Gastro Flashcards
Pathophysiology of coeliac disease:
Coeliac disease is a T cell-mediated inflammatory autoimmune disease affecting the small bowel in which sensitivity to prolamin results in villous atrophy and malabsorption.
What allele is associated with coeliac disease?
Associations include positive family history, HLA-DQ2 allele, and other autoimmune diseases (such as type 1 diabetes mellitus).
What allele is associated with coeliac disease?
Associations include positive family history, HLA-DQ2 allele, and other autoimmune diseases (such as type 1 diabetes mellitus).
Rash associated with coeliac disease:
Dermatitis herpetiformis
Presents with pruritic papulovesicular lesions over the buttocks and extensor surfaces of the arms, legs, and trunk).
Investigation of coeliacs:
TTG then refer for OGD jejunal biopsy for gold standard.
Summary of blood tests for coeliacs:
- FBC (this may show microcytic anaemia due to iron deficiency, normocytic anaemia due to chronic inflammation, or macrocytic anaemia due to folate deficiency)
- U&E and bone profile (vitamin D absorption may be impaired)
- LFT (albumin may be low secondary to malabsorption)
- Iron, B12, Folate
Important complications of coeliac disease:
Anaemia
Hyposplenism (and therefore a susceptibility to encapsulated organisms)
Osteoporosis (a DEXA scan may be required)
Enteropathy-associated T cell lymphoma (EATL; a rare type of non-Hodgkin lymphoma).
The likelhood or aquiring this malignancy is directly proportional to the strength of overall adherence to a gluten free diet - i.e. the more a patient breaks adherence, the more likely they are to get EATL.
Diagnosis based on this presentation:
- Bronze skin
- Type 2 diabetes mellitus
- Fatigue
- Joint pain
- Liver cirrhosis
- Adrenal insufficiency
Haemochromatosis
Blood test results in a patients with haemochromatosis:
- Deranged LFTs
- Raised serum ferritin
- Raised transferrin saturation
Low TIBC
Investigations for haemochromatosis:
- Bloods
- Genetic testing can reveal HFE gene defects
- MRI imaging of the brain and heart may show evidence of iron deposition.
- A liver biopsy will show increased iron stores
What gene is associated with haemochromatosis?
HFEC282Y
How to differentiate between biliary colic, acute cholecystitis and ascending cholangitis?
Biliary colic = pain
Acute cholecystitis = pain + fever
Ascending cholangitis = pain + fever + jaundice
What is Murphy’s seen and what is it seen in?
Murphy’s sign on examination: inspiratory arrest upon palpation of the right upper quadrant.
Acute cholecystitis
Management of acute cholecystits?
Ultrasound to diagnose then IV antibiotics, then cholesystectomy for all patients within 1 week.
Prolonged diarrhoea results in what on an ABG?
Prolonged diarrhoea may result in a metabolic acidosis associated with hypokalaemia
Giardia - presentation with diarrhoea and transfer:
Giardia causes fat malabsorption, therefore greasy stool can occur. It is resistant to chlorination, hence risk of transfer in swimming pools.
Features of acute cholecystitis:
- Right upper quadrant pain
- May radiate to the right shoulder
- Fever and signs of systemic upset
- Murphy’s sign on examination: inspiratory arrest upon palpation of the right upper quadrant
- Liver function tests are typically normal
Treatment of acute cholecystitis:
- NICE now recommendearly laparoscopic cholecystectomy, within 1 week of diagnosis.
Also give IV antibiotics.
Boas sign:
Seen in acute cholecystitis.
Boas sign refers to this hyperaesthesia. It occurs because the abdominal wall innervation of this region is from the spinal roots that lie at this level.
Cullen’s sign:
Cullens sign occurs when there has been intraabdominal haemorrage. Seen as bruising over the umbilicus.
