Liver Disease Flashcards
what are the causes of NAFLD?
- Unknown
- Associated with metabolic syndromes
- Associated factors: obesity, hyperlipidaemia, type 2 diabetes, jejunoileal bypass, sudden weight loss/starvation
what are the clinical features of NAFLD?
• Usually asymptomatic • Hepatomegally o Steatosis = greasy, yellow, soft o Cirrhosis = bumpy • ALT is usually greater AST • Inceased echogenicity on US
what is the management of NAFLD?
lifestyle
what is the spectrum of disease in NAFLD?
o Steatosis = fat in liver
o Steatohepatitis = fat with inflammation
o Progress to fibrosis + liver cirrhosis
what is the “first step” in NAFLD?
steatosis
how does steatosis occur?
o Insulin resistance causes increased fat storage and decreased fatty acid oxidation
o = decreased secretion of fatty acids into bloodsteream, increased synthesis and uptake of free fatty acids from blood
o Causes fat droplets to form + grow in heaptocytes, some of which become large enough for hepatocytes to swell + nuclei
what is the second hit in NAFLD?
STEATOHEPATITIS
how does steatohepatitis occur?
o Oxidative stress + lipid peroxidation – unsaturated fatty acids react with hydroxyl radical forming water and a fatty acid radical – reacts with non radicals
o Process causes damage of lipid membrane = cell death
o Proinflam cytokine release = TNFa, TGFb, 17B-estradiol
o Presence of Mallory denk bodies = intermediate filaments
what is liver cirrhosis?
• consequence of chronic hepatic injury with healing by regeneration and fibrosis
what are the toxin related causes of liver cirrhosis?
alcohol
what are the infectious causes of liver cirrhosis?
hepatitis B, hepatitis C
what are the autoimmune causes of liver cirrhosis?
o Autoimmune chronic acute liver disease
o Primary biliary cirrhosis
o Primary sclerosing cholangitis
what are the metabolic causes of liver cirrhosis?
o Non alcoholic fatty liver disease
o Iron overload – haemochromatosis
o Copper overload – Wilson’s disease
o A1-antitrypsin associated liver disease
what are the hepatic venous outflow obstructive causes of liver cirrhosis?
o Budd-Chiari syndrome
o Sebere chronic congestive cardiac failure
what are the other causes of liver cirrhosis?
o Secondary to prolonged biliary obstruction
o Cystic fibrosis
o Cryptogenic
o Parental nutrition related
what are the consequences of liver cirrhosis?
- Hepatocellular failure
- Portal hypertension
- Ascites due to portal hypertension
- Malignant change: hepatocellular carcinoma
what are the features of hepatocellular failure in liver cirrhosi
o Impaired protein synthesis: prolonged prothrombin time and low albumin
o Impaired metabolism of toxins: encephalopathy
o Impaired bilirubin metabolism: jaundice
what are examples of benign liver neoplasms?
- Haemangioma
- Adenoma
- Focal Nodular Hyperplasia
what are examples of primary malignant liver neoplasms?
o Hepatocellular carcinoma
o Fibrolamellar carcinoma
o Cholangiocarcinoma
what are examples of secondary malignant liver neoplasms?
o Portal spread
o Systemic blood spread
o Direct spread (from gallbladder, stomach, and hepatic flexure of colon)
what is the cause of liver hemangiomas?
congenital
what is the pathophysiology of haemangioma?
hypervascular tumour of hepatic endothelial cells of blood vessels
what are the clinical features of haemangiomas?
usually asymptomatic, small lesions <1.5xn
how are haemangiomas diagnosed?
US, CT, MRI
