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Flashcards in Jaundice Deck (15)
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1
Q

Jaundice definition

A

Yellow discolouration of the tissues, noticed especially in the skin and sclera, due to accumulation of bilirubin. Detectable clinically when bilirunin levels >50umol/L (40)

2
Q

Physiology of Bilirubin metabolism

A

Physiology

  • Unconjugated bilirubin formed mainly in spleen by the breakdown of haemoglobin
  • It is soluble and is transported in the plasma bound to albumin
  • Taken up by the liver by active transport, it is converted in the hepatocytes into conjugated bilirubin (water-soluble)
  • It is excreted into the bile canaliculi and via the main bile ducts into the DD
  • Ten percent of the unconjugated bilirubin is reduced to urobilinogen by small intestinal bacteria, reabsorbed in the terminal ileum, and then excreted in the urine (enterohepatic circulation)
  • Ninety percent is converted by colonic bacteria to stercobilinogen which is excreted in faeces
3
Q

Causes of jaundice

A
  • Pre hepatic (Haemolytic jaundice) – unconjugated hyperbilirubinaemia
  • Hepatic (Hepatocellular jaundice) – conjugated or unconjugated hyperbilirubinaemia
  • Post hepatic (Cholestatic (obstructive) jaundice- conjugated hyperbilirubinaemia
4
Q

Pre-hepatic causes

A

Pre-hepatic

  • Congenital abnormalities of red cell structure or content (e.g hereditary spherocytosis, sickle cell)
  • Autoimmune haemolytic anaemia
  • Transfusion reactions
  • Drug toxicity
5
Q

Hepatic causes

A

Hepatic Jaundice

  • Hepatic unconjugated hyperbilirubinaemia
    • Gilberts syndrome (deficiency or abnormalities of unconjugated bilirubin uptake)
    • Crigler-najjar syndrome – abnormality of conjugation process enzymes
  • Hepatic conjugated hyperbilirubinaemia
    • Infection – Viral (e.g hep A,B,C,EBV, CMV), bacterial (liver abscess, leptospirosis), parasitic( amoebic)
    • Drugs e.g paracetamol overdose
    • Non infective hepatitis
6
Q

Post hepatic causes

A

Intraluminal abnormalities of bile ducts

  • Gallstones
  • Blood clot
  • Parasites

Mural abnormalities of bile ducts

  • Cholangiocarcinoma
  • Congenital atresia
  • Sclerosing cholangitis
  • Biliary cirrhosis

Extrinsic compression of bile ducts

  • Pancreatitis
  • Tumours (head of pancreas)
  • Lymphadenopathy of porta hepatitis nodes
7
Q

History

A
  • FH of blood disorders/transfusions
  • Recent foreign travel and work (exposure to infectious agents)
  • Recent drugs or changes in medications
  • Recent surgery or anaesthesia
  • History of gall stones
  • Alcohol intake, cholangitis (pain, fever, rigors) and carcinoma
  • Alcohol and IV drug use
8
Q

Examination of jaundice

A
  • Signs of CLD (spider naevi, palmar erythema, leukonychia, clubbing, gynaecomastia_
  • Hepatic encephalopathy
  • Lymphadenopathy
  • Hepatosplenomegaly
  • Splenomegaly
  • Ascites and palpable gallbladder (cholestatic)
  • Pale stools
  • Dark urine
9
Q

Investigations

A
  • Haematology – FBC, clotting (increased protrhombin),Reticulocytosis, abnormal blood film
  • Chemistry- U and Es, LFT, ALT, AST, Alk Phosp, y-gt, total protein
  • Microbiology- blood and other cultures (leptospiral, and hepatitis A,B,C serology)
  • Immunology (Anti-smooth muscle antiboides), Anti-mitochondrial antibodies (PBC)
  • Urine – Bilirubin is absent in pre-hepatic, in obstructive jaundice, urobilinogen is absent
  • Utralsound – are the bile ducts dilated >6mm, Are there gall stones, hepatic metastses or a pancreatic mass
  • ERCP – if the bile ducts are dilated and LFTs not improving
  • MRCP- if conventional ultrasound shows gallstone but no definite common bile duct stones
  • Liver biopsy- if bile ducts normal
  • CT/MRI if abdomonal malignancy is suspected
10
Q

Treatment of jaundice

A
  • Treat the cause promptly
  • Haemolytic jaundice
    • Steroids for autoimmune case
    • Splenectomy (laproscopic)
  • Obstructive jaundice
    • ERCP and PTC may be used as above for stones, strictures
    • Surgical drainage used for failed interventional treatments
    • Surgical resection- whipples pancreaticduodenectomy
  • Hepatocellular jaundice
    • Remove causative agent
    • Transplant in specific cases
11
Q

Complications of jaundice

A
  • Renal failure (hepatorenal failure) – combination of infection, dehydration and a direct effect of high levels of bilirubin and other toxic products
  • Biliary infection (cholangitis) – obstructive jaundice or previously damaged biliary tree
  • Deranged coagulation – decreased synthesis of vitamin K dependent clotting factors
  • Relative immunisuppresion- predisposes to systemic infections and reduces wound healing due to combinations of jaundice
12
Q

Causes of obstructive jaundice

A
  1. CBD stone
  2. Pancreatic carcinoma (head)
  3. external compression - lymph nodes, large stone in gallbladder neck, metastatic cancer in liver
  4. bile duct cancer- cholangiocarcinoma
  5. congenital bile duct stricture
13
Q

Symptoms of obstructive

A
  1. Jaundice- yellow sclera, skin
  2. dark urine
  3. pale stools
  4. weight loss
  5. itching
14
Q

Investigations of obstructive jaundice

A
  1. Liver function - obstructive picture
  2. coagulation tests
  3. abdominal ultrasound/CT
  4. MRCP
  5. ERCP
15
Q

Treatment of obstructive

A
  • depends on cause
  • bile duct stones (stones often spontaenously pass)

ERCP + stone extraction+ spincterotomy

Surgical exploraiton of bile duct