Gastroenterology - Lower GIT Flashcards
What is the lower GI tract made up of
Small intestine: - Duodenum - Jejunum - Ileum Large intestine: - Colon - Ascending, transverse, descending segments Rectum and Anus
What are the main functions of the small intestine
Digestion
Absorption
What is absorbed in the duodenum of the small intestine
Iron + folate
What is absorbed in the jejunum of the small intestine
Other substances - miscellaneous i suppose
Name some of the things that are absorbed in the terminal ileum of the small intestine
- Gastric intrinsic factor
- Vitamin B12
- Bile salts
- Fats and fat soluble vitamins
What are some common disease of the small intestine
Coeliac disease
Crohn’s disease
What are the key features of small intestine diseases
- Malabsorption
- Diarrhoea or steatorrhoea
- Abdominal discomfort or pain
- Nutritional deficiencies - loss of weight, anaemia etc
What are the features of Steatorrhoea
- Bulky stools
- Float
- Greasy or fatty or frothy appearance
- Foul smell
- Difficult to flush away
What are the causes of Steatorrhoea
- Coeliac disease/Crohn’s
- Cystic fibrosis
- Pancreatitis
- Liver disease
What are some typical clinical features of coeliac disease
- Diarrhoea
- Weight loss
- Anaemia
What is the GIT sensitive to in coeliac disease
Has a toxic reaction/hypersensitivity to the alpha-gliadin component of gluten (wheat, oats, rye, barley etc)
What causes coeliac
T cell mediated autoimmune disease
What happens to the small intestine villous with gluten in coeliac patients
The jejunal villous atrophy and inflame which leads to malabsorption
What are the clinical features of Coeliac disease
- ## Features can occur in the GIT or other parts of the body like mouth
What are the consequences of villous atrophy in coeliac disease
- Growth retardation in children
- Vitamin deficiencies –> anaemia, bleeding tendencies
- Mineral deficiencies - osteomalacia
What are the clinical manifestations of villous atrophy in coeliac disease
- Glossitis
- Burning mouth
- Angular chelitis
- Tiredness
- Malaise
- Easy bruising
What are the clinical manifestations of inflammation in coeliac patients
Crampy abdominal pain and bloating
AY BAWS CAN I HABE DE NOTE PLZ
Theres a small risk of developing GI T cell lymphomas and other malignancies
What are some of the special investigaytions that can be done for coeliac patients
- FBC - iron deficiency anaemia
- Haematinics screen - low vitamin B12, folate, iron
- Stool examination - excess fat
- Serology - IgA antibodies
- Endoscopy - villous atrophy
How are oral lesions relevant to coeliac disease
- Diagnostic importance - CD is often a latent and insidious disease
- Recurrent oral ulceration or dental hyperplasia may be only presenting feature of adults with CD
- Involvement of small bowel mucosa –> reduced absorption of B12, folate and iron
What is a GFD in coeliac
GFD = Gluten Free Diet
What are the clinical features of the oral lesions from coeliac disease i think
- Dental hypoplasia
- Glossitis/burning mouth symptoms
- Angular cheilitis
- Cheilosis/recurrent oral ulceration
- Associated autoimmune disease (sjogrens, DM)
- Malignant disease (oesophageal + oropharyngeal squamous cell carcinoma, small bowel carcinoma)
What are some common non-neoplastic association with coeliac disease
- Dermatitis herpetiformis
- Linera IgA disease
- Selective IgA deficiency
What does dermatitis herpetiformis often present with
- Pruritic vesiculopapular rash
- 70% of patients with this have oral lesions
Is dental hypoplasia common among CD patients
Yes very common in children and adults, usually just mild enamel defects - rough surface with horizontal grooves or shallow pits
What ways can we manage coeliac disease
- GFD for life is the only treatment
- Correct any nutritional deficiencies - vitamin B2, calcium, vitamin D etc
What are the dental aspects to consider in patients with coeliac disease
- early onset coeliac disease = short stature, diarrhoea, enamel defects
- Anaemia may predispose to oral lesions
- Anaemia may complicate general anaesthesia
What are the main functions of the large intestine
- Recovery of water and electrolytes (Na+ and Cl-)
- Formation, storage and expulsion of faeces (stool)
What are some common diseases of the large intestine
Inflammatory bowel diseases:
- Crohn’s disease
- Ulcerative colitis
Describe the morphology of crohn’s disease
- Patchy full thickness ulceration involving any part of GIT from mouth to anus
- Discontinuous involvement - skip lesions
What is the most commonly affected area for Crohn’s disease
The terminal ileum
Describe the histology of crohn’s disease
Transmural granulomatous inflammation
What are the typical clinical features of crohn’s disease
- Fever
- Anorexia
