pain, vomiting, dysphagia, reflux
- mucosal rings, webs, stricture, vertical lines or furrows
Risk factors, clinical signs and management of candida oesophagitis
Risks: immunosuppression, chemo, steroids, surgery
Clinical: dysphagia
Mx anti fungals
What condition may an Owl’s inclusion be present?
Viral oesophagitis - CMV
What is Barrett’s oesophagitis?
Metaplasia - change from squamous cells of tubular oesophagus to intestinal type glandular mucosa/mucous secreting cells
Clinical: heartburn, cough, reflux, some no symptoms
2 main types of oesophageal cancer
- adenocarcinoma - malignant neoplasm with glandular differentiation
- squamous cell carcinoma - malignant neoplasm with squamous cell differentiation
Diagnosis of H.Pylori
Dyspepsia - urea breath test, serology, stool antigen assay
Endoscopy with biopsy
–Usually biopsy at time of endoscopy and urease breath test
What is AI gastritis and how does it present?
Immune response against parietal cells (acid/intrinsic factor)
Clinical - pernicious anaemia, iron deficiency anaemia
What stomach neoplasms can arise from these tissues:
- epithelial
- mesenchymal
- lymphoid
- neuroendocrine
- epithelial - dysplasia, carcinoma
- mesenchymal - GI stromal tumour
- lymphoid - MALT lymphoma
- neuroendocrine - carcinoid (NET)
4 Types of neuroendocrine tumour
Type I – secondary to AI gastritis – chronic gastrin hypersecretion
Type II – with Zollinger-Ellison (MEN I)
Type III – solitary, larger
Type IV – rare – parietal cell dysfunction
Most common cause of liver abscess
Pyogenic - bacterial in the biliary tract (enteric bacteria)
What is pancreatitis?
Inflammatory process caused by blockage of pancreatic bile duct by gallstones or chronic alcohol abuse. Pancreatic enzymes self digest organ and cause necrosis
What is cholangitis?
Infection of biliary system due to blockage of common bile duct by gallstone/tumour/stricture
What is cholecystitis?
Obstruction of cystic duct by gallstone
What does diverticulitis arise from?
Diverticulosis - sac like projections from colonic wall
Pathological findings in diverticulitis
- Local erosion
- inflammation
- necrosis of mucosa
- micro/macro perforation of diverticulum
Classification of peritonitis
- Primary - monomicrobial
- Secondary - polymicrobial usually, leakage of bacteria from bowel
- Tertiary - peritonitis in critically ill patient, persisting after mgmt
Empiric antibiotics for Liver abscesses, appendicitis, diverticulitis, acute peritonitis
Gentamicin
Amoxicillin
Metronidazole
What is duodenitis?
Peptic duodenitis is inflammation and damage to the proximal duodenum secondary to chronic overexposure to gastric acid
H. Pylori duodenal ulcer proposed pathogenesis
- Antral H. Pylori
- reduced astral D-cell somatostatin
- XS gastrin release
- trophic effect on parietal cells
- increased acid secretion
- duodenal damage - gastric metaplasia
- duodenal ulcer
Risk factors for GI events
- age
- ulcer history
- high dose NSAID’s
- major illness
- smoking/alcohol
Coeliac disease
Malabsorption due to chronic immune mediated reaction to gluten
Laboratory test for coeliac disease
Tissue transglutaminase - about 90% specific and sensitive
What is Meckel diverticulum?
Ileal out-touching due to the persistence of the congenital vitelline duct
Rule of 2’s for Meckel Diverticulum
o 2 inches in length (average)
o Located within 2 feet of ileocaecal valve
o Usually symptomatic before age 2
o See in 2% (1-4%) of the population
What can Giardia Lamblia be treated with?
Metronidazole
Crohn’s disease
¥ Relapsing, discontinuous, transmural granulomatous inflammation from oral cavity to anus
Histological findings in Crohn’s disease
- crypt abscesses
- granuloma
- ulceration
- hypertrophy
Presentation of small bowel adenocarcinoma and risk factors
Presentation: abd pain, obstruction, anaemia, GI bleeding, weight loss
Risks: Crohn’s, coeliac’s, polyposis syndromes
What is enterobius vermicularis commonly associated with?
Common infection in children, may cause appendix infection
Epithelial and non-epithelial colorectal neoplasms
Epithelial - adenoma - adenocarcinoma Non-epithelial - NE (carcinoid) - GI lymphoma - GI stromal tumour - mesenchymal tumour
What is a polyp?
Mass that protrudes into the lumen of the gut
Are adenomas cancer?
No - all adenomas are dysplastic, with NO invasion, they become cancer when they start invading