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Diseases of bodies of an urinary system at children

Table of contents
Diseases of bodies of an urinary system at children
Physiology of kidneys
Diagnostic assessment of structure and function of kidneys
Diagnostic assessment of structure and function of kidneys - a proteinuria
Diagnostic assessment of structure and function of kidneys - a hamaturia
Ability of kidneys to concentrate urine
Excretion of amino acids, electrolytes and other metabolites from kidneys
Clearance and reabsorption of kidneys
Diagnostic methods of research of urinary tract
Diseases of kidneys with involvement in process of balls
Nephrotic syndrome
Nephrotic syndrome with the minimum changes
Nephrotic syndrome with a focal glomerulosclerosis
Hymenoid glomerulonephritis
Hymenoid and proliferative glomerulonephritis
Nephrotic syndrome at children of the first year of life
Other diseases which can be followed by a nephrotic syndrome
Acute glomerulonephritis
High-quality resistant proteinuria
Glomerulonephritis and septicaemia at infection of shunts
Nephrite at a system lupus erythematosus
Hemorrhagic vasculitis
Gemolitiko-uremichesky syndrome
Proliferative ekstrakapillyarny glomerulonephritis
Changes of function of tubules of kidneys
Fankoni's syndrome, nephrogenic not diabetes mellitus
Renal glycosuria
Cystinuria
Hereditary and family diseases of kidneys
Alport's syndrome
High-quality family hamaturia, nefronoftiz
Hereditary onikhoosteoplaziya, lipodystrophy
Family nephrotic syndrome, sickemia and kidneys, oxarods
Acute renal failure
Chronic renal failure
Infections of uric ways
Tuberculosis of uric ways, acute hemorrhagic cystitis
Anomalies of development of kidneys and collective system
Accessory, fused kidney, dysplasia and ectopia of kidneys
Bilateral increase in the sizes of kidneys at newborns, doubling of kidneys, the alternating hydronephrosis, inborn anomalies
Urolithiasis
Vascular diseases of kidneys
Thrombosis of renal veins at children of the first year of life
Renovascular hypertensia and diseases of renal arteries
Enuresis
Toxic nephropathy
Intersticial nephrite
Obstructive uropathy
Myoglobinuria and rabdomioliz
Diabetic nephropathy
Anomalies of development of collective system of kidneys
Anomalies of development of a bladder and urethra
Anomalies of development of outside man's generative organs
Anomalies of development of testicles
Infections of uric ways
Inflammatory processes in kidneys and pararenal fabric
Prostatitis, epididymite
Inflammation of external genitals
Disturbances of an urination
Injury of urinogenital system

Pediatrics.  Diseases of bodies of an urinary system. / Under the editorship of R. E. Berman, V. K. Vogan: The lane with English — M.: Medicine, 1988. In the book questions of urology of children's age are taken up. Anatomo-physiological features, inspection methods, clinic, diagnosis, the principles of treatment and prevention of diseases are in detail stated.
For pediatricians of all profiles.

 

