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Main Clinical Syndromes. Jaundice is an icteric colouration of the skin and mucosa by the increas­ed content of bilirubin in the tissues and blood






Jaundice

Jaundice is an icteric colouration of the skin and mucosa by the increas­ed content of bilirubin in the tissues and blood. The serum of blood taken from patients with true jaundice also becomes intense yellow. Jaundice is attended (often preceded) by changes in the colour of the urine, which becomes dark-yellow or brown; faeces can be very light or even colourless, or on the contrary, dark-brown.

Jaundice can develop very quickly, within 1-2 days, to become very in­tensive, or it can develop gradually and be not pronounced (subicteric). Pa-


tients themselves (or their relatives) notice yellow colour in their skin. They consult a doctor for this reason. Jaundice can develop with severe itching of the skin, skin haemorrhages and haemorrhages of the nose and the gastro-intestinal tract.

Jaundice occurs in many diseases of the liver, bile ducts, blood, and also diseases of other organs and systems, to which bilirubin metabolic disorders are secondary. Some clinical symptoms attending jaundice are to a certain degree suggestive of its type and origin. Accurate diagnosis of various types of jaundice is possible with special laboratory studies.

True jaundice can develop due to the following three main causes: (1) excessive decomposition of erythrocytes and increased secretion of bilirubin (haemolytic jaundice); (2) impaired capture of unbound bilirubin by the liver cells and its inadequate combination with glucuronic acid (parenchymatous jaundice); (3) obstacles to excretion of bilirubin with bile into the intestine and reabsorption of bound bilirubin in the blood (obstructive jaundice).

Haemolytic (haematogenous) jaundice develops as a result of excessive destruction of erythrocytes in the cells of the reticulohistiocytic system (spleen, liver, bone marrow). The amount of unbound bilirubin formed from haemoglobin is so great that it exceeds the excretory liver capacity to account for its accumulation in the blood and development of jaundice. Haemolytic jaundice is the main symptom of haemolytic anaemia. It can also be a symptom of other diseases, such as B12-(folic)-deficiency anaemia, malaria, protracted septic endocarditis, and other diseases.

The skin of a patient with haemolytic jaundice is lemon-yellow. Skin itch­ing is absent. The amount of unbound bilirubin in the blood is moderately in­creased (50—200 per cent); the van den Bergh test for bilirubin is in­direct. Bilirubin is absent from the urine but the urine is still coloured rather intensely by the markedly increased (5-10 times) stercobilinogen and (partly) urobilinogen. Faeces are intense dark due to the presence of considerable amount of stercobilinogen.

Parenchymatous (hepatocellular) jaundice develops due to the damage of the parenchyma cells (hepatocytes). These cells can capture bilirubin of the blood and bind it with glucuronic acid (the natural detoxicating func­tion of the liver). The natural process of bilirubin excretion in the bile in the form of bilirubin glucuronide (bound bilirubin) is thus impaired. The content of free and bound bilirubin in the blood serum thus increases 4—10 times. In rare cases the increase may be even greater: free bilirubin in­creases due to hepatocyte dysfunction and bound bilirubin content in­creases as a result of back diffusion of bilirubin glucuronide from biliary into blood capillaires in dystrophy of the liver cells. Bound bilirubin ap­pears in the urine (bilirubin glucuronide is water soluble and easily passes



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via the capillary membranes as distinct from free bilirubin). Bile acids are also present in urine, but their content gradually increases. Excretion of stercobilinogen with faeces also decreases because the amount of bilirubin excreted by the liver into the intestine decreases, but faeces are rarely com­pletely discoloured.

This type of jaundice is mainly determined by infection (virus hepatitis or Botkin's disease, leptospirosis) and toxic affections of the liver (poison­ing with mushrooms, phosphorus, arsenic and other chemical substances, medicinal preparations included). But parenchymatous jaundice can develop also in liver cirrhosis.

The skin of patients with this jaundice is typically yellow with a reddish tint. Skin itching is less frequent than in obstructive jaundice because the synthesis of bile acids by the affected liver cells is upset. Symptoms of pro­nounced hepatic insufficiency may develop in severe course of the disease.

There exists a group of congenital pigmentary hepatoses in which the liver is not affected pathologically, the functional tests are negative, while the process of bilirubin conjugation with glucuronic acid is upset at some of these stages (Gilbert syndrome). This condition is attended by a perma­nent or intermittent jaundice, which is sometimes pronounced and develops from infancy.

Obstructive (mechanical) jaundice develops due to partial or complete obstruction of the common bile duct. This occurs mostly due to compres­sion of the duct from the outside, by a growing tumour (usually cancer of the head of the pancreas, cancer of the major duodenal papilla, etc.), or due to obstruction by a stone. Bile congestion above the point of obstruc­tion develops and this elevates pressure inside bile passages in continuing bile excretion. As a result, the interlobular bile capillaries become distend­ed and bile diffuses into the liver cells (where dystrophic processes develop) and passes into the lymph and the blood. Moreover, due to increased pressure inside fine bile capillaries, communications are formed at the periphery of the lobules between the capillaries and the lymph spaces, through which bile enters the blood vessels.

