One of the most common kidney diseases is pyelonephritis. The pathogenesis of this process is associated with inflammatory and degenerative changes in the tissues of the organ. With inadequate treatment, this disease leads to the formation of multiple ulcers. So, what is this pathological process, what are the causes of pyelonephritis, the pathogenesis and treatment of this disease? Let's try to consider in this article.
What is this disease?
It refers to non-specific infectious and inflammatory pathologies, during which the pyelocaliceal system is affected, as well as the interstitial tissue of the kidney parenchyma. Pyelonephritis is one of the often diagnosed diseases of the genitourinary system in men, women and children. However, according to WHO statistics, women of young and middle age are most affected by this disease. They suffer from symptoms of pyelonephritis (the pathogenesis of which is more often infectious) almost five times more often than men.
Modern medicine divides this disease into primary (non-obstructive) or secondary (obstructive, developing against the background of impaired urine outflow due to inflammation of the tissues and their compression) pyelonephritis. In this case, acute and chronic forms are distinguished by the clinical course of infectious and inflammatory pathology.
Etiology and pathogenesis of pyelonephritis
This pathological phenomenon can be triggered by any endogenous or exogenous microorganisms that have penetrated the renal tissue. These are usually gram-negative bacteria. The most common pathogenesis is with a clinic of pyelonephritis caused by Escherichia coli (more than 50% of cases). With prolonged treatment of the disease with the use of antibiotic therapy schemes, the addition of candida infection is possible.
Pathogens can enter the kidney tissue in three ways:
- In the presence of foci of inflammation in the internal organs, pathogenic microflora can penetrate the kidneys through the circulatory system (hematogenous pathway). This is one of the most common ways to infect the pelvic organs as a whole.
- In the presence of vesicoureteral-pelvis reflux (reverse urine flow resulting from certain physiological processes), an infection called ascending (urinogenous) can occur.
- The causes of the pathogenesis of pyelonephritis can be ascending infection along the subepithelial spaces of the ureter wall.
Phenomena of ascending urinogenous processes are possible only in the presence of infected urine in the urinary bladder that enters the ureter first into the pyelocaliceal system, and then into the kidney parenchyma. This process is possible only in the presence of a fornical (reflux of the calyx arch) or tubular (reverse urine reflux from the renal pelvis to the parenchyma, more precisely, to the renal tubules) of the reflux type.
In the process of ascending urinogenic infection, hematogenous infection is also possible. This happens when microbes penetrate the kidney tissue due to pyelovenous or pyelolymphatic reflux.
The pathogenesis of acute pyelonephritis can be triggered by local changes in the kidneys and upper urinary tract. Typically, these phenomena are associated with impaired passage of urine, for example, due to the destruction of the stone, the structural features of the ureter and other reasons. The source of pyelonephritis can be a violation of the outflow of urine caused by phimosis or inflammation of the prostate gland. The etiology and pathogenesis of chronic pyelonephritis in this case is accompanied by hemodynamic changes in the interstitial tissue, which helps to create optimal conditions for the life of pathogenic microorganisms.
The dynamics of the development of the disease is greatly affected by the general condition of the body. Factors that have a negative effect on the condition of the kidneys are:
- poor or unbalanced nutrition;
- lack of vitamins and vital trace elements;
- dehydration of the body;
- hypothermia;
- frequent somatic diseases;
- physical overload;
- diseases of the endocrine and cardiovascular systems, as well as liver disease.
Such conditions reduce the body's resistance and make it susceptible to any infections.
Stages of the disease: causes and symptoms
The pathogenesis of pyelonephritis is determined by the stage of development of the disease, the presence of complications, as well as a combination of the clinical manifestations of the infectious process and local symptoms. The stages of development of this disease correspond to morphological changes occurring in the kidney.
The initial stage of the disease is a serious process, the duration of which varies from 6 to 36 hours. Against the background of secondary pathogenesis of pyelonephritis in children and adults, accompanied by general weakness of the body and ailments, symptoms such as:
- fever with a further increase in body temperature to 40 ° C and above;
- sometimes there is colic followed by chills;
- increased sweating;
- headaches, nausea, sometimes vomiting;
- in rare cases, patients notice the appearance of diarrhea, dry mouth and tachycardia attacks.
After a decrease in temperature, one feels better. However, apparent relief is an imaginary state. If the prerequisites for violations in the body are not eliminated, then a few hours after such an attack, severe pain in the lower back will appear again, and the attack will recur.
With non-obstructive (primary) pyelonephritis, local symptoms may be absent.
The subsequent stages of the disease are characterized by purulent, destructive changes that occur in the following sequence:
- Apostematous pyelonephritis, in which small (1-2 mm) multiple abscesses appear on the surface and in the cortical substance of the kidney.