- Abdominal pain
What are some of the clinical features if the mouth is affected by Crohn’s
- Peri-oral and lip swelling
- Mucosa tags or cobblestoning of the mucosa
- Angular stomatitis
- Atypical ulcers - large, linear and ragged
- Recurrent apthous stomatitis
- Lesions associated with nutritional deficiencies
What are some of the clinical features if the small intestine is affected by Crohn’s
- Abdominal pain - appendicitis
- Abnormal bowel habits - diarrhoea and constipation
- Weight loss
- malabsorption
What are some of the clinical features if the Large intestine is affected by Crohn’s
- Non-bloody diarrhoea lasting more than 6 weeks
- Bleeding and pain related to defecation
- Intestinal obstruction due to structuring disease
What are some of the clinical features if the perianal area is affected by Crohn’s
- Anal tags
- Anal fistulae, fissure
- Anal abscess formation
What musculoskeletal system effects can form from Crohn’s disease
- Arthiritis
- Ankylosing spondylitis
What skin effects can form from Crohn’s disease
- Erythema nodosum
- Psoriasis
- Pyoderma gangrenosum
What special investigations can be carried out for Crohn’s disease
- FBC - anaemia, microcytosis, thrombocytosis
- Inflammatory markers - ESR, CRP increased
- Haematinic screen - decreased folate, ferritin, iron studies, B12, potassium, zinc
- Increased faecal calprotectin
- Stool microscopy to exclude infective diarrhoea
What radiological investigations can be done for crohn’s
- Lower GI endoscopy - sigmoidoscopy/colonoscopy
- MRI and CT scanning
- Barium follow through - skip lesions may be identified
What histological investigations can be done for crohn’s
Mucosal biopsies - non caseating granuloma
Describe some of the histological findings in Crohn’s disease
- Inflammed small intestine mucosa
- Granulomatous inflammation
- Ulceration
- Dilated and sclerotic lymphatic channels
What life style management is advised for crohn’s patients
- Stop smoking
- Avoiding stress
- Exercise
- Balanced diet
- Staying well hydrated
What anti-inflammatory drugs are recommended for crohn’s patients
Sulfasalazine/Mesalazine
What immunomodulators might be used in Crohn’s patients
- Prednisolone
- Methotrexate
- Azathioprine
What surgery might be done for Crohn’s patients
- To drain abscesses
- Repair fistulae and fissures and failure to respond to therapy
What biological therapy might be used on Crohn’s patients
Anti-TNFalpha
Infliximab/Adalimumab
What are the dental aspects to consider in Crohn’s patients
- Stressful situations can precipitate an acute disease flare up
- Avoid antibiotics for treatment of oral infections which can aggravate existing diarrhoea
- Always evaluate history of corticosteroid use particularly when major dentistry is anticipated
- Delay routine dentistry during acute flare-up
- Oro-facial granulomatosis (OFG) may precede gastrointestinal manifestation of Crohn’s disease
What layers of the intestinal walls are affected by UC inflammation
The superficial layers
What are the clinical features of UC
- Abdominal pain
- Bloody diarrhoea
- Pus
- Intermixed mucus with/out systemic toxicity
- Systemic toxicity - fever, anorexia, weight loss, anaemia and raised ESR and CRP
Others include:
- Joint pain, conjunctivitis
What is a complication of UC
Carcinoma of the colon
When does pseudomembranous colitis tend to occur
After high doses and/or for prolonged oral antibiotic use
More susceptible in elderly or debilitated patients
What antibiotics tend to be associated with pseudomembranous colitis
Lincomycin and clindamycin
What bacterial proliferation is pseudomembranous colitis associated with
C. Diff
What does pseudomembranous colitis manifest as
Painful diarrhoea and mucus passage in the stool
What is pseudomembranous colitis treated with
Oral metronidazole or Vancomycin
What might the aetiology of irritable bowel syndrome be linked to
- An infection
- Stressful life event
- Anxious personality type
What are the clinical features of IBS
- Patient usually looks healthy
- Crampy abdominal pain relieved by defecation or flatulence
- Bloating or abdominal distension
- Altered bowel habits
- Examination is usually normal
What are the dental aspects of IBS
- Patient may present psychogenic oral symptoms
- Burning mouth syndrome
- Persistent idiopathic facial pain
- Sore tongue
What is Peutz-Jegher’s syndrome and what is it characterised by
Autosomal dominant condition characterised by mucocutaneous hyperpigmentation that present as:
- macules on the lips and buccal mucosa
- Occasional macules circumorally
- Gastrointestinal harmatomatous polyps
What are some complications associated with Peutz-Jegher’s syndrome
- Intestinal obstruction
- Abdominal pain
- Gastrointestinal bleeding
