Acute pyelonephritis

Although acute pyelonephritis is defined as inflammation of the kidney and renal pelvis, this diagnosis is clinical. The term "urinary tract infection" is used in cases where the infection is certainly present, but there are no obvious signs of direct kidney damage. The term "bacteriuria" is used to indicate that bacteria are not only constantly present in the urinary tract, but also actively multiply.

[1], [2], [3], [4]

Causes of the acute pyelonephritis

Acute pyelonephritis is an acute bacterial infection, manifested by inflammation of the pelvis and kidney parenchyma. Most often, infections of the urinary tract are caused by bacteria that live in the large intestine. 80 to 90% of primary urinary tract infections cause Escherichia coli, which is present in large amounts in feces.

Strains of Escherichia coli isolated during bacteriological examination of urine are also found on the skin around the external opening of the urethra, in the vagina, in the rectum. Not all strains of E. Coli possess virulence factors. Of the numerous strains of Escherichia coli (over 150), only some are uropathogenic, in particular serotypes 01.02.04.06,07,075.0150.

Other frequent Gram-negative pathogens (Klebsiella pneumoniae, Enterobacter aerogenes / agglomerans, Proteus spp.) And Gram-positive (Enterococcus faecalis, Staphylococcus saprophyticus) bacteria of the Enterobacteriaceae family are also referred to as frequent infectious agents of urinary infection. Anaerobic bacteria present in the intestines in much larger amounts rarely infect the kidneys. It should also be noted that chlamydia and ureaplasma do not act as causative agents of acute pyelonephritis. Diseases such as atrophic vaginitis, sexually transmitted diseases (caused by chlamydia, gonococcus, herpesvirus infection), as well as candidal and trichomonas vaginitis, which also causes increased urination, are not considered infections of the urinary tract.

Proteus mirabilis plays an important role among pathogenic pathogens. It produces urease, which splits urea into carbon dioxide and ammonia. As a result, urine is alkalinized, and tripolphosphate stones are formed. Deposited bacteria in them are protected from the action of antibiotics. Reproduction of Proteus mirabilis promotes further alkalinization of urine, precipitation of tripolphosphate crystals and the formation of large coral stones.

To ureazoprodutsiruyuschim microorganisms also include:

• Ureaplasma urealyticum:
• Proteus spp.
• Staphylococcus aureus;
• Klebsiella spp.
• Pseudomonas spp.
• E. Coli.

Mixed urinary tract infections, when several pathogens are excreted from the urine, with a primary acute pyelonephritis are rare. However, with complicated acute pyelonephritis caused by hospital (nosocomial) strains of microorganisms, especially in patients with various catheters and drainages, stones in the urinary tract, after intestinal plastics of the bladder, a mixed infection is often given.

[5], [6]

Pathogenesis

The development of acute pyelonephritis bacterial, of course, begins with the introduction of bacteria into the urinary tract. Further, the process proceeds depending on the factors inherent in the micro- and macroorganism, and their interactions. The state of general and local defense mechanisms determines susceptibility to urinary tract infections. The corresponding anatomical lesion in the kidney consists of a significant number of polymorphonuclear leukocytes in the interstitial space of the kidney and the lumen of the tubules, sometimes with sufficient density to form an abscess. Abscesses can be multifocal, suggesting a metastatic spread from the bloodstream (bacteremia), or, more often, appear as a focal infection diverging in the renal papilla within the kidney segment, forming a wedge-shaped lesion that extends to the cortex of the kidneys (ascending infection pathway).

If there is a pronounced acute pyelonephritis (acute lobar nephronia) on intravenous urograms, computer tomograms or ultrasound scans, one can see a localized, non-fluid protrusion that involves one kidney or more in the process. Defeat can be difficult to distinguish from a tumor or abscess.

There are 3 ways of penetrating pathogenic microorganisms into the urinary tract:

• ascending (colonization by bacteria of the intestinal group of the external opening of the urethra, from where they enter the urethra and bladder);
• hematogenous (for example, screening the pathogen in the kidneys with the formation of an abscess with staphylococcal bacteremia;
• contact (the spread of microorganisms from neighboring organs, for example, with a vesicourous fistula, the formation of a bladder from the gut segment).

Through the glomerular filtration bacteria in the urinary tract usually do not penetrate.

