Pathophysiology. Asst. Prof. Dr. Dalya Basil. Disorders of GIT and Hepatobiliary System

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1 Pathophysiology Lecture 15 Asst. Prof. Dr. Dalya Basil Disorders of GIT and Hepatobiliary System Viral Hepatitis: is a liver inflammation caused by five unrelated hepatotropic viruses Hepatitis A, Hepatitis B, Hepatitis C, Hepatitis D, and Hepatitis E. Other viruses can also cause liver inflammation include Herpes simplex, Cytomegalovirus, Epstein Barr virus. It may present in acute (recent infection, relatively rapid onset) or chronic forms. Hepatitis A Hepatitis B Transmitted through contact with blood or fluid of the infected person.

2 Health workers are very exposed to this disease, especially when using infected needle and syringes. It may be transmitted from mother to child (maternal). Symptoms of Hepatitis B Viral Infection : - Loss of appetite - Yellowing of skin and eyes (jaundice) - Nausea and vomiting - Fever - Weakness - Abdominal pain - Joint pain - Dark urine - Clay-colored stool Hepatitis C HCV can be transmitted through contact with blood, and can also cross the placenta. Hepatitis C usually leads to chronic hepatitis, with cirrhosis in some people. It usually remains asymptomatic for decades. Clinical manifestations of HCV: 70-80% of people with hepatitis C don t show any symptoms. But in the other people the clinical manifestations may include: - Yellowing skin and eyes - Dark urine

3 - Light-colored stool - Nausea and vomiting - Loss of appetite - Extreme fatigue Hepatitis D and Hepatitis E The Hepatitis D virus (HDV) or hepatitis delta agent is similar to a viroid as it can only propagate in the presence of the hepatitis B virus. Transmitted parenterally. The Hepatitis E virus (HEV), produces symptoms similar to hepatitis A, although it can take a fulminant course in some patients, particularly pregnant women; chronic infections may occur in immune-compromised patients. Transmitted by fecal-oral route. Primary Biliary Cirrhosis Is a chronic disease of the liver characterized by the autoimmune destruction of the medium-sized intrahepatic bile ducts with cholestasis and eventual development of cirrhosis and liver failure. The disease is seen most commonly in women 40 to 60 years of age. Genetic and environmental factors are important in its pathogenesis. Manifestations of Primary Biliary Cirrhosis The disorder is characterized by an extremely insidious onset, and persons may be symptoms free for many years. Morphologically, there is progressive scarring and destruction of liver tissue.

4 The liver becomes enlarged and takes on a green hue because of the accumulated bile. The earliest symptoms are unexplained pruritus or itching, weight loss, and fatigue, followed by dark urine and pale stools. Vitamin D malabsorption-related osteoporosis occurs in up to one third of persons with the disorder. Jaundice is a late manifestation of the disorder, as are other signs of liver failure. Serum alkaline phosphatase levels are elevated in persons with primary biliary cirrhosis. Liver Failure The most sever clinical consequences of liver disease is hepatic failure. Liver failure occurs when large parts of the liver become damaged and the liver is no longer able to function. Liver failure is a life-threatening condition that demands urgent medical care. Most often, liver failure occurs gradually and over many years. However, a more rare condition known as acute liver failure occurs rapidly (in as little as 48 hours) and can be difficult to detect initially. Causes of Liver Failure Liver failure may result from sudden and massive liver destruction, as in fulminant hepatitis, or be the result progressive damage to the liver, as occurs in alcoholic cirrhosis. With no relation to the cause, 80%-90% of hepatic functional capacity must be lost before hepatic failure occurs. Manifestations of Liver Failure

5 - Anemia: may be caused by blood loss, excessive red blood cell destruction, and impaired formation of red blood cells. A folic acid deficiency may lead to sever megaloblastic anemia. - Thrombocytopenia: often occurs as the result of spleenomegaly. - Leukopenia - Hepatorenal syndrome that refers to a functional renal failure and sometimes seen during the terminal stages of liver failure with ascites. It characterized by progressive azotemia, increased serum creatinine levels, and oliguria. - If the renal failure is accompanied by liver failure, azotemia occur, this condition is thought to contribute to hepatic encephalopathy. - Hepatic encephalopathy characterized by neural disturbances ranging from a lack of mental alertness to confusion, coma, and convulsions. The accumulation of neurotoxins, which appear in the blood because the liver has lost its detoxifying capacity, may cause the hepatic encephalopathy.