Biochemical Exploration of the Liver PDF

BIOCHEMICAL EXPLORATION OF THE LIVER  EXPLORATION OF THE LIVER ◼ The liver is sensitive to a wide range of metabolic, toxic, microbial, circulatory and neoplastic aggressions. Sometimes the liver damage is primary (eg viral hepatitis or hepatocellular carcinoma), but in mos...

BIOCHEMICAL EXPLORATION OF THE LIVER  EXPLORATION OF THE LIVER ◼ The liver is sensitive to a wide range of metabolic, toxic, microbial, circulatory and neoplastic aggressions. Sometimes the liver damage is primary (eg viral hepatitis or hepatocellular carcinoma), but in most cases the involvement of the liver is secondary to diseases such as decompensated heart failure, metastatic cancer, alcoholism or extrahepatic infections. ◼ The vast functional reserve of the liver determines a certain latency in the clinical expression of early liver lesions. ◼ But with the expansion of the pathological process, the liver functional imbalance can cause life-threatening consequences. 1. Alteration of carbohydrate metabolism The important role of the liver in glucose homeostasis means that severe hepatopathies affect both glucose production mechanisms: - glycogenolysis, - gluconeogenesis, as well as the mechanisms of its use: - glycogenogenesis, - triglyceride synthesis, causing either hypoglycemia or hyperglycemia or glucose intolerance. Glycogen ↓ in cirrhosis ← ↓ the number and volume of liver cells, alcoholism ← ↓ glucose intake. Hypoglycemia ← ↓GLUCONEOGENESIS + ↓ glycogen reserves. ◼ less common in cirrhotics, ◼ more associated with malnutrition and alcohol abuse. ◼ alcohol inhibits GLUCONEOGENESIS ←↓ the incorporation of lactate and ALA into glucose. ◼ only in the depletion of glycogen stores, with depressed GLUCONEOGENESIS. ◼ ↓ hepatic glycogen reserve ← destroy hepatocytes > than ↓ the glycogen in each cell. ◼ massive liver necrosis → fulminant hepatitis → hypoglycemia → death Cirrhotics are also found to have: - ↓ glucose precursors, galactose being metabolized into glucose more slowly, and fructose also being eliminated more slowly from the circulation; - alteration of GNG from proteins or lipids; - alteration of glucose oxidation in 6-phosphogluconate, the liver being unable to catabolize the products resulting from glycolysis → in the blood: ↑lactic acid, pyruvic acid, ketoglutaric acid, simultaneously with - ↓ synthesis of the reduced tripyridine nucleotide (TPNH). Hyperglycemia, with ↓TGO, associated with N/↑ insulinemia, it is more frequent by: - alteration of the receptor, - ↑ Free fatty acids as a result of the intensification of lipolysis, - ↓ blood K+ (which inhibits cellular glucose uptake and ↓ insulin synthesis).  The pathogenetic mechanisms of hepatogenic diabetes are: - hyperinsulinemia, - resistance to exogenous insulin - mechanism more frequently involved than insulin deficiency, - ↑ STH - ↑ glucagon, more through excessive secretion than through its ↓ metabolization, - destruction of the hepatocyte mass.  2. Alteration of lipid metabolism ◼ In metabolic deficiencies, lipids → liver as TRIGLICERIDE → hepatic steatosis. ◼ The liver incorporates the excess of fatty acids into prebeta-LP/→ ketone bodies. ◼ When ketonemia >70mg/dl → the capacity of the tissues (striated skeletal and myocardial) to use ketone bodies is exceeded → hyperketonemia. ◼ Ethanol and Prednisone ↑ lipolysis + release of ALP. ◼ In severe liver failure ↓ cholesterol synthesis ◼ hypercholesterolemia occurs in cholestasis ←↓ of its elimination through the bile. ◼ ± ↓synthesis of bile acids →↓ glucuronic acid/taurocholic acid. ◼ In mechanical jaundice ↑ concentration of bile salts in the blood ± hypocalcemia with hypocoagulability and hemorrhages due to the binding of bile salts to calcium ions.  3. Alteration of protein metabolism In chronic hepatopathy, it is also severe in liver cirrhosis ↓ the angiotensinal concentration of albumins by: - ↓ synthesis, - dilution, - altering the distribution, or - ↑ their catabolism. The majority of degraded albumins → gastrointestinal tract. The liver also plays an important role in the synthesis of globulins, with the preponderance of alpha and beta fractions. In chronic alpha and beta hepatitis globulins ↑- persistent forms ↑↑ - aggressive and cirrhotic forms lympho-plasmacytic infiltration → hypergammaglobulinemia The high values are the consequence: - ↑ their synthesis at the level of the activated hepatic mesenchyme, in an increased proportion and - delays in their catabolism, to a low measure. Plasmatic colloid - osmotic pressure →​​ NV ←↑ globulins, compensatory ↓albumin → prevents ascites. Normally, hepatocytes do not contain gamma-globulins. body's proteins - permanent → AA → reused in situ / released into the blood ↓ liver / other tissues that synthesize proteins In liver necrosis ↓ utilization of AA → ↑↑ blood AA → excreted in urine (LEU/TYR crystals) In the liver, urea ← 4 AA: ornithine, citrulline, arginine and aspartic acid. enzymes from the urea cycle are found →↓ synthesis of urea nitrogen →↓ sanguine concentration.  