URINARY SYSTEM
kidneys

  1. ANATOMY OF KIDNEYS

Kidneys, ureters and bladder are located in retroperitoneal space. Kidneys are at the I—IV level of lumbar vertebrae at the level of a navel or are slightly higher; at newborns they are usually palpated. Each kidney consists of 8 — 12 shares of a pyramidal form. Its external surface at a fruit is divided into segments, in process of growth lobation disappears. The basis of each share creates a surface, the nipple turned into a small renal cup is formed of top. Each share consists of two main zones: cortical, or external in which balls, proximal and distal gyrose tubules, and brain, or internal in which there are direct tubules, the descending and ascending parts of a nephronic loop and collective channels are localized. These structural units are located fanlikely, forming a funnel towards a nipple where urine comes through collective tubules to a small renal cup. Small cups open in upper and lower big from which urine comes to a renal pelvis, and then on an ureter as a result of its active reductions in a bladder.
Blood supply. The kidney receives about 10% of blood after each cordial emission and in relation to body weight represents body through which the most large number it proceeds.
From a ventral aorta blood comes to a kidney on renal, or main, arteries; sometimes them a little. As the main branches serve the interlobar arteries passing dorsalno and ventrally between shares to a renal pelvis. They are divided into arc arteries in the area between brain and cortical zones, passing parallel to a kidney surface. Interlobular arteries (fig. 13-1) depart from them perpendicular to a surface in cortical part. The last give rise to afferent arterioles, each of which supplies the ball representing a spherical network of the capillary loops surrounded with a capsule. Other interlobular artery passes directly to a bark surface, delivering to it a large amount of blood.
кровоснабжение  почки
Fig. 13-1. Schematic image of blood supply of a kidney
Approximately at distance of 50 microns to an entrance to a ball on average a layer of an afferent arteriole there are secretory cells containing a renin. They make the juxtaglomerular device. An arteriole, entering a ball capsule, is divided into several branches, the capillaries in turn forming a network around it. Gathering, these branches form efferent arterioles at which breaks up to the capillaries braiding tubules of the same nephron again. The number of epithelial canal cells decreases; this part of tubules is called by macula densa.
Blood supply of nephrons of bark is other than that the yukstamedullyarny nephrons located in a junction of cortical and brain zones (fig. 13-2). Diameter of efferent arterioles is slightly more than diameter afferent whereas in cortical nephron a ratio the return. Efferent arterioles externally - and intra cortical nephrons break up, forming the network surrounding proximal and distal parts of gyrose tubules, cortical part of a loop of a ball and a collective channel. For subcapsular, or vneshnekortikalny, nephrons these pericanalicular capillaries are formed of an efferent arteriole of a ball; at the nephrons located in deeper part of bark, the pericanalicular capillary network is freely connected with efferent arterioles of other nephrons. Walls of pericanalicular capillaries much thinner and connect to the basal membrane surrounding each tubule. Cortical capillaries eventually connect in interlobular veins.

Кровоснабжение нефронов коркового и юкстамедуллярного слоев
Fig. 13-2. Blood supply of nephrons of cortical and yukstamedullyarny layers

Efferent arterioles of internal cortical and yukstamedullyarny nephrons form a capillary network around proximal and distal gyrose tubules, loops of a ball and collective channels of this zone. Blood from efferent arterioles of yukstamedullyarny nephrons comes to the direct vessels representing the returnable arterial loops passing parallel to loops of balls and go down through a brain zone to nipples. Direct vessels go to bends of loops in yukstamedullyarny area up and enter an interlobular or arc vein. Direct vessels participate in the counterflow mechanism of concentration of urine (see further).
The general scheme of a venous drainage corresponds that arterial. The cortical part normal receives about 75% of the blood proceeding through kidneys (400 mg / 100 of cortical substance in min.); about 20% of blood come to yukstamedullyarny part of bark, and other — to an external brain zone. Through an internal brain zone blood flows more slowly, promoting maintenance of higher concentration of salts that is essential important to urine concoction. Physiological or pathological factors change distribution of a blood-groove in kidneys. For example, salt loading or reception of diuretic (for example, furosemide) promotes increase in a blood-groove and glomerular filtering in nephrons of a vneshnekortikalny layer. At heart failure, shock or dehydration perfusion happens generally in internal cortical and yukstamedullyarny areas. Possibly, in this complex of regulatory functions the significant role belongs to an autonomous nervous system, humoral factors, it as antidiuretic hormone, angiotensin and prostaglandins.