Skin and mucosa of patients with obstructive jaundice are yellow. Later, as bilirubin is oxidized to biliverdin, the skin and mucosa turn green and dark-olive. The bound bilirubin content in the blood with direct van der Bergh test is as high as 250-340 mmol/1 or 15-20 mg/100 ml, and more. In protracted jaundice associated with liver dysfunction, free bilirubin content increases as well. Bound bilirubin can be found in the urine (the presence of bile pigments is determined by urinalysis) to give it brown colour and bright-yellow foaming. Faeces are colourless either periodically (in incomplete obstruction, usually by a stone), or for lengthy periods of time (in compression of the bile duct by a tumour). Jaundice in-


I


creases progressively in such cases; the skin and mucosa gradually turn greenish-brown; cachexia of the patient increases. In complete obstruction of the bile ducts, faeces become colourless (acholic); their colour is clayish and grey-white; stercobilin is absent from faeces.

Bound bilirubin and also bile acids produced by the hepatocytes in am­ple quantity (cholaemia) are delivered to the blood in this type of jaundice. Some symptoms associated with toxicosis develop: pronounced skin itching, which intensifies by night, and bradycardia (bile acids increase the tone of the vagus nerve by reflex). The nervous system is also affected: the patient develops rapid fatigue, general weakness, adynamia, irritability, headache, and insomnia. If it is impossible to remove the cause of impaten-cy of the common bile duct (stones or a tumour) the liver is gradually af­fected to add symptoms of hepatic insufficiency.

Portal Hypertension

Portal hypertension is characterized by a stable increase in the blood pressure in the portal vein. Portocaval anastomoses are dilated, ascites develops and the spleen increases in size.

Portal hypertension develops due to obstructed blood outflow from the portal vein as a result of its compression from the outside (by a tumour, enlarged lymph nodes of the porta hepatis in cancer metastases, etc.), or by obliteration of part of its intrahepatic branching in chronic affections of the liver parenchyma (in cirrhosis), or due to thrombosis of the portal vein or its branches. Growth and subsequent cicatrization of connective tissue at the site of degraded hepatic cells of a cirrhotic liver cause stenosis or complete obliteration of part of hepatic sinusoids and intrahepatic vessels. An obstacle is thus created to the blood flow which increases portal pressure and interferes with blood outflow from the abdominal viscera. In these conditions, transudation of fluids from the vessels into the ab­dominal cavity is intensified to account for the development of ascites. Decreased oncotic pressure of plasma is an important factor in the develop­ment of ascites associated with liver cirrhosis. The pressure decreases because of upset synthesis of albumins in the liver. Sodium and water retention is also important. It occurs due to hypersecretion of aldosterone by the adrenal glands (secondary aldosteronism) and its inadequate inac-tivation in the liver. The time of the onset of ascites depends on the degree of development of collateral circulation, i.e. on portocaval anastomoses. For a long time the disturbed portal circulation can be compensated for by delivery of blood into the superior and inferior venae cavae from the portal vein via normally existing anastomoses. But in portal hypertension these anastomoses become highly developed.


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There exist three groups of natural portocaval anastomoses: (1) in the zone of haemorrhoidal venous plexus; these are anastomoses between the inferior mesenteric vein (the portal vein system) and haemorrhoidal veins emptying into the inferior vena cava; haemorrhoidal nodes develop in por­tal hypertension which rupture to cause rectal haemorrhage; (2) anastomoses in the zone of the oesophagogastric plexus: this is a collateral leading through the left gastric vein, the oesophageal plexus, and hemiazygos vein into the superior vena cava. In pronounced portal hypertension, marked varicose nodes are formed in the lower portion of oesophagus whose injury (e.g. by hard food) is responsible for possible haemorrhage in the form of haematemesis (blood vomiting), which is the most serious complication of diseases attended by portal hypertension and which is a frequent cause of death; (3) anastomoses in the system of paraumbilical veins communicating with the veins of the abdominal wall and the diaphragm, carrying blood to the superior and inferior venae cavae. In portal hypertension, varicose veins radiate from the umbilicus to give a peculiar pattern known as the caput medusae.

The degree of increase in the pressure in the portal vein system can be determined by a special needle and a water pressure gauge. The pressure is measured in the spleen (splenometry) or in varicose veins of the oesophagus. In the latter case the needle is introduced through the oesophagoscope. It is believed that pressure in the spleen is the same as in the portal vein trunk. Normally it is 70—150 mm H2O, while in portal hypertension it rises to 400—600 mm H2O. Contrast techniques are used to reveal obstruction of the portal vein: these are splenoportography and in rare cases transumbilical portohepatography.