4. Disturbance of the coagulation mechanism In chronic liver diseases, a state of hypocoagulability is determined by: - ↓ synthesis of coagulation factors : fibrinogen and prothrombin complex (factors II, VII, IX, X ) due to hepatocellular insufficiency (hepatoprivy syndrome); - ↑ the level of coagulation factors; - production of modified coagulation factors; - vitamin K deficiency through malabsorption of fat-soluble vitamins ← a degree of biliary obstruction; - ↓ no. of platelets ← hypersplenism and their alteration; - fibrinolysis ← ↑ blood concentration of plasmins; - vascular fragility. In some cases - ↑concentration of clotting factors, BUT? role in the coagulation deficit. ± ↓ factor I or V, BUT have a low sensitivity in the evaluation of hepatocytic insufficiency. In severe liver diseases (advanced liver cirrhosis), hemorrhagic syndrome: - ↓ the synthesis of coagulation factors and - ↑ their use in CID/excessive fibrinolysis. In chronic liver diseases, factors XI, XII, XIII only appears = ↓ Enable VIII is rarely low. In liver diseases, the decrease in activity is also evident: - antithrombin II, - antithrombin III, - antiplasmins. Increased consumption of coagulation factors in hepatopathies: - disseminated intravascular coagulation; - excessive fibrinolysis; - proteolysis, or - inhibition of various coagulation factors. CID - ↑ thromboplastin ← circulation secondary to hepatocyte injury, - the insufficiency of the hepatic clearance mechanism. Thrombin forms and enters the vasculature , consuming clotting factors → hemorrhages. Degradation products of fibrin ← initiation of fibrinolysis by CID, - have the ability to inhibit coagulation. In CID, the following are depressed: - coagulation factors II, V, VIII, XIII; - platelets; - plasminogen; - antithrombin and - antiplasmin. Thrombocytopenia is due to: - hypersplenism, - deficient megakaryopoiesis, - CID or - immune thrombocytolysis. Platelets can also undergo changes in aggregation and adhesion (thrombasthenia) Fibrinolysis - rare in general; in hepatopathies → excessive in the majority of cirrhotics. In severe hepatocellular diseases → abnormal fibrinogen →↑ QT and thrombin. Vitamin K deficiency ← ↓ hepatocyte synthesis.  5. Disturbance of the function of secretion and excretion of bile The lesions that affect the secretion and excretion of bile in hepatopathies have multiple locations, affecting: - microsomal biotransfer system, which interferes with the metabolism of bile acids, - hepatocyte membrane, - desmosomes, - canalicular membrane and canalicular ectoplasm, - inflamed bile canaliculi. As a result of these injuries, increased amounts of: - bilirubin, with the predominance of direct bilirubin, - bile acids, - cholestasis enzyme - ALP, 5-nucleotidase, GGT, LAP - cytolysis enzyme - AT ← excess bile salts damage the hepatocytic membrane. Clinical manifestation - jaundice; metabolic disorders, occurs in: - capture, - conjugation or/and - pigment excretion. Alteration of the bilirubin capture stage (alteration of BSP clearance) rarely as an isolated mechanism to a reduced extent in the case of liver cell damage; in the majority of cases it is associated with another alteration of the hepatic metabolism of bilirubin. Gilbert syndrome - the mechanism ← associations conjugation deficiency (hypoactivity of hepatocyte UDP-glucuronyl-transferase) with the one of hepatic capture of bilirubin (alteration of BSP clearance)  Alteration of the conjugation stage of bilirubin it is caused by a deficient activity of the microsomal UDP-glucuronyl-transferase. ↑ blood level of unconjugated bilirubin → deposits in skin and mucous enzyme deficiency can be: - congenital (Gilbert syndrome, Crigler-Najjar syndrome), acquired (drugs , Hepatocyte lesions caused by infectious / toxic agents ). alteration of glucuronide conjugation can act either: - isolated in the case of congenital enzyme deficiencies, - associated with other mechanisms, especially in toxic / infectious hepatopathies.  Alteration of the hepatocytic excretion stage of bilirubin In the vast majority of cases, it is associated with mixed hyperbilirubinemia, mainly the conjugated fraction. transport of bilirubin → the bile pole of the cell and its excretion is affected The mechanism occurs in diseases: - inheritance – Sd. Dubin-Johnson, Sd. Rotor, Sd. summerskill, - acquired - medications, postoperative, acute and chronic hepatitis, liver cirrhosis.  