The most common way is ascending. On the short female urethra, the uropathogenic microorganisms that populate its outer opening easily penetrate the bladder, especially during intercourse, so women who have an active sex life get urinary tract infections more often. In men, the risk of ascending infections is less, due to the longer length of the urethra, the remoteness of its outer opening from the anus and the antimicrobial properties of the secretion of the prostate. In infants with uncircumcised foreskin, in young men who have an active sex life, as well as in older men, the accumulation of bacteria in the folds of the foreskin, non-compliance with hygiene and fecal incontinence contribute to the colonization of the urinary tract by uropathogenic bacteria. Catheterization of the bladder and other endoscopic interventions on the urinary tract increase the risk of their infection in people of both sexes. After a single catheterization, the risk is 1-4%; with continuous catheterization and the use of open drainage systems, infection of urine and urinary tract inevitably occurs in a few days.

Microorganisms, including mycobacteria and fungi, can enter the kidneys, bladder and prostate by hematogenous way from the primary focus of infection in other organs (for example, kidney abscess and paranephritis caused by staphylococci or pyogenic streptococcus). The direct spread of infection from the intestine to the bladder occurs in the bladderworm fistula (as a complication of diverticulitis, colon cancer, Crohn's disease), while a large number of different types of enterobacteria (mixed infections), gas (pneumaturia) and feces are often found in the urine.

Till now in the domestic literature it is accepted to consider as the main and almost the only way of infection of the kidney - hematogenous. Such an idea was artificially created from the time of Moskalev and other experimenters who injected the animal with an intravenous pathogen, while creating a supra-vocal obstruction of the ureter, through its dressing. However, even the classics of urology at the beginning of the last century, the topical forms of acute infectious and inflammatory process in the kidney were clearly divided into "pyelitis, acute pyelonephritis and purulent nephritis." Most authors of modern foreign literature, as well as WHO experts in their latest classification (ICD-10), consider the urinogenic pathway of kidney infection to be the main one.

The ascending (urinogenic) pathway of infection has been confirmed in the experimental works of a large number of domestic and foreign researchers. It was shown that bacteria (proteus, E. Coli and other microorganisms of the Enterobacteriaceae family) introduced into the bladder, multiply rapidly and spread up the ureter, reaching the pelvis. The fact of the ascending process in the lumen of the ureter was proved by fluorescent microscopy on the bacteria Teplitz and Zangwill. From the pelvis, the microorganisms multiply reach the brain substance with spreading towards the cortex of the kidney.

The introduction into the bloodstream of cultures of microorganisms has convincingly shown that microorganisms do not penetrate the bloodstream into urine through intact kidneys, i.e. The generally accepted idea among doctors today is that the carious tooth can be the cause of acute pyelonephritis, can not withstand any criticism, and for this reason, and for various pathogens of acute pyelonephritis and caries.

The predominantly upward pathway of infection of the urinary tract and kidney also corresponds to the clinical data: the high incidence of unilateral uncomplicated acute pyelonephritis in women, the association with cystitis, the presence of P-fimbria in E. Coli, by which it adheres to the urothelial cell, and the genetic identity of bacteria isolated from women with primary acute pyelonephritis from urine, feces and vagina.

Various topical forms of acute inflammation of the kidney are also characterized by different ways of infection: for the pierelitis, the ascending (urinogenic) pathway of infection is common, for pyelonephritis - urinogenic and urinogenous-hematogenous, for purulent nephritis - hematogenous.

The hematogenous pathway of infection or renin infection can complicate the course of uncomplicated urinogenic acute pyelonephritis in the development of bacteremia, when the lesion itself in the body is the affected kidney itself. Data of the international multicentre PEP-study, with acute pyelonephritis, diagnose urosepsis in different countries is set at 24%, and according to researchers, only 4%. Obviously, Ukraine underestimates the state of severity of purulent acute pyelonephritis, complicated by bacteremia, which foreign authors interpret as urosepsis.

The risk factors for kidney abscess include urinary tract infection in history, urolithiasis, vesicoureteral reflux, neurogenic bladder dysfunction, diabetes mellitus and pregnancy, as well as the properties of the microorganisms themselves that produce and acquire pathogenicity genes, high virulence genes and resistance to antibacterial drugs. The localization of the abscess depends on the path of infection. When the hematogenous spread affects the cortical substance of the kidney, and with the ascending, as a rule, the cerebral and cortical substance.

