GI 3 Flashcards
What are the investigations into stools?
FOB testing
Stool culture
Faecal calprotectin
Faecal elastase – investigation of pancreatic insufficiency/malabsorption
How do you screen the liver?
hep B/C serology autoantibodies (ANA, AMA), immunoglobulin Ferritin Alpha 1 antitrypsin Caeuloplasmin, copper Alpha fetoprotine
What is coeliac serology?
Tissue transglutaminase
Endomysial antibody
Check IgA levels
How do you manage a patient with low risk features with rectal bleeding?
Wait and watch for 6 weeks
Then review + refer if deteriorated or persistent
How do you manage a patient with high risk features with rectal bleeding?
Refer
Investigate
How do you investigate bleeding?
Endoscopy (+ biopsy if suspicious) Contrast imaging CT MRI >Whatever is most appropriate
What is important for success in bowel anastomosis?
Tension free Well perfused Well oxygenated Clean surgical site Acceptable systemic state
What are the complications of bowel surgery?
Anaesthetic related Bleeding Sepsis VTE Anastomotic breakdown Small bowel obstruction Wound hernia
What is the acute abdomen?
A combination of symptoms and signs, including abdominal pain,
>which results in a patient being referred for an urgent general surgical opinion
What are the most common causes for acute abdomen?
Non-specific pain Acute appendicitis Acute cholecystitis Peptic ulcer perforation Urinary retention
What are the routes of infection of the peritoneum? (causing peritonitis)
Perforation of GI/ biliary tract
Female genital tract
Penetration of abdominal wall
Haematogenous spread
When does generalised peritonitis occur?
It means localisation has failed and occurs when:
Contamination too rapid
Contamination persists
Abscess ruptures
What are the symptoms of intestinal obstruction?
Pain Vomiting Distension Constipation Borborygmi
What are the types of abdominal pain? (character)
Visceral
Somatic
Referred
If pain comes and goes, what should you consider?
Peritonitic pain
Colic
Body wall pain
What are the aims of resus in regards to acute abdomen?
Restore circulating volume Ensure tissue is perfused Enhance tissue oxygenation Treat sepsis Decompress gut Ensure adequate pain relief
What are the types of viral hepatitis?
A and E (self limiting)
B, C and D are parenteral (cause chronic disease)
How is Hep A transmissible?
Transmission through fecal-oral route, sexual, or blood bourne
What are the features of Hep A?
5-14 commonenst (children affected for shorter, but more common)
Sporadic infection of epidemic
Diagnosed acutely with IgM antibodies
Who is advised to get the Hep A vaccine?
Travellers Patients with chronic liver disease (HBV or HCV especially!) Haemophiliacs Occupational exposure Men who have sex with men
What is the structure of HBV?
Has a surface antigen coat
Inner coat with DNA polymerase
Inside with the core antigen
How does HBV avoid the immune system?
Creates a host of empty cells of surface antigens to confuse body (no inner core)
Sits in liver, but sends decoy antigen into blood (E antigen – HbeAg)
Difference between E antigen and core antigen is the lack of Pre C in code, what allows it to travel into the blood
What do the different HBV antigens indicate? Surface antigen E antigen Core antigen HBV DNA
Surface antigen – presence of virus
Presence of E antigen in blood indicates acute infection (active replication)
Core antigen – active replication (not detectable in blood)
HBV DNA (active replication)
What do the different HBV antibodies indicate? Anti-HBs IgM anti HBc IgG anti HBc Anti HBe
Anti-HBs - protection
IgM anti HBc – acute infection
IgG anti HBc – chronic infection/exposure
Anti HBe – inactive virus
What is the approach to HBV infection?
If HBsAG negative – no active infection, vaccinate
Positive – check if clinical evidence of acute infection
If no evidence, of no IgM anti-HBc then chronic infection
If clinical evidence and IgM anti HBc – acute infection
As acute infection clears in 90% of patients in 6 months, no treatment
Chronic – evaluate for ongoing monitoring and treatment
(Not all patients have chronic disease)
How do you treat chronic HBV?
If the HBV DNA IU/mL >2000, treatment indicated
Normally Tenofovir used, as low rates of resilience, works in HIV co-infected, high potency, category B in pregnancy. However, renal toxicity
What are the other potential agents used for HBV infection?
Other agents – Telbivudine
Entecavir
Adefovir
Lamivudine
What is the natural history of HCV?