6. Disturbance of the clearance and detoxification function The liver occupies the central place in the detoxification of numerous substances: - endogenous – hormones, ammonia, bilirubin, - exogenous (xenobiotics) – drugs, toxic. Pathological changes of the affected liver. and the antitoxic function, provided by both: - the parenchyma, as well as of - hepatic mesenchyme. The toxic syndrome is due to: the loss by the liver cell of the ability to: - neutralizes and eliminates natural catabolic and exogenous toxic residues , - ensures the full development activity reduction - macrophages and - to the other cells ← the systemic derivation of the portal angel. In liver failure, ↑NH3 in the blood → CNS toxic → seizures → ± death. ↑NH3 →↑ synthesis of GLU in the nerve cell, a process that requires ATP (W) - subtracted from other fundamental neuron biosynthesis processes. Regarding drug metabolism, they are modified differently in chronic hepatopathies; in the vast majority, oxidations are earlier affected than conjugations. The levels of impairment of the pharmacokinetics of drugs are: - intrinsic hepatic clearance for a given substance, - hepatic circulation, - the presence of a portocaval shunt and - fixation of plasma proteins. 3 types of reaction in the liver: 1) interference with bilirubin metabolism, leading to - hemolysis - export of quinine, phenacetin, sulfamide, penicillin; - affect the binding of bilirubin in white blood cells, through competitive transport - export of aspirin, biseptol; - altered bilirubin conjugation​ - export of novobiocin, which inhibits glucuronyl-transferase; - change in bile excretion and intrahepatic cholestasis - export of chlorpromazine, methyltestosterone; 2) direct hepatotoxicity, what determines - hepatocytic necrosis - typical example for: CCl4, halothane, chloroform, DDT, TNT, amanita phalloides, antimitotics (methotrexate, 6-mercaptopurine, imuran), even paracetamol or salicylates; - hepatic steatosis with minimal inflammatory infiltrate; - hepatocellular jaundice; - death in 25% of cases ← hepatic necrosis + associated injuries (renal, nervous); 3) medicinal enzyme induction - beneficial effect - example: phenobarbital (and even alcohol).  7. Disorders in hormone metabolism The liver plays an important role in the metabolism of hormones, especially steroids. Hormonal disorders ← affecting their catabolism - hyperestrogenism - hypercorticism ← insufficient inactivation of CSR hormones; - Hyperaldosteronism ← excess secretion ←↑ angiotensin ↓hepatic clearance; - ↓catabolization of 17-HO-steroids into 17-ketosteroids →↓androgen synthesis → secondary feminization phenomena; - hyperthyroxinemia (thyroxine is normally deiodinated and glucuroconjugated, →bile); signs of hyperthyroidism do not appear, because the hormone-fixing protein also increases → free thyroxine in the blood circulation is in the NV; - ↑ ADH Excess aldosterone and ADH = favors the appearance of edema and ascites. 8. Disturbance of hydro-electrolytic and acid-base balance Damage to the hepatocyte membrane → permeability changes with: - K+ exit from the cell →↑ its blood concentration, simultaneously with - the entry of Na+ and H+ into the cell, - elimination of K+ through the urine, with secondary hypokalemia and alkalosis. These phenomena are aggravated by: - hypovolemia → SRAA → Na+ retention in parallel with K+ loss; - insufficient degradation of hormones in the damaged liver, with secondary hyperaldosteronism → Na+ retention. !!! Na+ retention does not cause ↑ blood concentration, because it penetrates icellularly. In regard of phospho-calcium balance, disorders = hypocalcemia - ↓ serines that fix and transport ~ 40% of blood calcium, - insufficient calcium intake ← anorexia, - calcium absorption deficiency ←↓ secretion of HCl, pancreatic insufficiency and liver insufficiency, which disrupts the transfer of vitamin D3 into cholecalciferol. In hepatopathies → severe forms ↑ the volume of extracellular water through: - hyposerinemia, - secondary hyperaldosteronism and - ↑ ADH.  MORPHOLOGICAL MODELS OF HEPATIC INJURY The liver is an organ that, due to its structure, has a limited capacity to respond to various aggressions. Depending on the type of aggression, 5 types of reaction may occur: - focal necrosis - characteristics: microbial infections, in the chronic form of viral hepatitis. massive ← severe damage to the liver from toxins / drugs, ± viruses - degeneration – ballooned, edematous appearance of hepatocytes ← ← metabolic disorders of proteins, lipids, carbohydrates, hemoglobin pigments with/without iron, or the transport of water and electrolytes through the hepatocytic membrane - inflammation ← influx of inflammatory cells - regeneration ← thickening of proliferating hepatocyte cords → disorganization of parenchymal structures. !!! Even in massive hepatocellular necrosis, if the connective tissue network is intact, liver regeneration ~ restitutio ad integrum. If the pathological process affects the reticular network, the repair will require fibrous scarring → ± redistribution of blood circulation. - fibrosis ← inflammation / toxicity that acts directly on the liver - they deposit collagen, modify circulation and intrahepatic angina - as it expands, the liver divides into nodules of hepatocytic regeneration, surrounded by scar tissue = cirrhosis. metabolic disturbances lead to the accumulation