The course of acute pyelonephritis and the risk of complications are determined by the primary or secondary nature of the infection. Primary (uncomplicated) acute pyelonephritis responds well to antibacterial therapy and does not lead to damage to the kidney. Severe course of primary acute pyelonephritis can lead to wrinkling of the cortex, but the remote effect of this complication on kidney function is unknown. With secondary infections of the kidneys severe lesions of the renal parenchyma, abscess and paranephritis are possible.

[7], [8], [9], [10], [11]

Symptoms of the acute pyelonephritis

Symptoms of acute pyelonephritis can vary from sepsis caused by gram-negative bacteria, to signs of cystitis with unexpressed pain in the lumbar region.

Symptoms of acute pyelonephritis are most often manifested in mild local signs of inflammation. The condition of the patient is of medium severity or severe. The main symptoms of acute pyelonephritis are: malaise, general weakness, fever to 39-40 ° C, chills, sweating, pain in the side or in the lumbar region, nausea, vomiting, headache.

Often observed symptoms of cystitis. The pain is typical for palpation and effleurage in the rib and vertebral corner on the side of the lesion, reddening of the face, tachycardia. Patients with uncomplicated acute pyelonephritis, as a rule, have normal blood pressure. In patients with acute pyelonephritis, diabetes mellitus, structural or neurological anomalies can be accompanied by hypertension. In 10-15% of patients, micro- or macrohematuria is possible. In severe cases, urosepsis develops, caused by gram-negative bacteria, necrosis of the renal papillae, acute renal failure with oliguria or anuria, kidney abscess, paranephritis. In 20% of patients, bacteremia is detected.

In secondary complicated acute pyelonephritis, including in hospitalized patients and patients with persistent urinary catheters, the clinical symptoms of acute pyelonephritis range from asymptomatic bacteriuria to severe urosepsis and infectious-toxic shock. Deterioration of the condition can begin with a sharp increase in pain in the lumbar region or an attack of renal colic due to a violation of the outflow of urine from the kidney of the kidney.

Characterized by hectic fever, when hyperthermia to 39-40 ° C is replaced by a critical drop in body temperature to subfebrile digits with torrential sweat and a gradual decrease in the intensity of pain, until complete disappearance. However, if the obstruction to the outflow of urine is not eliminated, the patient's condition worsens again, pains in the kidney area increase and fever with chills reappears. The severity of the clinical picture of this urological disease varies depending on the age, sex, previous state of the kidneys and urinary tract, availability of hospitalizations to the present day, etc. In elderly and senile patients, in weakened patients, as well as in the presence of severe concomitant diseases against the background of the immunosuppressive state, the clinical manifestations of the disease are erased or perverted.

In children, the symptoms of acute pyelonephritis are manifested in the form of increased body temperature, the occurrence of vomiting, abdominal pain, and sometimes a stool. In infants and young children, the symptoms of acute pyelonephritis can be erased and represented only by excitability and fever. The mother may notice an unpleasant smell of urine and signs of stress during urination. The diagnosis is established if pus, white blood cells and bacteria are detected in the analysis of freshly released urine.

Pathogens of complicated urinary tract infections are more likely to be mixed more difficult to treat, more virulent and resistant to antibacterial drugs. If a hospitalized patient suddenly had signs of septic shock (especially after a catheterization of the bladder or endoscopic interventions on the urinary tract), even in the absence of symptoms of a urinary tract infection, urosepsis should be suspected. With complicated (secondary) infections of the urinary tract, the risk of urosepsis, necrosis of the renal papillae, abscess of the kidney and paranephritis is especially high.

[12], [13], [14], [15]

Diagnostics of the acute pyelonephritis

The diagnosis of uncomplicated (non-obstructive) acute pyelonephritis was confirmed by positive culture bacteriological examination of urine (microbial number - over 10 ⁴  cfu / ml) associated with pyuria. This clinical syndrome is actually found only in women, most often between the ages of 18 and 40. Approximately 50% of patients with lumbar pain and / or fever have bacteriuria from the lower urinary tract. Conversely, often in patients with or without symptoms of cystitis, the source of bacteriuria may be the upper urinary tract. Approximately 75% of patients with uncomplicated acute pyelonephritis have a history of infection of the lower urinary tract.

