PHYSIOLOGICAL AND ANATOMICAL FEATURES OF THE RENAL SYSTEM IN CHILDREN. SEMIOTICS OF MAIN RENAL SYSTEM DISORDERS (PYELONEPHRITIS, GLOMERULONEPHRITIS ETC). SEMIOTICS OF MICROSCOPIC CHANGES URINE SEDIMENTATION ( PROTEIN ERYTHROCYTE, LEUKOCYTE AND CASTS) ACUTE AND CHRONIC RENAL FAILURE SYNDROME.
Anatomical and physiological features
The formation of kidneys happens in the middle of the third week of life of a fetus. They develop very fast, and already at the end of the 9th week of gestation period, kidneys begin to function and the discharge of urine takes place through placenta (though excretory function is not fulfilled by the kidneys at this time). Thus, the embryological period of a fetus is critical for the urinary system.
The characteristic features of kidneys after birth:
· Kidney’s capsule in a newborn is very thin.
· Up to 2-3 years of age kidneys have segmented structure, later on these segments are connected, and each kidney represents a separate whole organ.
· The considerable physiological mobility of kidneys at early age is due to poor development of ligaments, which fix them in position.
· Ratio of kidney to body size in a newborn is comparatively larger and kidneys are situated lower than in an adult; age features of the position of the lower pole of kidneys are the following:
§ Newborn — is lower than the spine of the iliac bone.
§ 1 year — at a level of the iliac bone.
§ More than 3 years — on 0.5-1 cm above iliac bone.
§ The right kidney is located 0.5-1 cm lower than the left kidney.
Nephron — a functional unit of a kidney — consists of renal corpuscle and the system of tubules.
In connection with the repeated request of the students we shall consider the structure of nephron.
Renal corpuscle is a glomerule of blood capillaries, surrounded by a double-walled sheath (simple squamous epithelial tissue) called Shumlyanski-Bowman’s capsule (native scientist of the 18th century and English scientist of the 19th century). This renal capsule passes into the system of tubules which consists of following parts:
Proximal convoluted tubules, considerably curved at the beginning, at the medullary stratum of kidneys becomes more straight.
Henle’s loop (German scientist of the 19th century):
· Descending part (thinner).
· Curving — in a medullary stratum in the form of the U-shaped loop.
· Ascending part — in the cortex substance (wider).
Distal convoluted tubules (straight, then sinusoidal) is reverted its glome rule.
The total number of all nephrons of both kidneys is 2 000 000, thetotal length of canals is 60-80 km. Then, as a result of the connection of distal tubules, collecting tubules are formed, which are reverted into medullary substance. The last ones are connected again, to form the papillary ducts. They open in renal ducts transferring into minor calyces. Several minor calyces unite to form 2-4 major calyces. Major calyces open into the renal pelvis. From the contracted part of renal pelvis ureter goes out.
The ureter has the winding form and 3 physiological contractions: going out of renal pelvis, at transition into the cavity of a true pelvis and in the place of an inlet into the urinary bladder. The place of joining is 2 cm above the pubic symphysis. An anatomic feature for children of infant age is the small length of an intravesical segment of the ureter (about 5 mm), situated already in the thicker wall of the urinary bladder, 11 can lead to flow of urine from the urinary bladder upwards. In some cases the urine can hit into renal pelvis, a phenomenon known as vesicoureteral reflux. The reflux is not present in children of older age, when the segment gains more length.
The capacity of urinary bladder is most intensively enlarged during the period of the 1 year — by 5 times (at 1 year of age it becomes equal to 200 ml). Children’s urinary bladder is situated much higher than in adults, thence a palpating its edge becomes possible when it is filled up with urine. After the breast feeding age, deceleration of body growth is observed. Simultaneously there is lowering of urinary bladder into the cavity of the smaller pelvis.
The neck of urinary bladder passes into urethra (urogenital canal), the length of which for the boys and girls in neonatal period is equal to 5- -6 cm and 1-2 cm respectively, at school age — 10-12 cm and 3-5 cm respectively.
Blood circulation of kidneys and the mechanism of derivation of glomerular capillaries
From abdominal part of aorta, two renal arteries come out, which in the field of the helium of kidneys start to get divided into branches (interlobar arteries), that lasts in substance of medulla and cortex. The interlobar arteries in cortex substance give a branch to every renal corpuscle (this is an afferent renal arteriole (vas afferens) As a result of its division on 15-20 loops the glomerule of capillaries will be derivate. Then from each renal corpuscle comes out one efferent renal /glomerular) arteriole (vas efferens).
The arterioles through the network of capillaries pass into venous system. The renal vein runs into vena cava inferior.
Bloodstream, passing through kidneys, carries out two functions — the formation of urine and blood supply to kidneys.
Functions of kidneys
Excretory function (clearing) — the excretion of metabolic waste products from an organism, and of unnecessary substances at their excessive amount, and also of unwanted foreign substances which have got into an organism.
From the waste products of metabolism of nitrogenous substrates: urea, uric, acid, creatinine and other substances are excreted.
Homeostatic — maintenance of a constant internal environment of an organism (pH, water-salt, protein, fat, carbohydrates exchange, temperature, osmotic pressure, etc.).
Secretory — there is derivation of many substances in the kidneys, for example:
· Erythropoietin — the stimulator of an erythrogenesis in the bone marrow.