Nephron. As a functional unit of formation of urine serves nephron; in their each kidney there are about 1 million. Anatomic and functional components of nephron are discussed further. In the zone adjacent with brain, balls of nephrons differ from those more surface nephrons in which the loop of a ball goes to depth of a medulla; they play a different role in regulation of water-salt excretion. The ratio between cortical and yukstamedullyarny balls makes about 7:1.
Balls diameter on average of 150 — 200 microns serve as the filtrational device of nephron; in them primary urine is formed. Number of balls at the adult the same, as at a fruit with the body weight of 2 — 2,5 kg. Each of them differs in the difficult spherical gyrose capillary network formed by an afferent arteriole after its entry into a capsule. Walls of this network form a membrane through which there is urine filtering. They consist of three layers (fig. 13-3): 1) an endothelium gentle and rarefied with multiple openings, the polianionny glucoprotein superficial cover covering an endothelial plasma membrane (fig. 13-4); 2) the glomerular basal membrane (GBM), considerably gyrose, about 120 nanometers thick, having the central electronic dense bed and two rather electronic and transparent: internal subendothelial and external subepithelial; 3) the epithelium provided by rather big cells with the expressed cytoplasmatic shoots. By means of shoots these cells come into direct contact, to KBM. Between shoots there are filtrational cracks with a diameter of 24 nanometers.
Клубочковая долька с мезангием
Fig. 13-3. A glomerular segment with mezangiy.
Mm — a mezangialny matrix; MK — a mszangialny cell; MMK — mszhkapillyarny mezangialny channels; OE — an opening, or a crack, in an endothelium; EPK — an epithelial cell with a podocyte shoot; ENK — an endothelial cell; AF of the II NANOSECOND — respectively internal and outside layers of a basal membrane (the internal and outside rarefied plates); TsS — the central layer (a dense plate) [from: Orloff J., Berliner R. (eds). Handbook of Physiology. Sec. 8, 1973, p. 19].