- Organ carbuncle, arising either from the fusion of purulent formations with apostematic pyelonephritis, or due to the ingress of a microbial embolus into the final arterial vessel of the organ, which is manifested by a combination of ischemic, necrotic and purulent-inflammatory process.
- Kidney abscess occurs as a result of purulent fusion of tissues. The contents of a bursting abscess can penetrate into the umbilical fiber, as a result of which the development of purulent paranephritis or even retroperitoneal phlegmon (inflammation that does not have clear boundaries) is likely.
- Purulent paranephritis.
With such processes, pain in the lumbar region passes by bouts. In a similar case of the pathogenesis of acute pyelonephritis, a painful organ can be felt, because muscle tension from the affected kidney occurs.
As the body is intoxicated, the patient is dehydrated and pallor of the skin.
What happens in the body in the acute course of the disease
In the diagnosis and treatment of acute pyelonephritis (the clinic of the etiology and pathogenesis of which is manifested in the appearance of a large number of pustules caused by infections), the course of this inflammatory disease is aggravated. However, according to many clinical experts, there are often some difficulties in determining the true culprit of a patient's well-being, leading to diagnostic errors.
In the acute course of the disease, the kidney undergoes some changes: it becomes larger, and its fibrous dense cover (capsule) is compacted. When it is opened, the bean-shaped organ bleeds and, as a rule, perinephritis is observed. On the incision of the affected kidney there are wedge-shaped yellowish areas, and upon microscopic examination in the interstitial tissue, multiple perivascular infiltrates are found with a tendency to the formation of abscesses.
An infection present in the interstitial tissue enters the lumen of the tubules. Many small, millet-like painful foci (a characteristic feature of apostematic nephritis) are formed in the renal glomeruli. At the same time, on the basis of the presence and circulation of a pathogenic agent in the blood or lymph, pustules appear around the tubules of the kidney.
In addition, in the pathogenesis of acute pyelonephritis there is the formation in the brain of the kidney of pustules and purulent gray-yellow stripes, extending up to the papillae. With a more thorough study, the accumulation of leukocytes is detected both in the direct tubules and in the surrounding tissues. Blood supply disturbances in the papilla can cause necrosis and lead to the pathogenesis of chronic pyelonephritis, while numerous small abscesses (apostems) can merge and form one abscess.
Pathological changes in acute forms of pyelonephritis often occur against the background of the appearance of numerous pustules located throughout the area of the affected organ. Nevertheless, the highest concentration of apostem is found either in the cortical layer, or in any one zone of the kidney, where they are concentrated in the carbuncle.
When several apostems merge or the carbuncle melts during acute pathogenesis of pyelonephritis, diagnostics performed using laboratory and instrumental studies determine the kidney abscess. In case of blood supply disorders caused by inflammatory edema or vascular thrombosis, necrotic papillitis occurs.
An acute course of this disease can occur at any age, regardless of the patient’s gender and ethnicity, but non-obstructive (primary) processes are most often observed in the pathogenesis of pyelonephritis in children and women under 40 years of age.
The clinical manifestations of this disease in the acute course are characterized by a combination of general and local symptoms. Common symptoms include:
- fever and severe chills;
- increased sweating;
- changes in the composition of the blood;
- jumps in blood pressure;
- signs of intoxication.
Local manifestations are such as:
- lower back pain (provoked by examination or spontaneous);
- muscle tone in the hypochondrium and lower back;
- discoloration and composition of urine;
- rapid and sometimes painful urination.
Symptoms of an acute form of the inflammatory process
Full diagnosis and treatment of the clinic of the pathogenesis and etiology of acute pyelonephritis are often vital steps for the patient. The main manifestations of this pathological process are, first of all, a sharp increase in body temperature to 39-40 ° C, the appearance of weakness, chills, headaches, increased sweating and the main signs of intoxication (dizziness, nausea, vomiting, sometimes diarrhea). At the same time, lower back pain appears, localized, as a rule, on the one hand. In this case, pain can be dull, aching, or acute.
Often, the mechanism of nucleation and development of pyelonephritis (pathogenesis) is preceded by urolithiasis. In this case, acute renal colic is observed before the onset of the onset of the disease, but without impaired urination.
Sometimes, at the initial stages of the development of the pathogenesis of pyelonephritis in women, men and children, signs of a serious infectious process without local manifestations are traced. In the first hours of the onset of the disease, severe chills are usually observed, accompanied by febrile conditions with high fever, headache and aching throughout the body. Along with a decrease in temperature, imaginary relief comes, but the patient has rapid breathing and dry mouth.