· The final derivation of the active form of vitamin D3 — promotes the absorption of calcium into the intestines.
· Renin is involved in the initial phase of the angiotensin-aldosterone system, and this system regulates water metabolism, (its influence oeurones of the brain causes the feeling)
· Ammonia — is the impulse for respiratory and nervous systems, etc.
Anamnesis of disease and life
The rules of collecting anamnesis of the illness of the pathology of kidneys and urinary system are identical to the repeatedly surveyed order — the first day of the disease, clinical sign and their changes, the treatment carried oul in home conditions (dose and duration of taking medicinal preparations); at presence — the results of laboratory and other ways of inspection, the day of hospitalization, dynamics of the pathology in the hospital.
Special attention is necessary for diseases, which, probably, the child had 10-15 days before pathology of kidneys developed (acute tonsillitis, pneumonia, scarlatina, etc.). Usually the worrying parents do not speak about such diseases, as, in their judgment; there is no correlation between the former pathology and kidneys. Actually, quite often approximately in 2 weeks the transfer of the infection from respiratory and other paths in the renal system appears.
At collection, of the anamnesis of the life of the 1st year child it is necessary to collect the obstetric anamnesis, as the infectious diseases which the mother used to have during her pregnancy could cause an inflammatory diseases of kidneys for a fetus.
The sign of the complicated premorbid background on the 1styear of life are: rickets, anemia, atopic dermatitis, hypotrophy, artificial feeding, etc.
Physical examination
At examination of the patient it is necessary to estimate the following signs:
Consciousness.
• Response to the surrounding.
• The behavior — at a renal colic the child rushes about, caot be quiet.
• The color of the skin integuments.
• The position in bed — a characteristic sign of the purulent — inflammatory process in the perirenal fatty body is the forced position, when the child lies sideways, the leas are bent at the knee and coxofemoral joints and are put closer to the trunk.
• Edema.
• The presence of possible asymmetry of the body in the projection of kidneys, even of the abdomen (if the tumor of kidneys of big size is present).
• The bulging of the urinary bladder above pubis — a sign of the considerable urine detantion.
Palpation and percussion
Taking into account the age features of the position of the lower pole of a kidney, II becomes clear that normally it is possible to palpate this organ only in children of the first 2-3 years of life. At senior age the kidney can be palpable only, in case of its increasing (tumor, stones of kidneys) and displacement downwards.
Methods of the conjoined manipulation
1. Method of Obraztsov-Strazhesko:
· The position of the child is horizontal.
· The doctor is on the right side of the patient.
· As you have already learnt method of palpation of the organs of the abdominal cavity, the legs of the child are a little bent and are slightly abducted (this movement partially relaxes the muscles of the abdominal wall).
· The patient does regular respiratory movements.
· Palpation of a right kidney:
ü The left hand of the doctor is under the trunk in the projection of a right kidney (along the waist).
ü The right hand of the doctor lies flat lateral from the right rectus muscle of the abdomen (in a parallel way to it), the fingers are posed a little bit below from the right costal arch.
ü In such a position, during the process of exhalation, the right arm gradually goes deeper inward. The palm of the left hand is simultaneously raised upwards, which promotes the approximation of the kidney to fingers of the right hand. Thus, in case of possible palpation of kidneys the right hand at the beginning feels the lower pole of a kidney. Further sliding movements estimate the sizes, form, mobility, morbidity, consistency, possible roughness of the wall of the right kidney.
ü The palpation of a left kidney the technique corresponds to the above described, with one exception: the left hand will be carried on further under the trunk up to the projection of a left kidney, the right one is allocated outside, in the area of the left musculus rectus abdominis.
2. Guyon’s method (French urologist of the 19,h-20th centuries) (method of balloting). The common rules (position of the patient is horizontal) correspond to the previous ones. At palpation the doctor does fast pushing with his/her left hand (so that the pushing force is felt with his/her right hand). Thus, the kidney li will rise up and the doctor will feel the signs of the palpated organ better.
3. Israols’s method (German surgeon of the 19th-20th centuries):
· The patient lies — on his/her right side on palpation of the left kidney and on the left one — at the palpation of the right kidney.
· The child brings legs closer to the abdomen, inflexing more — the one corresponding to the side of the palpated kidney.
· Then at the end of inspiration and at the beginning of exhalation the doctor does the active bimanual palpation (which is described above). having fixed the fingers of the palpating hand on the front of the trunk 3-4 cm belove than the IXth-Xth ribs.
4. Botkin’s method is similar to Obraztsov-Strazhesko’s method except the position of the patient — it is vertical. This way is more applicable when there is a i.niKiiderable mobility of kidneys, as on standing position kidneys tend to descend.
5. Hnatyuk’s method (modern Ukrainian pediatrician). The doctor faces the patient, who is in vertical position. Then the patient bends forward (the trunk is at the angle of 90°) and the doctor carries out the palpation of kidneys with the help 0l li us earlier explained method. Such a position of the patient relaxes the muscles of the abdominal wall which allows the doctor to enter his hand more deeply.
6. There is one more variant of the palpation of kidneys in vertical position, win mi the patient is bent forwards. The doctor in this case stands behind the child. Fixes the right palm on the skin of the abdomen according to the projection of a kidney, puts fingers deep into and palpates the organ from below upwards with sliding movement.
