The liver is the largest gland in the human body, being a voluminous parenchymatous organ with a weight ranging from 1200 to 1500 mg.
Like the pancreas, it has an exocrine function and endocrine function, but, unlike it, a single cell, the hepatocyte, is responsible for both exocrine secretion and endocrine secretion. The hepatic cell provides the synthesis of plasma proteins, lipoproteins, glucose, fatty acids, cholesterol and phospholipids, synthesis of bile acids, metabolization and detoxification of endogenous and exogenous substances.
The liver fulfils a number of very important roles in the body: purification, detoxification, bile secretion necessary for intestinal digestion, having a decisive role in achieving synthesis processes, namely the degradation and storage of organic and inorganic substances absorbed in the intestine.
To evaluate liver status, a number of standard laboratories analyses are required as the first stage, the most relevant being transaminases TGO and TGP.
TGO (AST) is present in the liver but also in the brain and myocardium. Increases of 10-100 times over normal values occur in acute viral hepatitis, moderate increases occur in chronic hepatitis, hepatic cirrhosis, mechanical icterus, but also in infarct and muscle trauma.
TGP (ALT) is found only in the liver, an increase in the values of this enzyme being associated with acute or chronic hepatitis, liver cirrhosis or mechanical icterus.
Any increase in transaminases requires further tests to find the exact cause.
GGT is an enzyme present in both the liver and the bile ducts. It appears in protein synthesis and its growth occurs in bile retention, chronic hepatitis, primary or metastatic hepatic cancer, hepatic steatosis, in alcoholics or after medication.
Alkaline phosphatase consists of a group of enzymes and its growth occurs in mechanical icterus, cholestatic hepatitis, cirrhosis and liver tumours.
For the full evaluation of liver function, serum bilirubin, total protein, albumin, urea, and creatinine are recommended.
Total bilirubin increases over 1.5 mg/dl - hyperbilirubinemia - shows increased bilirubin production or impaired hepatic metabolization. Total bilirubin is divided into two fractions: direct or conjugated bilirubin and indirect or unconjugated bilirubin.
Bilirubin increases in various liver disorders, namely acute or chronic hepatitis, liver cirrhosis, hepatic tumours, in case of medication.
Jaundice, or the yellow coloration of the teguments, sclera and mucous membranes, occurs when total bilirubin exceeds 2-3 mg/dl.
In addition to laboratory tests, an abdominal ultrasound, which should be routinely performed at 6 months or yearly, has a determinant role in liver evaluation.
Following the ultrasound examination, intrahepatic space substitution formations can be detected, diagnosis of liver steatosis (fatty liver), chronic hepatopathy and liver cirrhosis can be made.
When the fatty liver decelerates, additional tests are required, namely routine laboratory and fibroscan tests.
Fibroscan is a non-invasive, rapid imaging exploration with an on-site result that successfully replaces liver biopsy in diffuse liver diseases: alcoholic or non-alcoholic steatohepatitis, hepatic steatosis, chronic hepatitis and cirrhosis. No pre-training required.
It is done using an ultrasound-like device, with the patient lying on the bed face up and in the left lateral decubitus position, while the doctor examines the liver by placing the transducer in the intercostal area. This investigation measures the elasticity of the liver, as the liver is harder, the higher the degree of fibrosis.
The liver biopsy is an invasive manoeuvre performed under local anaesthesia with special needles for the extraction of one or more liver fragments which will then be analysed by histological examination and/or immunohistochemical examination.
The liver biopsy is the gold standard in the evaluation of intrahepatic tumour formations, but it is successfully replaced by fibroscan, with equally conclusive results in extensive studies and with less risks, in the case of diffuse liver disorders (steatosis, hepatic fibrosis, chronic hepatitis, liver cirrhosis).
The liver exploration is continued through complex imaging examinations, computer tomography and abdominal MRI, when previous explorations are not conclusive or for remote monitoring of intrahepatic space substitution formations.
Liver check-up at least once a year is recommended for all ages up to 40 years. After this age, a check-up is recommended at least once every 6 months.
In the case of people with liver diseases, the check-up should be done according to the doctor's instructions.