[16], [17], [18], [19], [20]

Clinical diagnosis of acute pyelonephritis

Diagnosis of acute pyelonephritis is important, due to the severity of the patient's condition, revealing obstruction of the urinary tract. Sometimes it is difficult to determine the stage of the infectious inflammatory process in the kidney, which does not always correspond to the clinical picture of the disease. Although infections of the lower and upper urinary tract are differentiated according to clinical data, it is impossible to pinpoint the localization of infection on them. Even such signs as fever and pain in the side are not strictly diagnostic for acute pyelonephritis, since they are found in the infection of the lower urinary tract (cystitis) and vice versa. Approximately 75% of patients with acute pyelonephritis had previous history of infection of the lower urinary tract.

In physical examination, muscle tension is often detected with deep palpation in the rib-vertebral corner. Acute pyelonephritis can simulate symptoms of gastrointestinal lesions with abdominal pain, nausea, vomiting and diarrhea. Asymptomatic progression of acute pyelonephritis in its chronic course in the absence of obvious symptoms can occur in patients with immune deficiency.

[21], [22], [23], [24]

Laboratory diagnostics of acute pyelonephritis

Diagnosis of acute pyelonephritis is based on a general analysis of urine and a bacteriological study of urine on the microflora and sensitivity to antibacterial drugs. If suspicion of acute pyelonephritis is necessary, in addition to clinical symptoms, use methods to clarify the location of infection.

In a general blood test, leukocytosis is usually detected with a shift of the leukocyte formula to the left. The concentration of urea and creatinine in the blood serum is usually within the normal range. Patients with a long, complicated infection can have azotemia and anemia if both kidneys are involved in the inflammatory process. Proteinuria is also possible, both in uncomplicated and with complicated acute pyelonephritis. Reducing the concentration ability of the kidneys is the most constant sign of acute pyelonephritis.

Proper collection of urine for research is very important. Avoid urine contamination with the microflora of the urethra only with suprapubic urinary bladder puncture. In this way, urine can be obtained from infants and patients with spinal cord injury. In other cases, it is resorted to when it is impossible to obtain urine in other ways.

For the study, take an average portion of urine with an independent urination. In men, the foreskin is removed first (in uncircumcised) and the penile head is washed with soap and water. The first 10 ml of urine - flushed from the urethra, then - urine from the bladder. In women, the probability of contamination is much higher.

In urinalysis, leukocyturia and bacteriuria are not detected in all patients with acute pyelonephritis. In the study of urine in patients with a predominantly cortical location of foci of infection (apostematous acute pyelonephritis, abscess of the kidney, perinephritis abscess) or with obstructive acute pyelonephritis (with blockage of urinary retention from the affected kidney), bacteriuria leukocyturia may not be present.

In urinalysis, erythrocytes may indicate the presence of necrotic papillitis. Stones in the urinary tract, an inflammatory process in the neck of the bladder, and so on.

When suspected of acute pyelonephritis, a bacteriological analysis of urine on the microflora and sensitivity to antibiotics is mandatory. It is considered to be a diagnostically significant microbial titer of 10 ⁴  CFU / ml for the diagnosis of uncomplicated acute pyelonephritis in women. In the culture of urine, the identification of microorganisms is only possible in a third of cases. In 20% of cases, the concentration of bacteria in the urine is below 10 ⁴  cfu / ml.

Patients are also carried out a bacteriological analysis of blood on the microflora (the result is positive in 15-20% of cases). The study of the culture of microorganisms in the blood, especially when a multitude of microorganisms are detected, more often indicates a paranal abscess.

Thus, quite often antibacterial treatment is prescribed empirically, i.e. Based on the knowledge of bacteriological monitoring data in the clinic (department), data on the resistance of pathogens, based on clinical studies known from the literature and own data.

Instrumental diagnosis of acute pyelonephritis

Diagnosis of acute pyelonephritis also includes radiation diagnostic methods: ultrasound scanning, X-ray and radionuclide methods. The choice of method, the sequence of application and the scope of the studies should be sufficient to establish a diagnosis, determine the stage of the process, its complications, identify the functional state and urodynamics of the affected and contralateral kidney. Among diagnostic methods, ultrasound scanning of the kidneys takes first place. However, if necessary, begin the study with chromoscystoscopy to detect obstruction of the urinary tract or an X-ray examination of the kidneys and urinary tract.