of various substances in the liver, producing histopathological aspects of: - amyloidosis - hyalinosis - fibrinoid degeneration - glycogenosis - hepatic steatosis - hemosiderosis - biliary stasis  MORPHOPATHOLOGY OF DEGENERENCE (DYSTROPHY) OF THE HEPATIC Degenerative through disorders in protein metabolism The attraction of Na+ and water into the cell, with the simultaneous loss of K+. Ionic imbalance → cell swelling, especially mitochondria BM - intumescence can be: - turbid ← the active transport of ions through the hepatocytic membrane → ↑ temporary osmotic pressure; - appears in infections, intoxications, hypoxia, starvation; - vacuolar - often associated with the previous one - the mechanism is identical - especially in acute hypoxia, intoxications, hypokalemia; - vacuoles - devoid of content ← free cellular water; - hydropic - mechanism of hyperhydration of cells, swollen appearance; reversible / precursor to other types of dystrophies: Degenerative through disorders in the metabolism hemoglobin pigments These dystrophies are classified into two large groups: 1) dystrophies of pigments containing iron (hemosiderin), with accumulations - localized, or - generalized and 2) pigment dystrophies that do not contain iron (bilirubin). 1. Hemosiderosis located appear in ◼ foci of hemorrhages, ◼ stasis liver, ◼ hepatic hemangiomas; generalized ◼ are relatively rare ◼ they appear by overloading the body with iron or by the excessive accumulation of hemosiderin both in the liver and in the pancreas, kidneys, heart, lymph nodes, red marrow; - in most cases ← of hemolytic anemia and less often of iron treatment.  Hemochromatosis It represents a disorder in iron metabolism. It has a form: - primary or idiopathic and - secondary, in other diseases. Appears ← excessive absorption of iron = Bronzed diabetes ← accumulation of iron in tissues - liver cirrhosis, - diabetes mellitus, - skin pigmentation. The accumulation of iron in the liver has a cytotoxic effect, leading to: - degeneration and necrosis of hepatocytes; - fibrous scars and appearance of nodules (type of liver cirrhosis). Fig. Hereditary hemochromatosis. The deposition of iron in the cirrhotic liver is highlighted by the blue color of the Prussian blue 2. Pigment dystrophies that do not contain iron (bilirubin) Bile pigments in excess, regardless of the pathogenetic mechanism, it accumulates: In hepatocytes → foamy degeneration, Kupffer cells, where bile pigments are phagocytosed, bile canaliculi → - "bile plugs" Cholestasis. Bile canaliculi are dilated with thickened bile, and Kupffer cells contain phagocytosed bile (arrowhead). Hepatocytes appear with foamy degeneration and pigment accumulations (hematoxylin-eosin staining) In the absence of damage to the bile duct, hepatocellular cholestasis "per se" does not determine a definitive liver damage. BUT prolonged obstructive cholestasis → foamy changes of hepatocytes destruction of the parenchyma; coalescence of necrosis foci → "bile lakes", full of cellular debris and bile pigments. Biliary infarction (bile lake). Photomicrograph of the liver of a patient with extrahepatic biliary obstruction highlights an area of necrosis and the accumulation of extravasated bile Degenerations due to disturbances in lipid metabolism Hepatic steatosis has multiple causes (obesity, diabetes, alcoholism, various intoxications) It can be - limited to portions of the lobe, or - broadcast → deletion of the lobular pattern. MO liver cells are hypertrophied, lipid droplets appear in the cytoplasm → coalesce → unique → nucleus at the periphery.  Degenerative through disorders in the metabolism of carbohydrates Localized glycogenoses - DZ, where glycogen is in the cytoplasm and in the nucleus; less often in acute inflammations, anemias, leukemias. Generalized glycogenoses ← genetically determined enzyme deficiencies. Cori type I – associated with glucose -6-phosphatase deficiency → ↓ glucose-6-phosphate ↓ use glucose →​ hypoglycemia → ↑ liver glycogen + kidney → the hepatoepithelia and cells of the renal tubes will hypertrophy. Cori type II / Pompe disease associated with lysosomal acid alpha-glycosidase deficiency → now glycogen storage in lysosomes → they break the membrane and discharge the hydrolases into the cytoplasm of the cells. It also affects other organs: myocardium, skeletal muscles, nervous and lymphoid tissue, leukocytes ◼ organ hypertrophy, ◼ heart failure, ◼ mental disorders, ◼ skeletal muscle hypofunctionality. At the opposite pole of excess storage of glycogen in the cell, the reduction of glycogen content is evident → 0: ◼ inanity, ◼ hypoxia, ◼ hypovitaminosis, ◼ viral infections, ◼ cachexia cancer  Hyaline degeneration or hyalinosis Hyaline is a substance of - protein or glycoprotein nature, - acellular structure, - homogeneous, translucent and eosinophilic aspect. It is stored in tissues, predominantly extracellularly. In some viral liver infections or intoxications (chronic