The objective sign obtained in diseases of the renal system is the detection by palpation of the ‘pitting’ edema.
One of the first, quite objective in pediatrics, professionally favorites of the doctors among clinical signs of diseases of kidneys is the Pastematsky’s symptom (native therapeutic of the 19th century), defined with the help of the method of slight beating as percussion. The essence of the method consists in the arising of the pain in the location of kidneys.
Variants of the technique
1. The doctor places the palm of his/her left hand in a horizontal position on the loins in the projection of a kidney (it is the angle between XIIth rib and periphery edge of long back muscles, or costo-vertebral angle.
Then with the edge of the hand or with the fist (it is not a mistake!) of the right hand the doctor does 2-3 slight beatings on his/her left hand.
The first beating must be very slight. If the child does not react to it, i.e. pain is not present, it is possible to make 2-3 times more harder beatings.
The technique is done on both sides.
The absence of pain means that Pastematsky’s sign is negative, the presence of a pain shows its presence. In case history, it is possible to write so or to make accordingly a record of the other sort — Pastematsky’s symptom (-) or Pasternatsky’s symptom (+). It is necessary to specify the defected side, for example: Pastematsky’s symptom (-) on the right and (+) at the left.
2. The technique can be fulfilled only with one hand — right, doing the beatings on the skin of the child in the projection of kidneys. At a weak defect of kidneys the first method can give the negative information, and second — the positive one.
3. And the following method of determination of Pastematsky’s symptom is especially good for the little children. With the edges of both hands slightly pressing it is necessary to pass along the back part of the waist from outside inside, i.e. in the projection of kidneys. If some contractions of muscles are felt by this — Pastematsky’s symptom is (+).
It is necessary to note, that Pastematsky’s symptom in pediatrics is an auxiliary method at diseases of the renal system only in children older than 2 -3 years, as at early age ‘a kidney is not painful’. The kidney has segmented structure there is no united sheath, but it is the sheath that pains at the extension (pain receptors are located on the capsule).
By the method of the percussion it is possible to spot a higher boundary of the urinary bladder. The silent percussion is done along the median line of the abdomen from above the navel downwards till the appearance of ii dull sound (a mark will be put above the finger-plessimeter).
The results of the percussion are:
· Normally, there should not be dullness.
· The decrease in resonance after urination — is a sign of the presence of some residual urine.
· The higher boundary of the urinary bladder is marked, the more it is filled with urine.
Additional methods of inspection
General urinalysis
After washing external sexual organs of which is compulsory, the whole amount of urine first micturated in the morning is collected into a clean but not sterile vessel. The normal data of urine routine and their deviation has been discussed above.
If necessary, the amount of protein in daily urine is determined, which is normally 130-50 mgl (sometimes 100-150 mg is admitted).
As you can see, at considering the analyses the indicated parameters were not very precise. In this situation the conclusion is made: if you are not absolutely sure about the authenticity of the results of the investigation of the patient, repeat the same analysis the next day, in some days, compare the obtained results, compare the data obtained by several methods, and also correlate the data obtained from the analyses with clinical symptoms.
One of the most widely used methods for defining the number of blood cells (and hyaline cylinders) in urine are the methods of Nechiporenko, Hamburger, Addis sediment count. You might ask what is the need of these tests when the number of leucocytes and erythrocytes is already determined in general urinalysis. The fact is that general urinalysis is not accurately exact. And if the data of it correspond with the normal, and the results of more precise analyses mentioned above indicate some pathologic deviations, then the child has the disease of the kidneys or urinary paths.
Urinalysis by Nechiporenko
(native urologist of the 20lh century)
This method determines the amount of leukocytes and erythrocytes (and cylinders) in 1 mL of urine.
The rules of collection: the middle portion of the first morning micturated urine, not less than 10 ml, is collected in a clean vessel. As you can see, the method is very simple.
The normal parameters are:
Leukocytes — not more than 4000 in 1 mL of urine
Erythrocytes —not more than 1000 in 1 mL of urine
Hyaline cylinders — not more than 250 in 1 mL of urine
The urinalysis by Hamburger
(French nephrologist of the 20th century)
This method determines the amount of blood cells in urine which are passed out within 1 minute.
The rules of collecting urine for the analysis:
· On the eve the child should not take a lot of liquid and should not drink anything during the night.
· The first morning micturation should not be taken (it is also possible to use this urine for general urinalysis, by Nechiporenko), the time of the first micturation is precisely noted.
· After 3 (!) hours all the urine passed by the child is collected in a clean vessel and sent to the laboratory.
The normal parameters are:
|
Leukocytes |
not more than 4000 |
|
Erythrocytes |
not more than 1000 |
|
Hyaline cylinders |
not more than 250 |
The interpretation of the results is similar to the analysis of results by Nechiporenko.
Addis sediment count
(U.S. doctor of the 20th century)
This method determines the amount of blood cells and cylinders in the 24 hours amount of urine.
The rules of collecting urine for the analysis:
· On the eve the child should take more protein rich food, less liquid and should not drink anything iight.
· In the evening before sleeping it is necessary to note the time of the last micturation.
· Then during 12 hours it is necessary to collect urine in one vessel (in the laboratory the calculation will be done for 24 hours).