Ultrasound diagnosis of acute pyelonephritis

The ultrasound picture with acute pyelonephritis varies depending on the stage of the process and the presence or absence of urinary tract obstruction. Primary (non-obstructive) acute pyelonephritis in the initial period, in the phase of serous inflammation, can be accompanied by a normal ultrasound picture when examining the kidneys. In secondary (complicated, obstructive) acute pyelonephritis, only signs of urinary tract obstruction can be detected in this stage of inflammation: enlargement of the kidney size, expansion of its calyces and pelvis. As the infectious and inflammatory process progresses, the interstitial edema increases, the echogenicity of the kidney parenchyma increases, its cortical layer and pyramids are better differentiated. With apostematous nephritis, the ultrasound pattern can be the same as in the phase of serous inflammation. However, the mobility of the kidney is often decreasing or absent, sometimes the kidney borders lose clarity, the cortical and cerebral layers are differentiated, and formless structures with non-uniform echogenicity are sometimes revealed.

With the kidney carbuncle, it is possible to bulge its outer contour, the heterogeneity of the hypoechoic structures, the lack of differentiation between the cortical and cerebral layers. When the abscess is formed, hypoechoic structures are sometimes observed to observe the level of the fluid and the capsule of the abscess. With parainfluorescent outflow of the purulent process beyond the fibrous capsule of the kidney on the echogram, a picture of an inhomogeneous structure with a predominance of echo-negative components is seen. External contours of a kidney uneven, indistinct.

With various obstructions (stones, strictures, tumors, congenital obstructions, etc.) of the upper urinary tract, dilated cups, pelvis, and sometimes the upper third of the ureter are observed. In the presence of pus, inflammatory detritus, inhomogeneous and homogeneous echopositive structures appear in them. Ultrasonic monitoring is widely used for the dynamic observation of the development of acute pyelonephritis.

Radiographic diagnosis of acute pyelonephritis

In the past, excretory urography was mainly used. However, this study reveals changes in only 25-30% of patients. Only 8% of patients with uncomplicated acute pyelonephritis found anomalies that affected the tactics of management.

X-ray symptomatology with non-obstructive acute pyelonephritis at early stages (serous inflammation) is poorly expressed. Intravenous urography is not recommended for the first few days after the onset of acute pyelonephritis for the following reasons:

• the kidney is unable to concentrate the contrast medium;
• the dilated segment of the proximal ureter can be confused with ureteral obstruction;
• RVB can cause acute renal failure in a dehydrated patient.

Intravenous urography is not indicated as a routine examination in women with symptomatic urinary tract infection.

The function of the kidneys, urodynamics on excretory urograms can be within normal limits. Perhaps a small increase in the size of the contours of the kidney and limiting its mobility. However, if the process passes into the purulent phase with the formation of carbuncles or abscess, the development of parainfrit, the radiographic picture takes a characteristic change.

On the survey urograms, one can see an increase in the size of the kidney contours, the limitation or lack of mobility (on inhalation and exhalation), a halo of discharge around the kidney due to edematous fat, bulging of the kidney contours due to carbuncle or abscess, the presence of shadows of concrements, unclearness, smoothness contours of the large lumbar muscle, curvature of the spine due to rigidity of the lumbar muscles and sometimes displacement of the kidney. Excretory urography allows you to obtain important information about the function of the kidneys, urodynamics, X-ray anatomy of the kidneys and urinary tract. Due to inflammation and edema of the interstitial tissue, in 20% of patients, the increase in the kidney or its part is noted. In the nephrographic phase, striation of the cortical substance can be seen. Stagnation of urine in the tubules due to edema, and narrowing of the kidney vessels slows the excretion of contrast medium. When obstructing the urinary tract, the symptoms of blockade are revealed: "mute or white" kidney (nephrogram), the contours of the kidney are enlarged, its mobility is limited or absent. With partial obstruction of the urinary tract on excretory urograms after 30-60 min, one can see enlarged calyxes, pelvis, ureter to the level of obstruction. The delay of RVC in the enlarged cavities of the kidney can be observed for a long time.

With acute necrotic papillitis (with urinary tract obstruction or diabetes mellitus), it is possible to see the destruction of the papillae, the erosion of its contours, the deformation of the fornix arches, the penetration of the contrast substance into the parenchyma of the kidney by the type of tubular refluxes.

CT scan

CT along with ultrasound sonography is the most specific method of evaluation and localization of kidney abscess and perinephritic abscess, however, the method is costly. Often you can see on the scans a wedge-shaped dense area that disappears after several weeks of successful treatment. In acute pyelonephritis, arterioles narrow, causing ischemia of the renal parenchyma.

