How to read(LFT) Liver function tests شرح بالعربى Table of Contents: 00:30 - Introduction 01:25 - Liver Functions 02:53 - Aims of using LFT 04:45 - Elements of LFT 21:11 - Patterns of abnormal LFT 23:24 - 1-Hepatocellular damage pattern 26:04 - 2-Cholestatic pattern 27:47 - 3-Asymptomatic Abnormal LFT 40:00 - 4-Chronic liver diseases and LFT 41:53 - Conclusion شرح بالعربى-LIVER FUNCTION TESTS (LFT)FOR MEDICAL AND NURSING STUDENTS Liver Function Tests Explained for Medical and Nursing Students Aims of LFT in patients with suspected liver disease include: 1-Detect hepatic abnormality 2- Detect the pattern of liver function test abnormality: hepatitic or obstructive/cholestatic 3-Measure the severity of liver damage 4- Identify the specific cause 5- Investigate possible complications Elements of LFTs incclude: Synthetic functions: Serum albumin, Prothrombin time-PT- and bilirubin Markers of liver cell damage: AminotransferasesALT &AST Alkaline phosphatase ALP, γ -glutamyl transferase-GGT- Albumin represents half of the total protein content -3.5 g/dL to 5 g/dL- of plasma . Albumin is synthesized by liver hepatocytes and rapidly excreted into the blood stream at the rate of about 10 gm to 15 gm per day. It functions as a modulator of plasma oncotic pressure and a transporter of endogenous and exogenous i.e. drugs ligands Since the plasma half-life of albumin is about 2 weeks, albumin levels may be normal in acute liver failure but are almost always reduced in chronic liver failure. The coagulation factors proteins are manufactured by the liver. Production of ALT outside the liver is relatively low and this enzyme is therefore considered more specific for hepatocellular damage.
ALP enzymes in the liver are located in cell membranes of the hepatic sinusoids and the biliary canaliculi. Accordingly, levels rise with intrahepatic and extrahepatic biliary obstruction and with sinusoidal obstruction, as occurs in infiltrative liver disease. γ -glutamyl transferase is produced by hepatocytes and by the epithelium lining small bile ducts. The pattern of a modest increase in AST AND ALT activity and large increases in ALP and GGT activity favours biliary obstruction and is commonly described as ‘cholestatic’ or ‘obstructive Patterns of abnormal LFT 1- Hepatocellular injury ALT/AST +/− bilirubin+ALP- 2- Cholestasis ALP +/− bilirubin+ALT & AST 3-Asymptomatic Abnormal Liver function Tests A-Isolated hyperbilirubinemia B-Isolated rise of transaminases. 4-Chronic Liver disease 1-Hepatocellular Injury Elevations in aspartate aminotransferase -AST- and alanine aminotransferase -ALT- higher than ALP rise suggest hepatocellular injury, 2-Cholestatic Predominant elevation in alkaline phosphatase ALP are referred to as cholestatic. 3-Asymptomatic Abnormal Liver function Tests.
Gilbert’s syndrome
In the liver, Uridine 5'-diphospho-glucuronosyl transferase-UDP-conjugates the unconjugated bilirubin with glucuronic acid into conjugated