The spleen may be somewhat enlarged in venous congestion associated with portal hypertension.

Treatment. In order to remove portal hypertension, whose first danger are oesophagogastric and haemorrhoidal haemorrhages, the patients are operated on for placing anastomoses between the portal vein system and the inferior vena cava.

Hepatolienal Syndrome

The hepatolienal syndrome is characterized by concurrent enlargement of the liver and the spleen in primary affection of either of these organs. In­volvement of both organs in a pathological process (diseases of the liver, blood, certain infections, poisoning) is explained by their richly developed reticulohistiocytic tissue. In certain cases, e.g. in thrombosis of the hepatic veins, simultaneous enlargement of the liver and the spleen is determined


by venous congestion in them. In addition to palpation, scanning can be used to reveal the hepatolienal syndrome.

Considerable enlargement of the spleen is usually attended by its hyper-function (hypersplenism), which is characterized by anaemia, leucopenia, and thrombocytopenia. The latter can cause haemorrhagic complications. These changes are explained by inhibition of the haemopoiesis in the bone marrow due to hyperactivity of the spleen as a result of which destruction of the blood cells in the spleen is intensified, and antierythrocytic, an-tileucocytic, and antithrombocytic auto-antibodies are formed in the spleen.

Hepatic Insufficiency and Coma

Despite the considerable compensatory capacity of the liver, its grave acute and chronic diseases are attended by deep disorders in its numerous and very important functions due to the marked dystrophy and destruction of the hepatocytes. Clinicists define this condition as the hepatic insuffi­ciency syndrome.

Depending on the character and acuity of the affection acute and chronic hepatic insufficiency are distinguished. The following three stages of the disease are also distinguished: (1) early compensated stage; (2) pro­nounced decompensated; and (3) terminal dystrophic stage that ends in a hepatic coma and death.

Acute hepatic insufficiency arises in grave forms of virus hepatitis (Botkin's disease) and poisoning with hepatotropic substances (affecting the liver in the first instance). These may be chemical substances (e.g. phosphorus compounds, arsenic, large doses of alcohol) or vegetable poisons (inedible mushrooms containing amanitotoxin, helvellic acid, or muscarine extracted of male fern, etc.). Acute hepatic insufficiency develops rapidly, within several days or hours.

Chronic hepatic insufficiency develops in many chronic diseases of the liver, e.g. in cirrhosis and tumours. Its development is slow and gradual.

Development of hepatic insufficiency is underlain by marked dystrophy and necrobiosis of hepatocytes which is attended by a considerable impair­ment of all liver functions with formation of collaterals between the portal vein system and the venae cavae. Collaterals develop in cases when the blood flow from the portal vein into the liver is obstructed in any affection of this organ. Large amounts of blood containing toxic substances absor-bable in the large intestine pass through the collaterals into the greater cir­culation system to bypass the liver. Hepatic insufficiency is explained by various complicated metabolic disorders in the liver, upset bile secretory and excretory function, and impaired detoxicating function of the liver.

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The pathogenesis of hepatic coma is manifested by grave self-poisoning of the body due to almost complete dysfunction of the liver. The body is poisoned by the non-detoxicated products of intestinal (bacterial) protein decomposition, final products of metabolism, and especially ammonia. Normally, the major part of ammonia is captured by the hepatocytes and converted to urea (in the ornithine Kreb's cycle), which is then excreted by the kidneys. Phenols, which are normally detoxicated in the liver by their combination with glucuronic and sulphuric acids, also have a toxic effect. Other toxic substances also accumulate in the blood in the presence of hepatic insufficiency. The electrolyte metabolism becomes upset, and in severe cases, hypokaliaemia and alkalosis develop.

Hepatic insufficiency may be aggravated and coma may be provoked by alcohol, barbiturates, some analgesics (morphine, promedol), protein-rich diet (which intensifies putrefactive processes in the intestine, produc­tion of toxic substances and their absorption in the blood), by profuse haemorrhage from the digestive tract (which often aggravates portal cir­rhosis of the liver), by large doses of diuretics, instantaneous withdrawal of large amounts of ascitic fluid, severe diarrhoea, and the attending grave in­fectious diseases.

Clinical signs of hepatic insufficiency usually combine with symptoms of the liver disease that provoked hepatic insufficiency.

The intensification of the symptoms by stages is vividly illustrated by the progressive development of hepatic insufficiency (in patients with liver cirrhosis, tumour of the liver, and other diseases of this organ).

The clinical symptoms are absent during the early stage of hepatic in­sufficiency, but the body's tolerance to alcohol and also to other toxic substances decreases, and the findings of laboratory load tests change.