Areas of ischemia are detected with CT with contrast. On tomograms they look like single or multiple foci of reduced density. Diffuse kidney damage is also possible. In CT, the displacement of the kidney and fluid or gas in the perirenal space, associated with the perinephric abscess, are determined. At present, CT is a more sensitive method than ultrasound. It is indicated for patients with obstructive acute pyelonephritis, bacteremia, paraplegia, diabetes mellitus or a patient with hyperthermia who does not stop for several days with drug therapy.

Other X-ray methods for diagnosis of nuclear magnetic resonance imaging, angiographic methods for acute pyelonephritis - are rarely used and for special indications. They can be shown in differential diagnosis of late purulent manifestations or complications of carbuncles, abscesses, parainfritis, festering cysts with tumors and other diseases, if these methods do not allow an accurate diagnosis.

[25], [26], [27]

Radionuclide Diagnosis of Acute Pyelonephritis

These methods of research for emergency diagnosis of acute pyelonephritis are rarely used. They provide valuable information on the function, blood circulation of the kidneys and urodynamics, but at the stages of dynamic observation and detection of late complications.

Kidney scintigraphy has the same sensitivity as CT in the detection of ischemia on the background of acute pyelonephritis. The radiolabelled 11Tc, localized in the cells of the proximal tubules, in the cortical substance of the kidney, makes it possible to visualize the functioning renal parenchyma. Kidney scanning is particularly useful for determining kidney involvement in children and helps differentiate reflux-nephropathy from local acute pyelonephritis.

On renograms with primary non-obstructive acute pyelonephritis, the vascular and secretory segments are flattened and elongated 2-3 times, the excretion phase is weakly expressed or not traced. In the phase of suppurative inflammation due to circulatory disturbance, the contrast of the vascular segment is significantly reduced, the secretory segment is flattened and slowed, and the excretory segment is weakly expressed. With total defeat by purulent kidney process, one can get an obstructive curve line in the absence of obturation of the upper urinary tract. With secondary (obstructive) acute pyelonephritis on the renograms at all stages of inflammation, one can get an obstructive type of the curve, the vascular segment is low. The secretory is slowed down, and the excretory segment is absent on the side of the lesion.

Differential diagnosis

Sometimes a patient with acute pyelonephritis may complain of pain in the lower abdomen, rather than a characteristic pain in the side or in the kidney area. Acute pyelonephritis can be confused with acute cholecystitis, appendicitis or diverticulitis and the occasional presence of bacteriuria and pyuria. Appendicular, tubo-ovarian diverticular abscesses, adjacent to the ureter or bladder may be accompanied by pyuria. Pain from passing the stone through the ureter can simulate acute pyelonephritis, but the patient usually does not have fever or leukocytosis. In urine, red blood cells without bacteriuria or pyuria are often detected, unless, of course, it has a concomitant urinary tract infection.

Treatment of the acute pyelonephritis

Indications for hospitalization

In the absence of nausea, vomiting, dehydration and symptoms of sepsis (systemic generalized reaction of the body), treatment of acute pyelonephritis is performed on an outpatient basis, provided that the patient complies with the doctor's prescriptions. In other cases, patients with primary pyelitis and acute pyelonephritis (as well as pregnant ones) are hospitalized.

Drug treatment of acute pyelonephritis

For all forms of acute pyelonephritis, bed rest is indicated.

Antibacterial treatment of acute pyelonephritis is prescribed by an outpatient for a period of 2 weeks. The guidelines of the European urological association (2006) recommend the use of oral forms of fluoroquinolones for 7 days with acute pyelonephritis as the first line of therapy in regions with a persistent low incidence of E. Coli resistance to fluoroquinolones (<10%). If a gram positive microorganism is detected by microscopy of a Gram stain smear, therapy with inhibitor-protected aminopenicillin can be recommended.

In more severe cases of uncomplicated acute pyelonephritis, hospitalization of the patient and parenteral treatment of acute pyelonephritis with fluoroquinolones (cilrofloxacin or levofloxacin), third generation cephalosporins or inhibitor-protected amino / acylaminopenicillins, depending on the patient's condition, and taking into account local data on the susceptibility of the pathogen to antibiotics are shown. With the improvement of the patient's condition, it is possible to switch to the intake of fluoroquinolones to complete the 1-or 2-week course of treatment, respectively. In the regions with the observed increase in the resistance of E. Coli to fluoroquinolones, as well as in patients who have contraindications to it (for example, pregnancy, lactation, children's age), oral dosage forms of cephalosporins of II or III generations are recommended.