alcoholism), hyaline is deposited in the cytoplasm of liver cells in the form of eosinophilic droplets called Mallory hyaline bodies. Central hyaline sclerosis. The photomicrograph of a patient with alcoholic hepatopathy highlights the terminal central venule as being obstructed by fibrous tissue  Fibrinoid degeneration Fibrinoid is: ◼ acellular substance, ◼ acidophilus, ◼ homogeneous or finely granular and of ◼ complex structure. It has tinctorial affinity with fibrin, hence its name. Initially, swelling of the fundamental substance ← occurs GAG subsequently the process progresses, through the fragmentation and disintegration of collagen fibers, resulting in fibrinoid. Fibrinoid dystrophy affects the liver, especially in disseminated lupus erythematosus (systemic lupus erythematosus - SLE).  Amyloid degeneration Amyloid brings together a group of different proteins that: is stored extracellularly, they have certain common morpho-tinctorial characteristics and complex structure. In BM, amyloid appears as a hyaline type material, from which it differs by: ◼ tinctorial affinities, ◼ location, ◼ conditions of appearance. The structure of amyloid is fibrillar, with fibers: ◼ of different lengths, ◼ arranged in parallel, ◼ in the form of bundles with different orientations. The ultrastructural organization ~ of keratin, cellulose, collagen and elastin. Liver damage ← predominantly extracellular deposition - primary amyloidosis - rare cases, as well - secondary amyloidosis - more frequent and more severe cases.  MORPHOPATHOLOGY OF CHRONIC VIRAL HEPATITIS The morphological spectrum of chronic viral hepatitis (B or C): mild portal inflammation with reduced/absent cell necrosis → extensive processes of inflammation, necrosis and fibrosis. The common characteristics of chronic viral hepatitis are represented by: ◼ piecemeal necrosis, ◼ injuries in the port space, ◼ periportal fibrosis, ◼ lobular inflammation, ◼ necrosis and ◼ regeneration. The architecture of the lobule is initially preserved. If the collagenization process continues, disorganization and destruction of the liver is reached, with the evolution towards cirrhosis. Liver cirrhosis It has numerous causative agents. Histological spectrum - type: - micronodular - small, uniform nodules, separated by fine fibrous septa, generally in the initial stages of cirrhosis and - macronodular - nodules large in shape and size, visible with the naked eye, surrounded by bands of different widths of connective tissue. - mixed Laennec's micronodular cirrhosis - prototype alcoholic cirrhosis, CBP and secondary, hemochromatosis, Wilson's disease, Budd-Chiari syndrome and some hereditary disorders. - small nodules, less than 3 mm in diameter, uniform in size, shape and size, - the presence of Mallory bodies, - disorganization of the architecture of the entire liver parenchyma. Chronic hepatitis with cirrhosis. Photomicrograph of the liver of a patient with chronic active hepatitis type B highlights hepatocellular nodules and chronic fibrous septa. Macronodular cirrhosis - classically associated with chronic active hepatitis. - large nodules, ǿ=1 - 5 cm, uneven in size, shape / distribution; - the presence of the process of piecemeal necrosis in some nodules; - hepatic architecture - less compromised. The proliferation of regeneration nodules, the thickening of the septa and the distortion of the general architecture of the liver lead to the compression of the veins, with the appearance of portal hypertension. Micronodular type of cirrhosis ± → macronodular (the particular case of alcoholics)  Alcoholic hepatopathy Chronic alcoholism has various effects on the body, however the toxic one is at the level of the liver, where it determines: - hepatic steatosis, - alcoholic hepatitis, - alcoholic cirrhosis. The pathogenesis of fatty liver ????, the participation of different mechanisms varies depending on: - the amount of alcohol consumed, - the lipid content of the food diet, - fat accumulation in the body, - hormonal status and others. The main mechanisms involved in liver pathogenesis are: - excessive intake of fats in the liver cell and - altering their transport. The lipids accumulated in the hepatocyte come from 3 sources: - alimentary, predominant (in the form of chylomicrons and free fatty acids), - adipose tissue (through mobilization) and - intrahepatic (by synthesis). AG, regardless of the source, → in the liver following metabolic disturbances such as: - increasing their mobilization from adipose tissue, - decreasing LP release from the hepatocyte, - decreasing the intensity of the oxidative process of lipids in the liver, - intensification of hepatic lipogenesis of TG, fatty acids. Alcohol metabolism and its effects on liver cells Alcohol → inhibits the secretion of lipids in the Golgi apparatus → prevents the transport of triglycerides from the hepatocyte. → important caloric intake, but without proteins and vitamins → quickly to