Copper metabolism disturbance
This appears in Wilson's disease (hepatocerebral degeneration, hepatolenticular degeneration). It is a hereditary disease in which liver ceruloplasmin production decreases. The responsible gene, which is located on chromosome 1, 3, is inherited in an autosomal-recessive fashion. The precise excretory defect and the mechanism of copper-induced cellular injury are unknown. Ceruloplasmin is alpha-2-globulin and can bind copper in the blood. As a result, copper becomes free from unstable bonds with plasma proteins and sediments in the tissue.
The clinical features are dominated by hepatic and neuropsychiatric manifestations as well as hemolytic anemia. Patients can present acutely, with fulminant hepatic failure, or, more commonly, with evidence of chronic hepatitis and cirrhosis. Kayser-Fleischer rings represent rings of copper deposited in Descemet's membrane of the cornea at the periphery of the iris (in the cornea it looks like green-brown ring on its margin of the cornea). They are found in all patients with central nervous system (CNS) involvement but are less frequent in patients without CNS effects. Occasionally, Kayser-Fleischer rings are seen in disorders associated with chronic cholestasis, such as primary biliary cirrhosis. Serum free copper, urine copper, and hepatic copper levels are all elevated, whereas the total serum copper and serum ceruloplasmin levels nearly always are decreased.
Copper accumulates in the liver, brain, kidneys, pancreas, testes, etc. The state is characterized by development of liver cirrhosis, degenerative symmetrical changes in the brain in the area of lens nuclei, caudal body, pale globe, cortex. There are 3 forms of the disease: hepatic, lenticular, hepatolenticular.
The outcome is unfavorable.
Potassium metabolism disturbances
Increased blood (hyperpotassemia) and tissue potassium amount is observed in Addison's disease and is associated with the lesion of the adrenal cortex, the hormones of which regulate electrolyte exchange.
Potassium deficiency characterizes periodic paralysis, hereditary disease for which attack of weakness and motor paralysis are typical.
Iron metabolism disturbances are observed in disorders of hemoglobinogenic pigments metabolism. (See Pathology of Pigments).
Stones, or calculi are dense formations freely lying in the cavities of the organs or in the ducts.
Their shape depends on the organs in which they are formed: round in the urinary bladder, facet in the gallbladder (their faces are lapped to each other), branching in the kidneys. Their surface may be either
smooth or rough. The color depends on their chemical composition: white (phosphates), yellow (urates), dark brown or green (pigment). On saw cut they may be crystalloid (radial structure), colloid (stratified structure) and colloid-crystalloid (radial-stratified). Their chemical composition is different, i.e. biliary calculi may be cholesterol, pigment, calcium and combined, urinary — urates, phosphates, oxalates (calcium oxalate), cystin, xantin. Bronchial calculi consist of mucus inlayed with calcium. Calculi are most frequently formed in the bile ducts and urinary tract in cholelythiasis, urolythiasis, in the excretory ducts of the pancreas, salivary glands, bronchi, crypts of the tonsils, veins (phlebolith), intestine (coprolith).
Both general and local factors are important for pathogenesis of calculus formation. General factors are the main ones, they are acquired or hereditary disturbances of metabolism. Local factors are secrete congestion, inflammation of an organ. The immediate mechanism of calculus formation consists of two processes: formation of organic matrix and salt crystallization. Each of these may be primary.
Compression with a stone may result in necroses in renal pelvis, gallbladder etc., bedsores, perforations, inflammation (pyelocystitis, cholecystitis, cholangitis etc.).
Stages of individual work in class Study and describe the macrospecimens
Calcified fibromyoma of the uterus. Describe the shape, size, texture and colour of the calcified area under section. State the possible changes in the tumour, which caused deposition of calcium salts. What mechanism caused this type of calcinosis?
Femur in parathyroid osteodystrophy. Describe the states of the soft and compact core (part) of the bone. What changes occur in the bone tissue? What mechanism caused this type of calcinosis and what are the possible organs where we can find deposition of calcium salts.
Gallstones. Determine the size of the gallbladder. What has filled its cavity? Describe the colour of the stones, the size and the surface. Name the stones of the bile duct according to their chemical composition.
Renal calculi (stones). The appearance of the stones, their shape and surface. Pay attention to the changes in renal tissues. What is the possible outcome of renal stones?
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