It is seen in cases of severe haemorrhagic pancreatitis and is associated with a poor prognosis. It is also seen in other cases of intraabdominal haemorrhage (such as ruptured ectopic pregnancy).
What is 1st line for treating C.diff?
Oral vancomycin
Colicky RUQ abdo pain, worse after fatty foods. Nausea / Vomiting.
Top differential?
Biliary colic
What is Mirizzi syndrome?
A gallstone impacted in the distal cystic duct causing extrinsic compression of the common bile duct.
- LFT’s may be deranged (specifically ALP).
Acute cholecystitis treatment:
IV Antibiotics + cholecystectomy
Ileus
Reduced bowel peristalsis resulting in pseudo-obstruction.
Double duct sign
- what is it, and what’s the diagnosis?
Pancreatic cancer: Double duct sign is due to dilatation of the pancreatic duct and common bile ducts.
Why is bilary colic worst postprandially after a fatty meal?
The classical symptoms are of colicky right upper quadrant pain that occurs postprandially. The symptoms are usually worst following a fatty meal when cholecystokinin levels are highest and gallbladder contraction is maximal.
Risks of ERCP:
- Bleeding 0.9% (rises to 1.5% if sphincterotomy performed)
- Duodenal perforation 0.4%
- Cholangitis 1.1%
- Pancreatitis 1.5%
Patient severely septic and unwell
Jaundice
Right upper quadrant pain
Diagnosis?
Cholangitis
Cholangitis management
Ultrasound is generally used first-line in suspected cases to look for bile duct dilation and bile duct stones.
Fluid resuscitation
Broad-spectrum intravenous antibiotics
Correct any coagulopathy
Early ERCP - to alleviate any obstruction.
Charcot’s triad:
- what is it?
- what condition is it seen in?
RUQ, Fever, Jaundice.
- Seen in acute cholangitis
Reynold’s pentad:
- what is it?
- when is it seen?
Charcot’s triad of RUQ pain, fever, jaundice + hypotension and confusion.
- occurs due to the presence of pus in the biliary ducts.
What is ascending cholangitis?
Ascending cholangitis is a bacterial infection (typically E. coli) of the biliary tree. The most common predisposing factor is gallstones.
What are the 4F’s of risk factors for gallstones?
- Fat: obesity is thought to be a risk factor due to enhanced cholesterol synthesis and secretion
- Female: gallstones are 2-3 times more common in women. Oestrogen increases activity of HMG-CoA reductase
- Fertile: pregnancy is a risk factor
- Forty
- Family History:
- Diabetes and Crohn’s
Gallstone formation occurs because of:
↑ cholesterol, ↓ bile salts and biliary stasis
Complications of gallstones:
- Biliary colic
- Acute cholecystitis: the most common complication
- Ascending cholangitis
- Acute pancreatitis
- Gallstone ileus
- Gallbladder cancer
What is primary sclerosing cholangitis?
Primary sclerosing cholangitis is a biliary disease of unknown aetiology characterised by inflammation and fibrosis of intra and extra-hepatic bile ducts.
What disease does PSC have a relation to?
Ulcerative colitis: 4% of patients with UC have PSC,80% of patients with PSC have UC
- Cholestasis
- Jaundice, pruritus
- Raised bilirubin + ALP
- Right upper quadrant pain
- Fatigue
Diagnosis:
PSC
How should suspected primary scleroising cholangitis be investigated?
- Endoscopic retrograde cholangiopancreatography (ERCP) or magnetic resonance cholangiopancreatography (MRCP) are the standard diagnostic investigations.
- p-ANCA may be positive
- There is a limited role for liver biopsy, which may show fibrous, obliterative cholangitis often described as ‘onion skin’.
What is seen on ERCP in a patient with primary sclerosing cholangitis?
Showing multiple biliary strictures giving a ‘beaded’ appearance.
Complications of primary sclerosing cholangitis:
- Cholangiocarcinoma (in 10%)
- Increased risk of colorectal cancer
How does PSC present?