Rarely causes acute liver failure Most asymptomatic until chirrotic May have normal LFTs 10% report acute jaundice An RNA virus – so uses DNA-RNA transcriptase which mutates rapidly (deliberately) HIV/alcohol speed up disease
What are the drugs available for HCV?
sofosbuvir + ledipasvir
What is HDV?
A small RNA virus that doess not code for own protein coat, enveloped by HBsAg
Co infection or superinfection with HBV (same transmission)
Very resistant to treatment
Parasite of HBV
What is HEV?
Commonest cause of acute hepatitis in Grampian
Self-limiting
No specific treatment
No vaccine
Tropical Zoonotic virus (transmitted by animals, E - via pigs)
What does non-alcoholic liver disease encompass?
Simple steatosis
Non alcoholic steatohepatitis
Fibrosis and cirrhosis
What is NAFLD associated with?
Diabetes mellitus Obesity Hypertriglyceridemia Hypertension Age Ethnicity (Hispanics) Genetics (PNPLA3 gene)
What is the progression of NAFLD?
Normal
- -> steatosis
- -> NASH +/- fibrosis
- -> cirrhosis
How do you diagnose NAFLD?
AST/A:T ratio USS Fibroscan Liver biopsy NAFLD tool on website
How do you treat NAFLD?
Diet and weight reduction (+/- surgery)
Exercise
Insulin sensitisers
Glucagon-like peptide 1 (GLP1) analogues (Liraglutide)
Farnesoid X nuclear receptor ligand (obeticholic acid)
Vitamin E
What are the autoimmune diseases of the liver/biliary tract?
Autoimmune hepatitis Primary biliary cholangitis (PBC) Primary sclerosing cholangitis (PSC) Overlap syndromes Autoimmune cholangiopathy IgG 4 disease
What is autoimmune hepatitis?
Female predominant Elevated IgG Diagnosed by liver biopsy Responds well to steroids Long term azathioprine 3 types of antibodies; Type 1 – ANA, SMA. Type 2: LKM1. Type 3 SLA
Who is eligible for a liver transplant?
Chronic liver diseases with poor predictive survival or poor quality of life
Hepatocellular carcinoma
Acute liver failure
Genetic diseases – primary oxaluria, tyrosemia
What are the contraindications for liver transplant?
Active extrahepatic malignancy
Hepatic malignancy with macrovascular or diffuse tumour invasion
Active and uncontrolled infection outside of hepatobiliary system
Active substance or alcohol abuse
Severe cardiopulmonary or other comorbid conditions
Psychosocial factors that would preclude recovery
Technical/anatomical barriers
Brain death
How is liver transplant prioritised in cirrhosis?
Child’s Pugh scoring A, B, C
MELD score (Bilirubin, Creatinine and INR)
UKELD( Bilirubin, Sodium, Creatinine and INR)
What is the post op treatment for a liver transplant?
Post operative ICU care
Multidisciplinary care
Prophylactic antibiotics and anti-fungal drugs
Anti-rejection drugs: Steroids, Azathioprine, Tacrolimus/Cyclosporine
What can cause acute liver injury?
Hepatitis
Bile duct obstruction
What is the pathophysiology of jaundice?
Increased circulation of bilirubin
Caused by altered metabolism on bilirubin
Pathway can be pre hepatic, hepatic, or post hepatic
What is prehepatic metabolism (bilirubin pathway)?
Breakdown of haemoglobin in spleen to form haem and globin
Haem converted to bilirubin
Release of bilirubin into circulation
What is hepatic metabolism of bilirubin?
Uptake of bilirubin by hepatocytes
Conjugation of bilirubin hepatocytes
Excretion of conjugated bilirubin into biliary system
What is post hepatic metabolism of bilirubin?
Transport of conjugated bilirubin in biliary system
Breakdown of bilirubin conjugate in intestine
Re-absorption bilirubin – entero-hepatic circulation of bilirubin
What causes prehepatic jaundice?
increased release of haemoglobin from red cells – haemolysis
What causes hepatic jaundice?
cholestasis (accumulation of bile within hepatocytes or bile canaliculi)
Intra-hepatic bile duct obstruction
What causes post-hepatic jaundice?
cholelithiasis
Disease of gall bladder
Extra hepatic duct obstruction
What are the causes of cholestasis
What are the causes of cholestasis?