malnitritis. Prolonged ingestion of alcohol in large doses can cause serious liver damage even in the absence of any nutritional deficiency ; ± the association of a malabsorption syndrome, vit. (B1 and B12). !!! alcoholism and malnutrition potentiate their negative actions on the liver. Evolution towards cirrhosis in chronic and abusive alcohol consumption is favored by factors: - food, respectively - protein and vitamin deficiency, or - excess lipids →↑ toxicity of alcohol to the liver: while a normal diet does not represent a protective factor; - Microbes → modification of the immune response to certain microbial antigens, especially Escherichia coli; - genetics, with the predominance of histocompatibility HLA-B40 Antigen, → CNS tolerance to alcohol. Alteration of the immune response has an essential role in the pathogenesis of alcoholic liver disease Number of experimental studies → neither alcohol nor nutritional deficiencies alone can explain the accumulation of hyaline → inflammatory reaction that interferes with cytotoxic and chemotaxic reactions. Alcohol toxicity is responsible for: - hepatocytic necrosis, - granulocytic inflammatory infiltrate, as well as - the other manifestations of alcoholic hepatitis. Alcoholic hepatitis represents the inflammatory response of the liver to alcoholic aggression and the transformation path to cirrhosis of the alcoholic liver. The transition period from steatosis to cirrhosis lasts from 6 to 20 years. Hepatic steatosis it appears even with a moderate, but constant consumption of alcohol, in hepatocytes accumulating lipid droplets in the form of microvesicles and macrovesicles that compress and move the nucleus to the periphery of the cell. Electron microscopy highlights abnormalities of cellular organelles: - endoplasmic reticulum hypertrophy - mitochondrial lesions that appear from the early stages of steatosis; the lesions have a special significance because aldehyde dehydrogenase has a mitochondrial origin. In time, fibrosis also develops; until its appearance, the fatty change is completely reversible under the conditions of stopping alcohol consumption. Alcoholic hepatitis is a necrotizing lesion, characterized by: - necrosis hepatocytes - affects isolated cells or groups of cells; - hyaline inclusions - Mallory bodies are cytokeratin filaments coiled in the form of a ball, together with other proteins visible as eosinophilic inclusions in the cell cytoplasm; - inflammatory reaction - neutrophils accumulate around liver cells, - lymphocytes and macrophages also enter the portal spaces, spreading in the whole lobe; - fibrosis - almost always accompanies alcoholic hepatitis, being an active process at the sinusoidal and periportal level.  Alcoholic hepatitis A. Heaps of neutrophils mark the site of a necrotic hepatocyte. A Mallory body is present in a second hepatocyte (arrow). B. Mallory eosinophilic bodies are observed in hepatocytes, surrounded by fibrous tissue. (hematoxylin-eosin staining). Alcoholic cirrhosis it is installed in approximately 15% of alcoholics. Hepatocellular necrosis, fibrosis and regeneration evolve slowly and insidiously towards the formation of fibrous septa around the hepatocytic nodules, representing the two characteristics of fibrosis. The regeneration activity of trapped parenchymal acini generates micronodules very different in size. Over time the nodularity becomes more prominent. As the fibrous septa dissect and surround, the liver becomes fibrotic, with a macro- and micronodular appearance. Alcoholic cirrhosis. Nodules of different sizes are trapped in fibrous tissue. Fatty accumulations are also evident. (Masson trichrome staining) Granulomatous hepatopathy Macroscopically , the granulomatous liver can have a normal or increased volume, presenting on the surface and on section multiple nodules with a diameter between 0.6 and 2 mm. Nodules consist of: - epithelioid cells, derived from modified histiocytes and fibroblasts, - multinucleated giant cells resulting from the union of epithelioid cells, - fibroblastic proliferation surrounded by round cells of the type of lymphocytes and plasma cells, The giant cells are arranged centrally or peripherally, depending on the position of the nucleus and can be: - Langhans cells with nuclei located at the periphery and - foreign body cells with nuclei scattered in the cytoplasm Granulomas are associated with variable necrosis and mesenchymal proliferations. The liver consists of: ▪ hepatocytes ▪ Kupffer cells, other cell types ▪ vessels ▪ bile canaliculi structures that react specifically to different aggressions. Thus, liver viruses A, B, C, D, E, F, G attack hepatocytes, the rest of the structures responding to the destruction of liver cells, not directly to the virus. The infectious mononucleosis virus, a virus that also has hepatic tropism, causes attacks at the level of the reticulo-histiocytic system, not at the level of hepatocytes. Pancreatic