The cover rich with polianionny glucoprotein covering epithelial cells and space between podocytes up to 80 nanometers thick differs in the negative charge caused by carboxyl groups of sialic acid.
The fixed negative charge on covers of endothelial and epithelial cells gives the chance to positively charged macromolecules freely to pass through walls of glomerular capillaries and detains macromolecules with a negative charge (fig. 13-5).
Except endothelial and epithelial cells to WHOM mezangialny cells contact. They lie deeply in the central part, or in a ball leg, and are separated from a gleam of capillaries by superficially lying endothelial cells. Mezangialny cells and intercellular substance (matrix) make a mesangium.
Электронная микрофотограмма эндотелиальной поверхности клубочковых капилляров в почках
Fig. 13-4. An electronic microphotogram of an endothelial surface of glomerular capillaries in kidneys of intact rats.
Numerous endothelial time, or openings are visible. Grebnepodobny educations (are shown by shooters) represent a local thickening of endothelial cells, X 24 000 [from: Brenner B. M., Rector F. Page, Jr., eds The Kidney. — Ed. 2. — Phyladelphia; WB Saunders, 198Ts.
Электронная микрофотограмма почечного клубочка
Fig. 13-5. Electronic microphotogram of a renal ball of intact rats.
Visceral epithelial cells, or podocytes (P), with the numerous shoots departing from their bodies to capillary loops are visible. Directly they are adjoined by legs from different podocytes. X 4800 [from: Brenner B. M., Rector F. Page, Jr., eds. The Kidney. — Ed 2. — Phyladelphia: WB Saunders, 1 — 81].
The macromolecules (for example, cell-bound immune complexes) passing through glomerular capillaries can enter a mesangium through a gleam between endothelial and mezangialny cells and migrate on intercellular channels towards juxtaglomerular area in which settle. The mechanism of this process is still poorly studied. Macromolecules can be englobed by mezangialny cells or infiltriruyushchy phagocytes. Thus, the mesangium, apparently, works as a component of reticuloendothelial system in glomerular circulation, taking and besieging some substances with a big relative molecular weight. The Mezangialny area represents the major site which is involved in process at some diseases which are followed by changes in balls. Sometimes they proceed nonspecific (cellular and matriksny proliferation), sometimes with more specific and even pathognomonic signs (for example, intra capillary nodular educations at a diabetic glomerulosclerosis).
The ball is surrounded with a capsule. Its basal membrane serves as continuation of a basal membrane of a proximal gyrose tubule and lies on the interior of covering epithelial cells. The canalicular part of nephron begins from the opening in a capsule which is usually located opposite a vascular pole.
Tubules. Distally in relation to a ball nephron turns into a tubule. Its separate segments are characterized by localizations, histologic signs, physiological functions inherent in them. The tubule, a ball loop, a distal tubule, a collective channel are a part of a segment proximal gyrose. From the point of view of embryology, the collective channel does not belong to nephron, but represents structural and functional speak rapidly it. Throughout tubules are surrounded with the continuous basal membrane connecting to KBM. The basal membrane of tubules provides a continuous basis for their epithelium.
Proximal gyrose tubules are localized in bark, differ in big diameter and are covered with a cubical single-layer epithelium. The spherical kernel is on a basal surface of a cell. It is difficult to define space between cells even at electronic microscopic examination, but it carries out an important role of the channel from which solutions and water reabsorbirutsya by cells, pass into the capillaries surrounding tubules. The brush border increases a reabsorbtsionny surface of cells and densely fills a gleam between them. This connection is rather impenetrable for solutions or water, but probably the return diffusion of reabsorbiruyemy solution and water in a gleam of the channel is carried out with its help. Numerous mitochondrions of cells of proximal tubules borrow 2/z basal part of a cell. The basal surface of each cell of a tubule (a basal plasma membrane) forms the numerous folds adjoining to mitochondrions. The capillaries surrounding tubules are in close proximity to a basal membrane. Cells of proximal tubules participate in transfer or a reabsorption from their gleam of large amounts of water or solution, and also in the course of canalicular secretion at the expense of the substances arriving from blood vessels or synthesized in cells and which are emitted in canalicular liquid.
The loop of a ball represents continuation of a proximal gyrose tubule. Its length varies depending on localization of a ball in a bast layer. Nephrons with the balls located in outside 2/3 him possess very short loops or the last are absent, and 1/3 layers located in internal differ in the longest loops reaching nipple top.
After descent in brain part the loop turns back in a bast layer and becomes in it a distal tubule. An epithelium in the descending part of a loop flat and scaly; diameter of tubules is much less, than in proximal part. This department is called a thin segment of a loop of a ball which can be limited to the descending part or form a bend and proceed on the ascending part of a loop. The surface of cells turned into a gleam is supplied with the short, seldom located microvillis in which cytoplasm seldom find mitochondrions. The ascending branch (a thick segment) it is covered with thicker epithelium which kernels are localized in lyuminalny part of cells. Numerous rhabdoid mitochondrions occupy basal part of cells, short microvillis depart from their lyuminalny surface. Deep folds of a basal plasma membrane promote close contact with mitochondrions.
The ascending part of a loop of a ball passes into distal tubules. The initial part (straight line) goes directly to a ball. As soon as the distal tubule passes a ball, it contacts to an afferent arteriole; this part of a tubule is known under the name macula densa. Then distal tubules turn into gyrose; cells of their cubical form soderyasat in consolidation cytoplasm in the form of large granules and numerous mitochondrions. In apical cells more often than in basal, kernels are visible. The surface of cells turned into a tubule gleam is supplied with short microvillis, larger and less plentiful, than in cells of proximal tubules.
Sobiratelny Canal forms at connection of two or more terminal segments of distal gyrose tubules and receives additional branches on the way to a nipple. An epithelium in this part idle time cubical. It is a final segment of nephron; he unites to one of collective tubes through which urine from the general channel gets to a small cup.
Intersticial fabric. The intersticial space and number of cells increase about nipples. The space is filled with substance of low electronic density. Distinguish several types of intersticial cells. The type I is most numerous, cells remind it fibroblasts, cells like II have some similarity to one-nuclear cells and cells like III can possess phagocytal activity, or pericytes, are localized in close proximity to direct vessels.
At electronic microscopic examination in cells like I it is possible to see numerous fatty little bodies and abundance of endoplasmic educations. Marrow of kidneys is a place of synthesis of prostaglandins; it is probable that predecessors of prostaglandip of PGE2 and PGF2a contain fatty drops.
Innervation. Kidneys are rich with adrenergic and cholinergic nerve fibrils. They pass mainly along blood vessels, i.e. along interlobar, arc-shaped, interlobular arteries and afferent arterioles. Some fibers innervate the yukstamedullyarny efferent arterioles going to direct vessels. The nervous system of kidneys plays a role in regulation of a blood-groove and glomerular filtration rate. Stimulation of sympathetic fibers is followed by reduction of speed of a blood-groove in a bast layer and reduction of excretion of sodium, and their blockade leads to vasodilatation of kidneys and increase in a natriuresis.



 
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