Viral hepatitis
Alcoholic hepatitis
Liver failure
Drugs – therapeutic/recreational predictable v unpredictable (dose vs other factors)
What are the causes of intra-hepatic bile duct obstruction?
Primary biliary cholangitis
Primary sclerosing cholangitis
Tumours of liver – hepatocellular carcinoma, tumours of intra-hepatic bile ducts and metastatic tumours
What is primary biliary cholangitis?
Organ specific auto immune disease (mainly females)
Anti-mitochondrial antibodies in serum
Raised serum alkaline phosphates
Granulomatous inflammation involving bile ducts
Loss of intra-hepatic bile ducts
Progression to cirrhosis
What is primary sclerosing cholangitis?
Chronic inflammation and fibrous obliteration of bile ducts Loss of intra-hepatic bile ducts Assoc. w/ inflammatory bowel disease Progression to cirrhosis Increased risk of developing cholangiocatcinoma Male predominant Recurrant cholangitis, Jaundice Liver Tx, Biliary stents to treat
What are the causes of cirrhosis?
Alcohol Hepatitis B, C Immune mediated liver disease >Auto-immune hepatitis >Primary biliary cholangitis Metabolic disorders (excess iron - primary haemochromatosis >Excess copper – wilsons disease Obesity – diabetes mellitus
What is the pathology of cirrhosis?
Involves whole liver – loss of normal liver structure
Replaced by nodules of hepatocytes and fibrous tissue
What complications can arise from cirrhosis?
altered liver function so failure
Abnormal blood flow – portal hypertension
Increased risk of hepatocellular carcinoma
What are the risk factors for gallstones?
obesity, diabetes, female Cholesterol Parity + OCP Bile infection
What is the pathology of gallstones?
Caused by inflammation (acute/chronic cholecystitis)
Acute – empyema (perforation of gall bladder, biliary peritonitis)
May lead to chronic – causes fibrosis as well as inflammation
What leads to bileduct obstruction?
Gallstones
Bile duct tumours
Benign stricture
External compression – tumours
What are teh effects of bilestone obstruction?
Jaundice
No bile in duodenum
Infection of bile proximal to obstruction (ascending cholangitis)
Secondary biliary cirrhosis if obstruction prolonged)
What is the presentation of gallstones?
Majority asymptomatic Dyspeptic symptoms Biliary colic Acute cholecytitis Empyema Perforation Jaundice Gallstone ileus
What is choledocho-iliasis, what can it lead to?
Blockage of bile duct
Can lead to obstructive jaundice (painful)
Can lead to acute pancreatitis
Can lead to ascending cholangitis
How do you investigate suspected gallstones?
Blood tests – amylase, lipase, WCC, LFTs: AST/ALT,ALP USS, EUS Oral cholecystography CT scan, radio-isotope scan IV cholangiography MRCP/ERCP PTC
How do you manage gallstones?
Asymptomatic – do nothing
Non-operative treatment – dissolution, lithotripsy
Operative
>Cholecystectomy - remove gallbladder, laproscopic gold standard
What are the causes of benign biliary tract disease?
Congenital:
>biliary atresia
>Choledochal cysts
Benign biliary stricture
What tumours can cause jaundice?
Cholangiocarcinoma (intra or extrahepatic, gallbladder, ampullary)
Cancer of head of pancreas
What are the tisks of cholangiocarcinoma?
(Bileduct cancer) PSC (strong association) Congenital cystic disease Biliary-enteric drainage Thorotrast (contrast) Hepatolithiasis Carcinigens: aflatoxins, etc.
What is the presentation of cholangiocarcinoma?
Obstructive jaundice
Itching
Non-specific symptoms
What are the three types oc cholangiocarcinoma?
Mass forming (blockage)
Peri-ductal (both sides)
Intra-ductal (one side)
How do you manage cholagiocarcinoma?
Surgical – only potential cure
Palliative – surgical bypass Stenting Radiotherapy Chemo PDT
How do you treat an ampullary tumour?
Depends if adenoma or adenocarcinoma Treatment: Endoscopic excision Trans-duodenal excision Pancreatico-duodenectomy
What are the liver function tests?
Bilirubin Aminotransferases Alkaline phosphatase Gamma GT Albumin Prothombin time Creatine Platelet count
What are aminotransferases?
enzymes in hepatocytes –
>ALT more specific than AST.
>AST/ALT ratio points towards ALD
>suggests parenchymal involvement)
What is alkaline phosphatase (ALP)?
enzyme in bile ducts,
elevated with obstruction or liver infiltration.
