The etiology and pathogenesis of pyelonephritis

In the origin and development of pyelonephritis important role played by the type and nature of the infection; the General condition of the organism, the degree of immunobiological reactivity; changes in kidney and urinary tract, promoting localization in them infection and the development of the inflammatory process; ways of infection in the kidneys.
In patients with pyelonephritis in the urine can detect pure culture of E. coli, mixed flora, mainly containing E. coli, Staphylococcus, Proteus and enterococci, are less streptococci and staphylococci.
A significant role in the emergence and development Ii. has reduced resistance to infection in the result of fatigue, previous severe systemic infections, hypovitaminosis, excessive cooling, circulatory disorders, and so on, and the massiveness of infection. In addition, of great importance in the development of Peterhof are functional and organic changes in the urinary tract, resulting in violation of patency them anywhere, since the level of nephron to the urethra. The penetration of microbes in the kidney, and the subsequent allocation of them do not always cause pyelonephritis; often it is limited to bacteriuria. Only under particularly unfavourable conditions (violation of the passage of urine prior to the defeat of kidneys of a process, and so on) bacteria are vital activity, and then occurs in the kidney inflammation. Violation of the cross urinary tract infections most often associated with the presence of a stone, narrowing, bend or compression of the urethra and periarteritis, adenoma of prostate gland, etc.
There are four ways of infection in the kidney and renal pelvis: hematogenous, lymphogenous, on the wall of the urethra and its level at vesicoureteral-reflux. Hematogenous pyelonephritis is a secondary source of infection penetrated into the kidney from a primary tumor, most commonly found in the urogenital system. If the infection is logged in the kidney from the hearth, located far from the kidneys and urinary tract, the cause of it are usually gram-positive cocci. Infection of the urinary tract and genital organs easily penetrates through the venous bed through the lymph vessels in the General circulation, and then entered into the kidney. Of great importance for the spread of infection from the renal pelvis into the interstitial tissue of the kidney and its vessels, mainly in Vienna, have pelvis-kidney reflux.
Lymphogenous way of infection of the bladder and the urinary tract, as well as from the intestines, little reliable. It is proved that the lymphatic vessels of the kidneys are collectors only for removing infections of the kidneys.
In humans, as in urothelia, and in their own shell and into the muscle layer of the ureter of the lymphatic vessels not. The infection spreads interstitial tissue cracks in the subepithelial and the muscle layer of the ureter, and adventitia the last layer.
There is also the upward way, where infection penetrates into the kidney on the column of liquid in the ureter, as the moving microorganisms can climb up the urine with broken passage.