In the absence of symptoms of the disease, culture culture of urine after treatment is not shown; for subsequent follow-up, a routine urine test with a test strip is sufficient. In women with a relapse of symptoms of acute pyelonephritis within 2 weeks after treatment, it is necessary to conduct a repeated culture of urine with the determination of the sensitivity of the isolated pathogen to antibiotics and additional studies to exclude structural disorders of the urinary tract.

With a recurrent infection, antibiotic treatment of acute pyelonephritis continues until 6 weeks. If fever and pain in the lumbar region, lateral parts of the abdomen persist for more than 72 hours after the initiation of treatment of uncomplicated acute pyelonephritis, repeated bacteriological analyzes of urine and blood, as well as ultrasound and CT of the kidneys are indicated to exclude complicating factors: urinary tract obstruction, anatomical abnormalities, kidney abscess and paranephritis. After 2 weeks after treatment, the bacteriological analysis of urine is repeated. With an exacerbation of urinary tract infection on the background of urolithiasis, nephrosclerosis. Diabetes mellitus, necrosis of the renal papillae, a 6-week course of antibiotic therapy is usually necessary, although you can limit yourself to a 2-week course and continue it only if the infection recurs.

All pregnant women with acute pyelonephritis are hospitalized and parenteral administration of antibiotics (inhibitor-protected beta-lactams, cephalosporins, aminoglycosides) is used for several days prior to normalization of body temperature. Subsequently, you can go to the reception of antibiotics inside. Duration of treatment 2 weeks. After receiving the results of bacteriological analysis of urine, the treatment is corrected.

Fluoroquinolones are contraindicated in pregnancy. It should be remembered that the use of sulfamethoxazole / trimethoprim in urinary tract infection and in acute pyelonephritis is not recommended because of the high incidence of resistant strains of microorganisms - pathogens of urinary infection (over 20-30%). In pregnant women, sulfonamides disrupt the binding of bilirubin to albumin and can provoke hyperbilirubinemia in newborns. Gentamicin should be administered with caution because of the risk of damage to the pre-cochlear nerve in the fetus.

Proper treatment of acute pyelonephritis leads to a complete cure, without leaving consequences. In children, when the formation of the kidney is not yet complete, acute pyelonephritis can lead to nephrosclerosis and kidney failure. The most dangerous complications of acute pyelonephritis are sepsis and an infectious-toxic shock. It is possible to form an abscess of the kidney, in which it is necessary to drain it.

When choosing an antibacterial drug for the empirical therapy of clinically expressed complicated, secondary acute pyelonephritis, a relatively large number of possible causative agents and the severity of the disease should be taken into account. Hospitalized patients with acute pyelonephritis and sepsis are first empirically prescribed broad-spectrum antibiotics active against Pseudomonas aeruginosa, the Enterobacteriaceae family, Enterococcus spp. (ticarcillin / clavulanate or amoxicillin / clavulanate + gentamicin or amikacin; third generation cephalosporins, aztreonam, ciprofloxacin, levofloxacin or carbapenems). After receiving a bacteriological analysis of urine and blood, therapy is adjusted depending on the results.

With secondary, complicated acute pyelonephritis, treatment is continued up to 2-3 weeks, depending on the clinical picture of the disease. After 1-2 weeks after the end of therapy, a bacteriological analysis of the urine is repeated. With clinically expressed recurrent infection, a longer antibiotic therapy is prescribed - up to 6 weeks.

When treating complicated or secondary acute pyelonephritis, it must be remembered that if anatomical or functional disorders of the urinary tract, stones, drainages, acute pyelonephritis are not eliminated, it will recur. Patients with permanent drainage in the urinary tract will have a persistent bacteriuria and an exacerbation of the urinary tract infection, despite successful treatment. The risk of such infections can be reduced by observing the rules of asepsis, using closed drainage systems. Strongly recommend not to wash the drains to avoid flushing the biofilms into the pelvis of the kidney followed by bacteremia and kidney re-infection! Intermittent intermittent catheterization of the bladder leads less often to bacteriuria than the installation of permanent catheters. Medication prophylaxis of urinary tract infections in patients with permanent catheters, drainages is not effective.