The normal parameters are:
|
Leukocytes |
not more than 4 000 000 |
|
Erythrocytes |
not more than 1 000 000 |
|
Hyaline cylinders |
not more than 20 000 |
The significance of every investigation is in the order seen above: the analysis by Nechiporenko is more precise, than general urine test, the analysis by Hamburger is more objective, as compared to the method of Nechiporenko, and the Addis sediment count is most reliable (this method is useful at diagnosing the latent forms of pyelonephritis and glomerulonephritis).
Possible versions of the analysis:
• Considerable leukocyturia. may be insignificant hematuria and cylindruria — the sign of pyelonephritis.
• Considerable hematuria (less expressed leukocyturia) and cylindruria — the signs of glomerulonephritis.
• Considerable leukocyturia (hematuria may be present), and cylinders iormal quantity — often the sign of inflammation of the urinary tracts.
Urinalysis for bacteriuria and sensitivity to antibiotics
The presence of pathogenic bacteria in urine is a diagnostic sign of inflammatory process in kidneys and urinary tracts. The rules of the analysis:
· The urine is collected in a sterile (!) vessel (in a tightly closed test tube from the bacteriological laboratory or, as the last resort, in a glass vessel sterilized for 45 minutes, covered with sterile wax-paper).
· It is necessary to wash the child well before collecting the urine.
· It is desirable to take the midstream or end portion of urine as tho first part washes the external genital organs which always contain various flora.
· After collecting the urine the container should be closed tightly.
· Minimum amount of the collected urine is 1 ml.
· The time from taking urine till giving to the bacteriological laboratory should not exceed 2 hours (if the duration of this period increases, the composition of urine changes).
The result comes in 3-7 days.
The diagnostic evaluation
For a long time it was considered that even in healthy children the number of microbes (the amount of pathogenetic flora in 1 mL of urine) can be up to 100 000; more than 100 000 is a sign of bacteriuria.
However, nowadays according to the findings of many researches the increase in the microbial number more than 50 000 in 1 ml is irrefutable sign of inflammation of kidneys and urinary tract.
The result of 10 000 – 50 000 bacterial flora in 1 ml of urine in the first analysis is a sign for suspecting true bacteriuria. If the same kind of data appears during repeated analyses in some days, it means the child has the inflammatory process in the kidney.
If the result is less than 10 000. or negative (absence of pathogenic flora in the urine), then the conclusion is normal.
Besides, in the analysis with the increased amount of bacterial flora it is indicated what kind of flora is inoculated (staphylococcus, Proteus vulgaris, etc.), and the sensitivity of bacteria to antibiotics is also to be found.
Three-glasses test
With the help of three-glasses test it is possible to determine approximately the source of RBC in urine. The name of this method is figurative. The essence of the method is as follows. During one micturation the child should urinate into 3 glasses: the initial portion — into the 1st glass, midstream portion — into the 2nd, and the end portion — into the 3rd glass.
However, it is not necessary for the child to urinate into 3 glasses or some other vessel. It is enough just to estimate the color of urine visually during the whole time of micturation.
The diagnostic evaluation
If the urine has red color only in portion I, and then — hay-yellow, the hemorrhage is the result of urethritis.
If the color of blood is observed only at the end of micturation (portion III), it is a sign of coming of erythrocytes originating in the urinary bladder:
· At its maximal contraction and damage of the mucous membrane by accumulated sharp stones.
· At release of red blood cells during cystitis,
· From tumor tissue.
The red color of the urine in all three portions means the erythrocytes come from the kidneys.
Investigations to determine kidney functions
The purpose of the method considered below is to test the functional reaction of kidneys to metabolism in the human body and the ability to regulate osmotic homeostasis.
Zimnitskiy’s test
(native therapeutist of the 19th-20th centuries)
It is a method to determine the functional ability of kidneys to osmotic concentration and osmotic dilution. Rules and features of the method:
· The first micturation (usually at 6.00) — in a place of common use (as a matter of fact, such a situation has already been mentioned, this portion can be used for general urinalysis, analysis by Nechiporenko, for bacteriuria which will speed up the investigation of patient).
· Then every 3 hours (9.00; 12.00; 15.00.; 18.00; 21.00; 24.00; 3.00; 6.00) the child urinates every time into one of the separate numbered (or time denoting) vessels.
· Usual diet during the day.
· If the child needs urinating in an interval between the indicated times, he/she should urinate into the next vessel (for example, at 10.00 urinate into the vessel for 12.00), and then, when the time for the next urination comes, the child should urinate into the same vessel (12.00 again).
· If at any time the child does not have urine, the vessel remains empty.
· The vessels, including the empty ones, are given to the laboratory after collecting all 8 portions.
· For children of younger age it is possible to use the method of Zimnitskiy, a little adapted, — urines collected at the moment of natural micturation and the number of vessels corresponds to the number of urinations.
While estimating the results, the following data are taken into account:
· The amount of the urine passed out during the day.
· The ratio between day time (first 4 portions) and night (last 4 portions) diuresis that is the index of the rhythm of kidneys activity during the day.
· Parameters of specific gravity (relative density) of the portions of urine and their change throughout the day — maximal is the index of the ability of kidneys to concentrate urine, and minimal — to dilute it.