>Also present in bone, placenta and intestines
What is Gamma GT?
A non specific liver test
Elevated in alcohol, however
>Useful to confirm ALP result
What does low albumin indicate?
suggest chronic liver disease,
>can be low in kidney disorders and malnutrition
Why is prothrombin time important?
Tells extent of liver damage
Why is creatine important as a liver test?
It is essentially kidney function
>Used to determine survival from liver disease
Why is platlet count a liver test? What do low levels indicate?
liver produces thromboprotein
>cirrhosis in splenomegaly
Platelets low in cirrhotic patients (hypersplenism) >Indirect marker of portal hypertension
What are the symptoms of liver failure?
Jaundice,
ascites,
variceal bleeding,
hepatic encephalopathy
What are the clues for pre-hepatic jaundice?
Clinical:
Pallor
Splenomegaly
History:
anaemia (fatigue, dyspnoea, chest pain), acholuric jaundice
What are the clues for hepatic jaundice?
Clinical: Ascities, asterixis, stigmata of CLD >(spider naevi, gynaecomastia)
History: risk factors for liver disease >(IVDU, drug intake), decompensation >(ascities, variceal bleed, encephalopathy)
What are the clues for post-hepatic jaundice?
Clinical:
palpable gall bladder (courvoisier’s sign)
History:
abdominal pain,
cholestasis
>(puritus, pale stools, con. Urine)
What can therapeutic ERCP be used for?
Dilated biliary tree (w/ or w/o visible stones/tumour)
Acute gallstone pancreatits
Stenting of biliary tract obstruction
Post-op biliary complications
What complications can arise from ERCP?
Sedation related Procedure related >pancreatitis, >cholangitis, >sphincterotomy - >bleed/ perforation
What is chronic liver disease?
Liver disease lasting more than 6 months: Chronic hepatitis Chronic cholestasis Fibrosis and cirrhosis Others – steatosis Liver tumours
How does compensated chronic liver disease present?
Routinely detected on screening tests
Abnormality of liver function tests
How does decompensated liver disease present?
Ascites
Variceal bleeding
Hepatic encephalopathy
What are the clinical features of ascites?
Physical exam reveals dullness in flanks and shifting dullness Can be confirmed by U/S Corroborating evidence >JVP elevation >Spiders, >palmar erythema, >abdominal veins, >fetor hepaticus >Unbilical nodule >Flank haematoma
How do you confirm ascites?
Protein and albumin concentration
Cell count and differential
Routine – cell count, protein, albumin
What does a SAAG score of >1.1 mean?
SAAG (serum ascites albumin gradient) >1.1g/dl portal HTN related
What does a SAAG score of <1.1 mean?
<1.1g/dl nonportal HTN causes (both 97% acc)
What are the causes of a SAAG score >1.1g/Dl
Portal hypertension CHF Constrictive pericarditis Budd Chiarri Myxedema Massive liver metastases
What are the causes of a SAAG score <1.1g/Dl
Malignancy Tuberculosis Chylous ascites Pancreatic Biliary ascites Nephrotic syndrome Serositis
How do you treat ascites?
Diuretics Large volume paracentesis TIPS Aquaretics Liver transplant
What is variceal haemorrhage?
When an acites bleeds due to portal hypertension. Occur at porto-systemic anastomoses Skin – caput medusa Oesophageal and gastric Rectal Posterior abdominal wall Stomal A medical emergency!
How do you treat variceal haemorrhage?
Resuscitate patient Good IV access Blood transfusion as required Emergency endoscopy - Band ligation Add terlipressin for control Sengstaken-blakemore tube for uncontrolledbleeding TIPSS for rebleeding after banding
What is hpatic encephalopathy?
Confusion due to liver disease
Graded 1-4: confusion to coma
How does hepatocellular carcinoma present?
Decompensation of liver disease Abdominal mass Abdominal pain Weight loss Bleeding from tumour
How do you diagnose hepatocellular carcinoma?
Tumour markers – AFP
Radiological tests – U/S, CT, MRI
Liver biopsy rarely
How do you treat hepatocellular carcinoma?
Hepatic resection Liver transplant Chemo – locally delivered or systemic Locally ablative treatmetns – alcohol injection, radiofrequency ablation Sorafenib (tyrosinase kinase inhibitor) Hormonal therapy – tamoxifen