In the process of manifestation of the general symptoms of pyelonephritis, local signs are gradually added: pains of varying intensity in the lower back, groin or upper abdomen. The appearance of increased pain is characteristic of cases of the transition of inflammation to the capsule of the kidney or perinephric fiber. Periodic temperature increases usually indicate the development of numerous pustular foci in the organ.
A few days after the onset of infectious etiology and pathogenesis of pyelonephritis in children and adults, the pain syndrome is localized in the area of the affected organ. At the same time, there is an increase in pain at night, especially when lying on your back. Unpleasant sensations can intensify with deep sighs or coughing.
During the examination, palpation noted pain, accompanied by a tonus of the muscles of the back and abdomen. Severe pain is observed when pressing with fingers at certain points:
- from the back at the intersection of the lower ribs with long lumbar muscles;
- from the abdomen in the so-called upper ureteric point, located three fingers to the left or right of the navel.
Often, patients experience scoliosis in the direction of the affected kidney.
Chronic pyelonephritis: symptoms
As a rule, the etiology and pathogenesis of chronic pyelonephritis are consequences of an untreated disease that proceeds in an acute form. This happens in cases where the inflammatory process in the kidney was removed, but the pathogen remained. Chronic pyelonephritis also occurs in situations where it was not possible to normalize the outflow of urine from the body.
The disease can constantly bother with dull aching pains in the lumbar region, especially in the autumn-spring period. In addition, the ailment can periodically worsen, and then the patient experiences all the signs of the acute course of this pathology.
Modern medicine distinguishes between local and local symptoms of pyelonephritis, which proceeds in a chronic form. Local symptoms include periodically appearing mild pain in the lumbar region, usually unilateral. They rarely occur with active movement and are more often observed at rest.
In the primary course of the pathogenesis of chronic pyelonephritis, the pain syndrome never takes on the character of renal colic and does not affect other areas. In patients with a secondary form of the disease, the symptoms are more pronounced, since they are complications of a number of diseases that lead to a violation of the outflow of urine from the kidneys. It can be urolithiasis, benign growths of the prostate gland, uterine fibroids, kidney prolapse and other pathologies.
In a significant number of patients, especially in the treatment of the pathogenesis of pyelonephritis in women, the inflammatory process occurs against the background of long-term therapy of chronic cystitis with frequent exacerbations. Therefore, patients with a chronic form of pyelonephritis often report urination disorders associated with inflammation of the bladder.
The general symptoms of chronic pyelonephritis are divided into early and late.
Early symptoms are characteristic of patients with unilateral or bilateral pyelonephritis, not accompanied by impaired renal function. In this case, it is observed:
- fast fatiguability;
- periodically appearing weakness;
- loss of appetite;
- low-grade body temperature.
The culprit of such manifestations is venous congestion in the kidneys, while most people have an increase in blood pressure.
Late symptoms include phenomena such as:
- dry mouth
- discomfort in the adrenal region;
- heartburn and belching;
- psychological passivity;
- the appearance of puffiness;
- pallor and dry skin.
Such symptoms may serve as some manifestations of chronic renal failure. Therefore, the treatment and prevention of the clinic of the pathogenesis of chronic pyelonephritis is a prerequisite for the normal functioning of the patient.
During pregnancy
According to medical statistics, various inflammatory pathologies of the kidneys occur in approximately 10% of pregnant women. The fact is that in all systems and organs of the female body during this period, numerous changes occur. So, under the influence of a hormone that supports pregnancy (progesterone), the smooth muscles of the ureters, bladder and urethra are relaxed. Often this allows the pathogenic environment to enter the urinary tract.
In addition, the fetus growing during pregnancy exerts significant pressure on the kidneys and bladder, which leads to disruption of blood circulation in the tissues of these organs and contributes to urinary retention. Often this becomes the determining factor in the occurrence of the pathogenesis of pyelonephritis in pregnant women. It is worth adding here the weakening of the protective functions of the immune system, since the main forces of the female body during this period are thrown to ensure the normal course of pregnancy.
Problems in diagnosing pyelonephritis
Recently, there has been a tendency to a latent course of this disease.This significantly complicates the diagnosis of pyelonephritis not only in chronic but also in acute form. Therefore, an ailment is accidentally detected only during examination for other diseases or already in the late stages of pathogenesis. The etiology of pyelonephritis in children and adults can last for years.
When diagnosing this pathological process, it should be remembered that:
- Pyelonephritis is much more common in young women.
- , , .
- , - (), ( ) ( , ).
. , , – , , .
Another early sign of the disease can be nocturia, noted for several years and not associated with the use of large amounts of fluid. Despite the fact that this symptom is not specific for pyelonephritis, nocturia may indicate a decrease in the concentration function of the kidneys.