The diagnostic evaluation
1. The total quantity of urine passed during the day depends on the age /Do you remember the formula V = 600 + 100 (n – 1)?/and constitutes approximately 2/3-3/4 of the volume of the taken liquid. Positive sign of the adequate reaction of kidneys to metabolism in children is considerable change in the quantity of urine in the different portions.
2. Normal correlation of day time and night diuresis — 2 : 1
3. The normal parameters of specific gravity depend on the age.
The second sign of normal functioning of kidneys is the change of the relative density of urine in different portions. Normally the difference between the maximal and minimal figures should not be less than 7. The better the kidney functions are preserved, the more the fluctuation in specific gravity is.
Variants of disorder and their causes:
(a) Based on the 24 hours amount of urine:
• Oliguria (acute renal failure — ARF, nephritis, formation of edema of cardiac and renal character, vomiting and diarrhea at diseases of gastrointestinal tract, intoxication with hyperthermia, etc. — / think that here and further on the mechanism of deviation is clear).
• Anuria (ARF).
• Polyuria (Diabetes, period of decrease of edema)
(b) Based on the ratio of day time and night diuresis — nocturia (a sign of decrease in the functioning of kidneys of renal or cardiovascular character).
(c) Based on specific gravity:
• Hyposthenuria — low specific gravity — in all portions the relativn density is below normal parameters; for example, after 2 years of age —1002-1010, which points at the decrease in the ability of kidneys to concentrate urine (renal insufficiency — the filtration function is decreased; period of disappearance of edema, diabetes insipidus).
• Isosthenuria — variation of specific gravity very low (2-5 units). usually stay at the level of 1010-1012. that corresponds to the density of blood plasma; it signifies the decrease in the function of kidneys concerning dilution and concentration (a serious form of the disease — renal failure).
• Hvpersthenuria — high specific gravity — 1025-1030 (a sign of the decrease in the osmotic dilution of urine; can be at considerable decrease of the amount of the passed urine of extrarenal genesis).
Excretory urography
The purpose of the excretory urography is to find out the form, size, position, and also the function of kidneys and ureters. For contrasting the urinary tracts, which is the essence of the method, special contrast substances (Urografin, etc.) are used, which are introduced into the blood vessels and are taken out by tho kidneys later on, after getting to bloodstream. The test on all preparations should be carried out 2-24 hours before the investigation. The dose of a medicine in decided according to the instructions depending on the age and body weight of the child. Sometimes the drug is introduced intramuscular and also per rectum.
X-rays are taken 5-7 minutes after intravenous introduction of the contrasting substance, further on — after 15-20, and then — 25-30 minutes. Thus, according to usual norms three X-rays are obtained.
Contraindications: severe renal insufficiency, uncompensated impairment of the heart and liver, intolerance to the contrast substance.
Ultrasound examination of the kidney and urinary tract — echourography
Echourography — is the most modern method of examination of patients with pathology of the kidneys and urinary tract. In comparison with oxcretory urography, it is safe and there are no contraindications.
Symptomatological disorders and diseases
Pyelonephritis
Pyelonephritis is a nonspecific inflammation of kidneys, mostly of bacterial character, with effection of the calyces, pelvis, interstitial tissue of parenchyma of kidneys and tubules.
Etiology: E.coli, staphylococcus, streptococcus, enterococcus, Proteus, etc.
The paths of the infection of kidneys:
· The hematogenous path — flora reaches kidneys from other organs, where the inflammatory process is present or was recently (tonsillitis, pneumonia, enterocolitis, sepsis, etc.).
· Uprising (urinoqenic = retrograde) path — the agent goes from below upwards along the lumen of ureter (the considerable frequency of such infection and case rate of pyelonephritis in girls is higher because of the anatomic structure of urinary tracts).
· Lymphogenous — by lymphatic system.
The main clinical symptoms of acute pyelonephritis
Common symptoms:
· High temperature (first 3-4 days of the disease).
· Weakness, flaccidity.
· Headache.
· Poor appetite.
· In connection with intoxication there can be vomiting, in small children — cramps and other signs of meningeal syndrome.
The skin — paleness, shadow under eyes.
The pain in the beginning of the disease is often localized in different sites of abdomen (suprapubic area, hypochondrium, in right and left flanks). Pain in fumbar area is characteristic as the complaint or as the outcome of examination (Pasternatsky’s symptom, etc.).
Disorders of urination — dysuria, pollakiuria, uracrasia, nocturia.
For putting diagnose, laboratory and others methods of examination are necessary, the main changes of which are:
1. Common urinalysis:
· Transparency — often turbid.
· Small proteinuria (up to 2‰).
· The reaction can be alkaline.
· Considerable leukocyturia, sometimes the number of blood cells can coat all in r/v and caot be counted.
· Single erythrocytes (mainly fresh).
· There can be leukocytic cylinders.
· Bacteriuria (remember that such a parameter in common urinalysis is not diagnostic).
2. The urinalysis by Nechiporenko (sometimes by Hamburger and Addis sediment counts — a considerable increase in the amount of leukocytes, can be a small rise in the amount of erythrocytes.
3. The urinalysis on bacteriuria — is detected as the considerable increase in the amount of pathogenic flora. Attention! The analysis can be close to normal values, if the urine passed on the background of the reception of antibiotics.