During the second stage, clinical signs of hepatic insufficiency develop; first mild but later more pronounced non-motivated fatigue, poor appetite, increased weakness in usual physical exertion, frequent dyspepsia (poor tolerance of fat food, the presence of meteorism, rumbling and pain in the abdomen, changed stools), which are explained by disorders of bile secre­tion and digestive processes in the intestine. Upset assimilation of vitamins explains polyhypovitaminosis. Fever, which is not infrequent in hepatic in­sufficiency, can be due to both the main disease and impaired detoxication of some proteinous pyrogens by the liver. Jaundice and hyper-bilirubinaemia with accumulation of free (indirect) bilirubin in the blood are frequent in hepatic insufficiency. Deranged structure of the liver and upset cholestasis can stimulate accumulation of bilirubin glucuronide (" direct" bilirubin) in the patient's blood.

Deranged albumin synthesis in the liver and also pronounced hypoalbuminaemia can cause hypoproteinaemic oedema and intensify


ascites, which often occurs in patients with chronic liver affections. Upset synthesis of some blood coagulating factors (fibrinogen, prothrombin, proconvertin) and also decreased blood platelet content (due to hypersplenism that attends many chronic diseases of the liver) provoke the onset of haemorrhagic diathesis (skin haemorrhages, nasal bleeding, haemorrhage in the intestinal tract). Inadequate inactivation of oestrogens by the chronically affected liver provokes endocrine disorders (gynaecomastia in men, menstrual disorders in women, etc.).

Changes in laboratory tests (hepatic tests) are significant in the second stage of hepatic insufficiency. Characteristic is the decreased content of substances produced by the liver: albumin, cholesterol, fibrinogen, etc. Considerable changes in the liver function are also revealed by radioisotope hepatography.

The third, final stage of hepatic insufficiency is characterized by even deeper metabolic disorders and dystrophic changes, which are pronounced not only in the liver but also in other organs. Patients with chronic liver diseases develop cachexia. They also suffer from nervous and psychic disorders which are precursors of coma: decreased mental ability, slow thinking, slight euphoria, sometimes depression, and apathy. The patient becomes easily irritable, his moods are quickly changed, attacks of melan­choly and frustration occur at times, and sleep is deranged. Derangement of consciousness and loss of orientation in time and space develop along with partial loss of memory, disordered speech, hallucinations, and som­nolence. Specific tremor (slow and fast) of the upper and lower limbs is characteristic.

The precoma period may last from a few hours to several days and even weeks. The patient may recover from this state, but coma develops in most cases.

The clinical picture is characterized first by excitation and then by general inhibition (stupor) and progressive derangement of consciousness (sopor), to its complete loss (coma). The EEG curve is flattened. The reflexes are decreased, but hyper-reflexia and pathological reflexes (suck­ing and grasping) develop. Motor anxiety, clonic convulsions due to hypokaliaemia, muscular twithching, and tremor of the extremities (ar­rhythmical and rhythmical twitching of the fingers and toes) are characteristic. Respiration rhythm becomes upset. Kussmaul respiration (less frequently Cheyne-Stokes respiration) develops. Incontinence of faeces and urine ensues. The patient's breath (and also urine and sweat) smells " sweety hepatic" (fetor hepaticus) because of liberation of methyl mercaptan which is formed in deranged methionine metabolism. Inspec­tion of the patient often reveals signs of haemorrhagic diathesis (bleeding gums, nasal and skin haemorrhage). The patient's temperature in the ter-



Special Part


Chapter 7. Digestive System



 


'jj minal period is subnormal. Jaundice is intensified. The liver may remain

enlarged or its size may decrease. Laboratory tests show moderate
anaemia, leucocytosis, increased ESR, low counts of platelets and
v fibrinogen; the prothrombin time increases, hepatic functional tests

" * become sharply upset, and the bilirubin level increases. The content of

i j residual nitrogen and ammonia in the blood serum increases to indicate

I * secondary affections of the kidneys (the hepatorenal syndrome).

j Hyponatriaemia, hypokaliaemia, and metabolic acidosis develop. Hepatic

> ' coma usually terminates fatally. But the patient can in some cases be saved.

Treatment. Intensive therapy is required in acute hepatic insufficiency: infusion of plasma, polyglucin, glutamic acid solution (to bind ammonia), oxygen, correction of water-salt disorders; the life of the patient should be maintained during the critical period (several days) to help the strong regenerative capacity of the liver. In addition to the treatment of the main disease, chronic liver diseases should be treated by removing the ag­gravating factors (oesophagogastric haemorrhage, attending infections). The diet should be poor in protein in order to suppress the putrefactive processes in the intestine; antibiotics decrease absorption of decomposed proteins. The electrolyte disorders are corrected and haemorrhages are controlled.

Recently methods for transplantation of healthy liver to patients with hepatic insufficiency are being developed.






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