- Cholestasis
- Jaundice, pruritus
- Raised bilirubin + ALP
- Right upper quadrant pain
- Fatigue
1st line investigation for acute pancreatitis?
Early ultrasound imaging in acute pancreatitis is important to determine the aetiology as this may affect management (e.g. patients with gallstones/biliary obstruction).
Causes of pancreatitis:
I GET SMASHED
- Idiopathic
- Gallstones
- Ethanol
- Trauma
- Steroids
- Mumps(other viruses include Coxsackie B)
- Autoimmune (e.g. polyarteritis nodosa),Ascaris infection
- Scorpion venom
- Hypertriglyceridaemia, Hyperchylomicronaemia, Hypercalcaemia, Hypothermia
- ERCP
- Drugs (azathioprine, mesalazine*, didanosine, bendroflumethiazide, furosemide, pentamidine, steroids, sodium valproate).
How does pancreatitis present?
Patients will classically present with a sudden onset of severe epigastric pain, which can radiate through to the back, with nausea and vomiting.
On examination, there is often epigastric tenderness, with or without guarding. In severe cases, there may be haemodynamically instability, due to the inflammatory response occurring.
Note: Gallstone aetiology may cause an obstructive jaundice.
Investigtions for acute pancreatitis:
- Serum lipase (most specific but expensive)/amylase.
- LFT’s (to look for a cholestatic element).
- Abdominal ultrasound.
- Abdominal CT (used 6-10days into admission) - can show pancreatic oedema and swelling along with pancreatic necrosis.
Patients with acute pancreatitis noted that an alanine transaminase (ALT) level >150U/L has a positive predictive value of 85% for gallstones as the underlying cause.
What is the main scoring system used to assess severity of pancreatitis?
Glasgow Criteria
Note: These can also be used but less commonly APACHE II score, the Ranson Criteria, and Balthazar score (CT scoring system).
When would you use a broad spec antibiotic in acute pancreatitis?
Abroad-spectrum antibiotic, such as imipenem, should be considered for prophylaxis against infection in cases of confirmed pancreatic necrosis.
Summary of acute pancreatitis:
- just read :)
- Most cases of acute pancreatitis are due to either gallstones or alcohol
- Serum amylase 3 times the upper limit of normal is diagnostic of acute pancreatitis.
- Abdominal US scans are used to investigate the potential underlying causes whilst CT scans are only used if complications are suspected or the diagnosis is not certain.
- Treatment is conservative and antibiotics should only be used as prophylaxis in cases of confirmed pancreatic necrosis.
Full C.diff tx
1st line for mild = Oral vancomycin
1st line for severe = oral vancomycin + IV metronidazole
2nd line = Fidaxomicin
Faecal transplant for recurrent infection
Dysphagia to liquids and solids =
Achalasia
How to investigate liver cirrhosis in an alcholic?
LFT’s transient elastography
Painless jaundice with an enlarged gallbladder = ?
Pancreatic cancer
Pseudomembranous colitis is caused by…
c dif
Duodenal ulcers characteristically cause pain when hungry, and are relieved by eating
Duodenal ulcers characteristically cause pain when hungry, and are relieved by eating
IgM
anti-Mitochondrial antibodies, M2 subtype
Middle aged females
Primary biliary cholangitis
Positive IgA and TTG do what test?
Jejunal biopsy
Isolated raised GGT what’s the cause?
Alcohol excess
Isolated raised GGT what’s the cause?
Alcohol excess
Abdo pain + low bicarb + high lactate
Mesenteric ischaemia
Inv for severe UC?
Flexible sigmoidoscopy
In patients with severe colitis, colonoscopy should be avoided due to the risk of perforation - a flexible sigmoidoscopy is preferred
Management for inguinal hernias
Most inguinal hernias are repaired even if they are asymptomatic. This patient appears to be fit enough to undergo surgery