4. General analysis of blood — leukocytosis, shift of leukocytic formula to the left, acceleration ESR.
5. Echourography and if it will be necessary — excretory urography.
Cystitis
Cystitis is an inflammation of the urinary bladder.
Etiology: E.coli, staphylococcus, Proteus and another pathogenic flora.
The path of infection is similar to pyelonephritis.
Cystitis may be acute and chronic.
The clinical and laboratory data
Common state:
The healthy state of a child is violated mainly because of the below stated symptoms of the disease (disorder of urination and pain syndrome).
In spite of the fact that the disease has inflammatory character, the signs of common intoxication are expressed weakly (it is provided by weak absorption ability of the mucous membrane of urinary bladder and fast outflow of the agent with excreted urine).
Disorders of urination:
Pollakiuria (usually with small portions of urine) is the most typical symptom of acute cystitis.
Dysuria is also a frequent sign of the disease; the pain can be present before, at the beginning, during all the process of urination, however the most typical is the pain at the end of urination, when there is a maximal contraction of the inflamed urinary bladder with abundant innervation.
Severe pain can cause the contraction of the sphincter of urinary bladder and premature termination of urination, therefore the urine can remain in a great amount in the urinary bladder. Boys of early age can have complete ischuria.
Enuresis.
Objective inspection reveals the pain during palpation in suprapubic area.
The data of laboratory inspections:
· Urinalyses — leukocyturia. hematuria (fresh -!!!- erythrocytes), moderate proteinuria (up to 1 g/L). bacteriuria, three-glass test— (+) in the 3m portion.
· General analysis of blood — mild leukocytosis and acceleration of ESR.
Glomerulonephritis
Glomerulonephritis is the infectious-allergic disease of kidneys with dominant defect of qlomerules of the nephron.
Etiology: The cause of glomerulonephritis is mostly the B-hemolytic streptococcus of A group. Usually glomerulonephritis occurs in 10-15 days after a disease with similar agent (acute tonsillitis, complication of chronic tonsillitis, scarlet fever, etc.). The pathologies are promoted by cold, respiratory viral infection, introduction of serum, vaccines which can cause allergic reaction or are the factors of promotion on the background of streptococcal infection.
Acute glomerulonephritis
The glomerulonephritis is considered acute, if in 6-12 months all clinical and laboratory signs of pathological character disappear. A sign of convalescence is the complete remission (i.e. the absence of this disease) during 5 years.
For acute glomerulonephritis the cyclic course is characteristic:
· Initial period.
· Intense period of the disease (2-3 weeks)
· Period of return development (2-3 months-1 year).
If during 1-1.5 years on the background of treatment and constant hospital observation of the child any clinical or laboratory symptoms of glomerulonephritis are still observed, it is necessary to conceive about changing the disease transfer from the acute form to chronic.
The acute glomerulonephritis is classified into four forms:
1. With an acute nephritic syndrome (considerable defect of glomerulus and predominance glomerular component).
2. With nephrotic syndrome (simultaneous defect of tubules with considerable tubular component).
3. With isolated urinary syndrome.
4. With nephrotic syndrome, hematuria and hypertension.
The main clinical symptoms and laboratory analysis
Extra-renal signs:
· Flaccidity, weakness, malaise.
· The fever — usually up to sub-febrile.
· Paleness of dermal integuments.
· Vomiting.
· Hepatomegaly (sometimes).
· Edema — a very important symptom of great diagnostic value: at the beginning pasty, and then small edema which gradually increases, in the morning mainly on the face (a pale dropsical face, probable bloating of cervical veins — all this results in characteristic look — Fades nephritica).
In the evening the edema appears on the legs. Then the edema can gain generalized character, down to accumulation of fluid in pleural and abdominal cavities.
The pathogenesis of edema is stimulated by many factors, on the basis of which they can be:
ü Osmotic edema — if in a patient the filtering in glomerules reduces (it raises the amount of sodium and water in blood), if the reabsorption of water in tubules increases (under the influence of higher synthesis of antidiuretic hormone – ADH) and sodium (under the influence of ADH and Aldosterone), the sodium, which has collected in blood, goes from vessels with the purpose of support of the osmotic homeostasis into tissues and water there; the developed hypertension also is the cause of transition of water into hypodermic cellular tissue — soosmotic edema appears being a characteristic symptom of the nephritic form of glomerulonephritis.
ü Oncotic edema — a characteristic sign of the nephrotic form of glomerulonephritis, when in connection with the defeat of tubules the reabsorption of protein is violated (considerable hyperproteinuria), therefore hypoproteinemia develops, and the decreasing of the oncotic pressure results in going of water into tissues — so the oncotic edema develops,
· Rise in BP — by 20-30 mmHg, equally both systolic and diastolic pressure are increased; the rise in BP is shown by headache, vomiting, tachycardia, auscultation — systolic apex murmur. The mechanism of hypertension is the following: at decrease of the blood circulation in kidneys the activity of juxtaglomerular apparatus also increases and the synthesis of renin rises, then as a result of interaction with angiotensinogen of blood the angiotensin I will be derivated, after which the angiotensin II appears, which, the first, raises the blood pressure immediately and the second, raises the secretion of aldosterone of adrenal glands (it maintains sodium and water and also increases the volume of circulating blood).