head adenocarcinoma damages the bile canaliculi, as does liver cirrhosis. Each hepatic structure can be investigated by exploratory tests: A – metabolic or synthetic function of liver cells; B – liver cell damage; C – inflammation of the hepatic mesenchyme; D – excreto-biliary function; E – global investigation of the functional liver mass; F – viral markers; G – the presence of autoantibodies A. ​The liver plays a main role in protein, lipid, carbohydrate metabolism. Within protein metabolism, the factor participates in: synthesis and catabolism of serum proteins degradation of amino acids synthesis of urea, by: NH3 ← AA deamination (ureogenetic cycle) The exploration of the metabolic capacity of the liver reflects the number and quality of hepatocytes and is based on the dosage of factors synthesized exclusively / mainly liver: Albumine Serum cholinesterase Quick time Urea Fibrinogen In parenchymal insufficiency, ↓ the blood levels of these factors, ↑ NH3 ← ↓ ureogenesis in severe cases. In lipid metabolism, the liver participates in: synthesis of cholesterol, phospholipids, triglycerides → LP, VLDL and HDL; synthesis of bile acids; conjugation of bile acids with glycocol and taurine → bile salts → lipid emulsification → favors the action of pancreatic enzymes Thus, in the case hepato-cellular insufficiency - ↓ serum cholesterol level; of a mechanical obstruction (cholestasis) ↑ Chol + ↑↑ in serum of bile salts. Although the liver plays a particularly important role in carbohydrate metabolism, currently its exploration is minimal: the blood glucose level drops significantly only in severe liver damage, the overload tests (galactose test) were abandoned due to the lack of specificity (errors in the case of intestinal malabsorption). B. Liver cell damage can be of varying degrees, from changes in cell membrane permeability, to extensive cell necrosis, causing cellular suffering. As a result of cytolysis, the following are released into the blood: ◼ enzymes: GPT, GOT, OCT, GGT, LDH ◼ vitamin B12 (the liver is the storehouse) ◼ iron Cytolysis can be extensive, but not serious, as in acute hepatitis, expressed by increased values of substances released from hepatocytes; the process can in some cases be reversible, with the normalization of the values. There are also serious cases, without necrosis, with normal or slightly elevated enzyme values - liver cirrhosis. C. Evidence of mesenchymal inflammation. In infectious hepatitis (viral or parasitic), an inflammatory reaction occurs accompanied and maintained by an immune reaction, highlighted by: non-specific tests: Tymol, ZnSO4 specific tests: protein electrophoresis, protein immunoelectrophoresis, determination of IgG, IgM. In infectious hepatitis, a dysproteinemia is found through ↓ albumins ↑ gammaglobulins → proteins ~ NV In advanced forms of chronic hepatitis , in liver cirrhosis, the "β-γ" block is characteristic. !!! the Ritis Ratio: albumins / globulins, whose value becomes subunit in chronic hepatitis. d. Exploring the excreto-biliary function gives us information on bile secretion, by determining the concentrations: serums of: - bilirubin - total - direct - indirect - alkaline phosphatase - total, free cholesterol urination of: - UBG - bile pigments Corroboration of these data with those obtained through previous exploration samples, along with hematological examinations, helps in the differential diagnosis of the 3 types of hemolytic, mechanical, hepatogenic jaundice. Hemolytic jaundice Mechanical jaundice Blood - excess BI - can also appear in Blood hepatitis - Direct bilirubin - conjugation deficits - bile salts - Crigler-Najjar Sdr. - Gilbert Sdr. - cholesterol urine – UBG​ also by retention phenomenon duodenal juice – duodenal pigment in - Copper serum exces - α2 globuline chair – SBG - ALP liver exploration tests – negative, N - QT, correctable with parenteral stigmata of hemolysis vitamin K. - hemolytic anemia urine - pigments and bile salts - reticulocytes - Absence of UBG - disturbances: Hgb, enzymes duodenal juice - ↓ → 0 bile pigments - LDH in stool – SBG ↓ → 0 enterohepatic circuit in excess liver test samples – N - liver disease that appeared later ← bile stagnation NO enterohepatic circuit Hepatogenic jaundice Blood - ↑ BD, ↑ BI - ↑ bile salts - Total Chol – N /↓ (Esterified cholesterol ↓↓↓) urine – UBG varies - bilirubin and bile salts - "+" duodenal juice – bile pigments ↓ stool – SGB ↓ altered liver tests E. The global investigation of the functional liver mass, through liver transit tests, aims at: - the sinusoids - from the point of view of the vascularization of the liver; - hepatocytes - from the point of view of their ability to transport substances; - bile ducts - from the point of view of their permeability. The substances used in this type of exploration (BSP bromsulfonphthalein, indocyanine green, pink bengal) are injected intravenously, thus reaching the sinusoids, then the hepatocytes - which