Laboratory diagnosis of the disease
The prognosis of the pathogenesis of pyelonephritis can only be given by a qualified specialist after studying the results of a number of laboratory and instrumental analyzes and tests.
Laboratory research
Clinical urine tests are one of the main stages of diagnosis. Pyelonephritis is characterized by the identification of an increase in the number of leukocytes, however, the obtained data should always be compared with the patient's complaints and a medical history. So, for example, asymptomatic manifestations of leukocyturia in women (up to 60 or more leukocytes) require the exclusion of gynecological pathologies. And when combining minimal leukocyturia with an increase in body temperature, it is necessary to be guided by the data of anamnestic, clinical, laboratory and instrumental examination.
In the prevention and prognosis of the pathogenesis of pyelonephritis, urine pH is particularly noteworthy. Normally, in the presence of urinary infection, the acid reaction may change to sharply alkaline. However, it can also be observed, for example, with uremia or pregnancy.
Urine culture: theoretically, this method can give an idea of the pathogen and help to select adequate treatment regimens. However, in real practice this does not always happen, therefore, it is impossible to rely on the results obtained using this method.
Instrumental diagnostics
This technique usually involves the use of ultrasound, x-ray, radionuclide equipment.
During chromocystoscopy and excretory urography, signs of primary acute pyelonephritis are expressed by a decrease in the function of the affected kidney, as well as a slowdown in the excretion of colored or concentrated urine from the affected areas. With the help of excretory urograms in the early stages of the onset of chronic pyelonephritis, hypertension and calyx hyperkinesia can be detected, which in the later stages of the disease are replaced by hypotension.
With the help of ultrasound (ultrasound) during the development of pyelonephritis, it is possible to detect enlargement of the renal pelvis, coarsening of the contours of the cups, heterogeneity of the structure of the parenchyma with areas of scarring, and also mobility of the kidneys. This is the most popular method for determining pathological processes in an organ.
This technique allows you to detect signs of delayed manifestations of the disease. Among them, deformation and resizing of the kidney or a change in the thickness of the parenchyma can be noted. However, these indicators may also indicate the development of other nephropathies. In addition, ultrasound examinations of the kidneys reveal the pathologies associated with pyelonephritis: urolithiasis, obstructive uropathy, vesicoureteral reflux (PMR), polycystic kidney disease and other conditions preceding the onset of a purulent-inflammatory process.
It is possible to identify the position, shape of the kidneys and the presence of stones in the urinary system using survey urography techniques.
Computed tomography is also often used to diagnose pyelonephritis, however, this technique does not give special advantages over ultrasound, therefore it is mainly used to determine tumor processes. In this case, SKT and MSCT are considered the most informative methods for studying kidney disease, providing three-dimensional reconstruction of the organ image and virtual endoscopy with size detail and structural density of the neoplasms.
Radionuclide methods for diagnosing pyelonephritis allow you to identify a functioning parenchyma, delimiting the areas of scarring, which allows to predict the pathogenesis of the disease.
X-ray examination
The use of x-ray methods allows you to visualize the urinary tract and identify signs of obstructive uropathy and urinary flow. This method is used to detect chronic pyelonephritis by detecting coarsening and deformities of the kidney contours, thinning of the parenchyma, dilatation and hypotension of the pelvis, smoothing of the papillae and narrowing of the necks of the cups
Treatment and prognosis
Uncomplicated acute pyelonephritis can be treated with conservative methods in a hospital setting. For the most rapid relief of the inflammatory process and reduce the risk of the transition of the pathological process into a purulent-destructive form, various antibacterial therapy regimens are used. In the acute course of the disease, detoxification therapy is necessarily carried out and immunity is adjusted.
In the initial stages of treatment of secondary pyelonephritis in acute form, it is necessary to restore normal outflow of urine. For this, catheterization of the ureter is most often performed, and in advanced cases, pyelo- or nephrostomy is superimposed.
With febrile syndromes, a diet with a low intake of protein foods is prescribed. After stabilization of the patient’s body temperature, they are transferred to a complete diet with a high fluid content.
The treatment of chronic pyelonephritis occurs according to the same schemes as the treatment of an acute pathological process, but here the recovery period is longer and more laborious. Therapeutic measures in this case should include:
- identification and elimination of factors that could provoke difficulty in the outflow of urine or lead to impaired renal blood flow;
- taking antibiotics;
- correction of immunity.
Treatment and prevention of the pathogenesis of pyelonephritis in a chronic form requires a long systematic therapy and a full recovery process. The treatment started in the hospital should be continued on an outpatient basis. As additional methods, some recipes of traditional medicine and herbal medicine can be used, however, it is necessary to decide on the advisability of their use with a treating specialist. Patients suffering from manifestations of this pathological process, during the period of remission of the disease, it is recommended to undergo spa treatment.