Renal signs:
· Positive Pasternatsky’s symptom.
· Pain during the deep palpation of kidneys.
· Urinary syndrome:
ü Oliguria, oliooanuria (caused by decrease in the amount of functioning nephrons and decreasing of their filtration ability, and also the rise of reabsorption of water in tubules).
ü Urine — ‘smoky brown’ (characteristic symptom of the nephritic form).
ü The high relative density of urine (more than 1030).
ü Proteinuria (mainly Albumins penetrate) — almost an obligatory sign of glomerulonephritis. The proteinuria is caused by hyper-permeability of glomerulus on the basis of the defect of podocytes, basal membrane and endothelium of capillaries, and also the decreasing of reabsorption of proteins in tubules.
ü Leukocvturia — not very high (20-30 in r/v), is noted approximately in 1/2 -1/3 of cases on the first day of the disease.
ü Hematuria — 100% symptom of glomerulonephritis. There can be macrohematuria (glomerular component) and microhematuria (tubular component) with predominance of lixivious erythrocytes — pathognomonic sign. In connection with the rupture of vessels there can be a small amount of fresh erythrocytes.
ü Cylindruria — hyaline, granular, bloody, in severe cases — epithelial and waxy; expressed proteinuria and cylindruria are the symptoms of stratification of tubular component on glomerular.
ü Higher amount of epithelium in renal tubules.
Protein spectrum of blood:
· Hypoproteinemia.
· Disproteinemia.
· Hypoalbuminemia.
· Decrease of A:G coefficient.
· Hyper-a2-globulinemia and hyper-y-globulinemia.
Functional renal tests — in the initial period at oligoanuria there can be a small rise of rest-nitrogen, urea and creatinine. General analysis of blood:
• Decrease in the amount of erythrocytes and hemoglobin — normochromal anemia.
• Low neutrophilic leukocytosis.
• Eosinophilia.
• Acceleration of ESR (up to 30-40 mm/hr).
Acute renal failure
Acute renal failure (ARF) is a sudden sharp violation of different kinds of functions of kidneys (delay of the excretion from an organism of the products of metabolism of nitrogenious substances, disorder of water-electrolyte exchange, hormonal regulation, secretory function, etc.).
Etiology of ARF: All the causes are divided into three groups according to the place of their localization:
· Prerenal — shock of different genesis (bacterial, anaphylactic, posthemorrhagic, post-hemotransfusion, burn, traumatic), spasm of renal vessels under the influence of medicine or their block at thrombosis, embolism, etc.
· Renal — anomaly of a kidney in the form of its absence, necrosis of kidneys at poisoning (under the influence of medicine, salts of heavy metals, mushrooms or poisonous substance); as a repeated complication on the background of uncured prerenal ARF, etc.
· Postrenal — block or pressing of urinary paths (urolithiasis, tumor, inherent anomalies).
The clinical aspect of ARF has four stages.
1. Initial (shock) — arises in 1-2 days after the attack of the etiological factor, last for 1-3 days and the following symptoms are observed at this:
· Decreasing of diuresis.
· Decrease of the relative density of urine.
· In blood — rise of rest nitrous products and potassium.
· Symptoms according to the etiological factor (for example, at incompatible blood transfusion — the signs of hemolysis of erythrocytes).
2. Oliqoanuric stage, which can last about 2-2.5 weeks, and such symptoms are characteristic for it:
(a) Urinary system:
· Oliguria passes into anuria.
· Low relative density of urine — about 1005-1008.
· Transparency of urine — turbid.
· The color of urine — dark, brown, red.
· Macrohematuria.
· Leukocyturia.
· Much renal epithelium.
· Cylindruria.
(b) The state of water-mineral metabolism depends on the kind of its violation; it can be as hyperhydratation (often) or dehydration (rarely — in insidence of vomiting and diarrhea).
(c) The analysis on renal tests — rise of rest-nitrogen (can be 5 times more), urea and creatinine. The developing hyperazotemia clinically will be exhibited by:
· Fever.
· Headache.
· Anorexia.
· Anxiety, then sleepiness, lethargy (sluggishness).
· Itching.
· Hepatolienal syndrome.
(d) In connection with passing of rest-nitrous products through the gastrointestinal tract the following symptoms arise: pain in the abdominal cavity, nausea, vomiting, diarrhea, meteorism, patch like changes on the mucous membrane in the inform of stomatitis, gastritis, enterocolitis, etc.
(e) Blood analysis on electrolytes (see the section ‘Water and mineral metabolism’). During ARF, excretion of all electrolytes is impaired, but (Attention!) their concentration in blood depends on etiology, pathogenesis and seriousness of disease. Beside, concentration of some ions increases while that of others decreases.
Ussually, there is an increase in concentration of potassium, magnesium and phosphorous and consequently the following changes occur:
· Hyperkaliemia — one of the most dangerous signs of ARF (don’t arise in every case). Basic causes: considerable reduction in glomelural filtration (hence excretion of potassium by the kidneys), destruction of muscular tissue, an increased catabolism and hemolysis. As a result of it, cellular potassium comes out to the extracellular fluids. Attention! On frequent vomiting and considerable diarrhea potassium is excreted from organism in large amount. Due to this fact, hyperkaliemia will not occur. Hyperkaliemia will be exhibited by changes on ECG which have major diagnostic value, muscle weakness down to the development of paresthesia, paralysis, arrhythmia and even cardiac arrest.