they actively pass through, enzymatically - finally being eliminated through the bile in the duodenum. By subsequently determining the concentrations of these substances after a certain time, we can find out if they have decreased to a certain percentage of the initial concentrations. Otherwise, it means that one of the three aforementioned sectors shows an alteration. F. Viral markers in viral hepatitis B Hepatitis B virus = Dane particle - outer shell = HBsAg - core - AgHBc capsid - DNA – polymerase - the viral genome Hepatitis B surface antigen (HBsAg) appears in the serum - long before the chronic disease - 2 weeks after infection persist 2 → 21 weeks (sickness period) presence = diagnosis Hepatitis type B more than 3 months from onset = chronicity / healthy carrier risk it is associated with the simultaneous presence of Dane particles or DNA polymerase. Anti-HBs or HBsAb (Hepatitis B surface antibody) appear in the serum after the serological window appear in convalescence if and only if the infection is self-limiting their appearance = healing + post-infectious immunity they are the only protective ones HBcAg is found only in liver cells, and can be highlighted by Immunofluorescence in the form of immune complexes (Ag – Ab) Anti-hepatitis B core (HBc) antibody = IgM = definite indicator of acute infection titer < = persistently active infection or exacerbations of a chronic process = proof of viral multiplication (active presence of hepatitis B virus) their absence = healing HBe Ag (hepatitis B e antigen) ← proteolysis of AgHBc appears in the blood early, along with: HBsAg and DNA polymerase activity transiently present in serum (1-2 weeks after onset) = index of viral replication persistent HBeAg = indication of evolution towards chronicity (active process) has negative predictive value increased infectivity – it is a marker of blood infectivity, which contains Dane particles HBe Antibody after the serological window they appear if and only if the evolution is favorable at least 4-8 weeks after the appearance of jaundice antiHBe and their persistence = favorable sign of healing (not absolute) Some consider only s angeles containing HBs Ag + HBe Ag to be infectious nucleocapsid 2 enzymes: DNA - polymerase - degree of action ~ Identic to viral replication reverse transcriptase !! Not all HBs Ag carriers are equally contagious !! Infectivity is maximum in people whose blood contains: ◼ particle Dane ◼ HBeAg ◼ and DNA polymerase ◼ are people with aggressive chronic hepatitis ◼ chronic hepatitis treated with immunosuppressants in the initial phase of the disease (difficult diagnosis) G. AutoAc Non-organ specific 1. ANA, 2. AMA, 3. ASMA 4. antimicrosomal 5. antialbumin 6. antiglobulin 7. antihepato-renal 8. hepatic soluble Ab Ag Organ specifics 1. liver antimembrane 2. anti ASGPR (antisialoglycoprotein receptor) 3. liver specific antilipoprotein 4. hepatocyte antimembrane HBsAg"-" does not exclude the presence of infection, one of the following situations being possible: 1. incubation period (HBsAg ”-“ 6 months after contagion); certification of HBV DNA infection – the most faithful; PCR 2. after disappearance = serological window period 3. HBs genomes can only be expressed, not secreted; d diagnosis by liver biopsy puncture 4. HBsAg secreted below the detection limit ("low-level carriers") 5. Circulating HBsAg blocked in immune complexes with antiHBs Ac: severe hepatitis; fulminant hepatitis (can reappear later / "unmasked" by corticosteroid therapy) 6. Mutant Hbs Ag, non-reactive with Ac from usual tests 7. In this case, only antiHBc – IgM put the diagnosis of active infection  Autoimmune manifestations of VH infection Serological Manifestations of skeletal ◼ Positive ANAs muscles ◼ Anticardiolipid antibodies ◼ Polyarthralgias ◼ Antithyroid antibodies ◼ Rheumatoid polyarthritis ◼ Anti-smooth muscle antibodies ◼ Systemic lupus erythematosus ◼ Rheumatoid factor Lymphoproliferative Glandular diseases manifestations ◼ Monoclonal gammopathy ◼ thyroid ◼ Low differentiation lymphoma ◼ Sialoadenitis Cryoglobulins involved ◼ Sjongren's syndrome ◼ Vasculitis ◼ Neuropathy  Antiphospholipid syndrome and platelet disorders Renal manifestations ◼ Proliferative membranous glomerulonephritis ◼ Membranous glomerulonephritis ◼ Acute proliferative glomerulonephritis  Autoimmune effects of IFN in patients with HCV Endocrine Dermatological ◼ Thyroid autoantibodies ◼ Alopecia ◼ Serious illness ◼ Vitiligo ◼ De novo insulin-dependent diabetes mellitus  Autoimmune manifestations of HCV infection Blood Lungs Hemolytic anemia De novo sarcoidosis Autoimmune thrombocytopenia Interstitial pneumonia Factor VIII inhibitors Neuromuscular Rheumatology Peripheral neuropathy Positive ANAs Myelopathy SLE type syndrome Vasculitis with autoimmune complexes Gastrointestinal and hepatic De novo biliary cirrhosis Kidneys De novo celiac disease Membranous glomerulonephritis Ischemic colitis Nephrotic syndrome