· Hypermagnesemia — it occurs when excretion of magnesium has been impaired as a result of a reduction in glomelural filtration by kidneys and due to a vast destruction of tissues and hypercatabolism Hyperphosphatemia — it occurs when excretion of phosphorus has been impaired as a result of a reduction in glomelural filtration by kidneys.
· Ussually, there is a decrease in concentration of other electrolytes and consequently the following changes occur:
· Hyponatremia and hypochloremia. Remember by nature sodium and chlorine are extracellular electrolytes. Mechanism of decreasing is following:
ü Most important — on oligouria and anuria, quantity of water in body increasing resulting into hydremia. If the retained water is proportionally more than the retained electrolytes, then the concentration of the latter will decrease. More water in the body implies less concentration of the electrolytes.
ü Apart from that, there occurs an influx of sodium and chloride ions into the cells. Attention! A decrease in concentration of the electrolytes develops if there is no extrarenal loss.
· Hypocalcemia. Pathogenesis:
ü As a result of hyperphosphatemia (see above) there is a formation of insoluble calcium-phosphate crystals, which accumulate in soft tissue.
ü Impairment of the transition of vitamin D in its active form, something that leads to the distortion in the absorption of Ca2+ in the intestines.
· On the background of developing metabolic acidosis, and also of mentioned hyperazotemia there are violations concerning all systems:
ü Dermal integuments — paleness, icteritiousness, hemorrhage.
ü The cardiovascular system—tachycardia, later on —bradycardia, extrasystole, block, more frequent decreasing of BP.
ü Respiratory system — dyspnea, pathological types of respiration (Cheyne-Stokes, Kussmaul), edema of lungs.
ü Hemopoietic system — depressing of hemopoiesis (normochromal anemia).
3. The stage of restoring of diuresis (the stage of polyuria) for about 1.5 months. It is a favorable prognostic sign, which indicates the restoring of permeability of kidneys’ tubules. In connection with available at the beginning of the stage inferiority of epithelium of tubules, reabsorption and secretory functions in them are not fulfilled completely and, thus, some temporary features of such symptoms are stipulated:
(a) At the beginning of the 3rd stage there is an increase in diuresis up to 600 ml, and then the polyuria develops (2-3 L and even 10 L of urine per day). A threat to pay attention to in this period of time, is the possibility that dehydration may develop.
(b) Zimnitskiy’s test — hyposthenuria, isosthenuria.
(c) Metabolism of protein and electrolytes of blood — at the beginning of the stage of polyuria there can be even some increase of their amount, which strengthens the danger of lethal case. Such a period is named stage of early polyuria. Then — during the late polyuritic period — considerable excreation of urea, creatinine, electrolytes of blood and decrease of these parameters in blood take place (hypokaliemia, hypochloremia, hyponatremia, hypocalcaemia, hypomagnesemia, etc.).
(d) General blood analysis — anemia, the shift of leukocytic formula to the left.
Dangerous in this period is the probable development of infectious diseases on the background of the reduced immunity (pneumonia, myocarditis, pyelonephritis, etc.) which can also cause a lethal case at ARF.
4. The period of recovery, during which there is a step-by-step restoring of frame of kidneys and their functions, is the longest — it lasts till 2 years. The main signs of convalescence are: restoring of the concentration function of kidneys and disappearance of anemia.
Chronic renal failure
Chronic renal failure (CRF) develops as a result of the decrease iumber of operating nephrons and decrease in function of kidneys — maintaining of stable homeostasis in an organism.
Etiopathogenesis: the main reasons of CRF are: inherent anomalies of urinary system, and also pyelonephritis and glomerulonephritis of chronic course. As a result of severe diseases of kidneys there is disconnecting of one nephron, and as the process new and new ones are involving. The group of healthy nephrons is decreasing; and their function load is increasing. Which results in violation of their structure and function and also to their faster destruction.
|
Urea |
more than 10 mmol/L |
|
Creatinine |
more than 0,177 mmol/L |
|
Glomerular filtering |
less than 20 mL/min |
The progressing defeat of renal tissue appears in the form of CRF not at once. From the point of view of pathogenesis, depending on the percentage amount of the perished nephrons it is possible to divide the course CRF into three stages:
1st — 50% — at usual rules of inspection of the patient renal failure is not determined, as the operating part of nephrons fulfils the function of kidneys.
2nd — 75% — functionally compensated stage at the expense of 25% of operating nephrons; however there are different violations (polyuria, the excretion of considerable amount of electrolytes with urine, the decreasing of concentration ability of kidneys, the development of anemia).
3rd— 90% — the stage of decompensation, for which oligoanuria, acidosis, hyperazotemia and hyperhydratation, the violation of an amount of electrolytes in blood are characterized (dangerous hyperkaliemia, etc.) and also anemia and hypertension. Depending on the chacked pathogenic changes the appropriate clinical symptoms are divided into 2 stages: initial (polyuric) and terminal (oligoanuric). Gradually there is a transition of the first stage into second one which reduces life to 3-7 years.
Rather new effective ways of treatment of CRF are hemodialysis and kidney transplantation.