[28], [29], [30]

Surgical treatment of acute pyelonephritis

Although antibacterial drugs also require the control of sepsis for the spread of infection, if a kidney abscess and perinephric abscess are identified, drainage is performed as a matter of priority. There is an increase in the detailed outcome (65%) in patients treated only medically, compared with patients operated on for kidney abscess (23%). Surgical treatment or nephrectomy is a classic treatment for a dysfunctional or severely infectious kidney, some authors consider it possible to percutaneous aspiration and drainage of the abscess under ultrasound and CT, however percutaneous drainage is contraindicated in large abscesses filled with thick pus.

Surgical treatment of acute pyelonephritis purulent, as a rule, is carried out for emergency indications. Catheterization of the ureter with its occlusion is not always an adequate method of drainage of the urinary tract. However, it is indicated in obstructive acute pyelonephritis due to the stone of the stricture of the ureter, tumor, etc.

It can be performed during the preparation of the patient for surgery, as well as if the patient has severe co-morbidities, when surgical treatment is impossible. The use of ureteral stents (self-retaining catheters) to restore passage of urine in acute pyelonephritis is limited by the inability to monitor the function of the stent and to determine renal diuresis, and also in connection with possible urine reflux into the kidney. Percutaneous puncture nephrostomy can be used according to indications for obstructive acute pyelonephritis. In case of worsening of the patient's condition, the first signs of purulent inflammation in the kidney, despite the functioning nephrostomy, use open surgery to drain the purulent foci (abscess of the kidney, paranephalic abscess).

Before surgery, the patient should be informed of possible complications, in particular, with nephrectomy, to which he must give his written consent.

It must be remembered that the delay in the diagnosis of kidney abscess and perinephric abscess is of great importance for the prognosis of the disease. The importance of differential diagnosis between acute pyelonephritis and kidney abscess, perinephric abscess is of fundamental importance. There are two factors that can help in differential diagnosis:

• in most patients with uncomplicated acute pyelonephritis, the clinical symptoms of the disease developed less than 5 days before admission, while in most patients with perinephric abscess the clinical picture of the disease was more than 5 days;
• in patients with acute pyelonephritis, febrile body temperature lasts no more than 4 days after initiation of antibiotic therapy: in patients with perinephric abscess fever persists for more than 5 days, an average of about 7 days.

Patients with chronic renal failure, polycystic kidney disease are particularly prone to progressing to an acute urinary tract infection in perinephalic abscesses.

Before surgery, in addition to ECG, chest radiography, pulse and blood pressure, information about the function of the contralateral kidney is needed.

The main stages and options for performing organ-saving operations are as follows: after lumbotomy, paranephric fiber is opened, examined for swelling, signs of inflammation. Further, the pelvis and the tuberculosis-ureteric anastomosis are isolated. With pedunculitis, narrownural and paraurethral sclerosis, the altered tissues are removed. They open the pelvis more often in the form of a posterior transverse intrasynthetic pyelotomy.

If there is a stone in the pelvis or in the upper third of the ureter, it is removed. Stones located more low in the ureter are removed at subsequent stages of treatment, after the inflammatory process subsides, more often by DLT. When revising the kidneys, note its increase, edema, venous plethora, a cluster of serous-purulent fluid under the fibrous capsule, abscesses, carbuncles, apostems, infarcts, paranephritis. The further tactics depend on the revealed changes. If it is necessary to drain the kidney nephrostomy it is better to install before opening the fibrous capsule of the kidney. A curved clamp is inserted through the incision into the pelvis and the kidney parenchyma is perforated through the middle or lower cup. The nephrostomy drainage is introduced into the pelvis so that the tip is located freely in its lumen and fix its parenchyma of the kidney along with the fibrous capsule. After suturing the pelvis, the kidneys are decapsulated during indications (to remove the edema and ischemia of the kidney tissue, drain the purulent foci). Pieces of inflammatory changes in the kidney parenchyma are referred to both histological and bacteriological studies. In the presence of carbuncles, they are excised, the kidney abscess either opens or is excised with a capsule. The operation is terminated by a wide drainage of the circumcostal space, excision zones of carbuncles, abscesses and paraneural purulent cavities. Install insurance drains. Do not use topical ointments and antibiotics.

Decision-making about nephrectomy with purulent acute pyelonephritis is difficult and requires a doctor's consultation. There is no unified opinion and there are no conclusive studies on the outcome of purulent acute pyelonephritis. There is no data on nephrosclerosis and shrinkage of the kidneys after organ-saving operations. There are no clear criteria for assessing anatomical and functional disorders in the kidney in acute pyelonephritis to address the issue of nephrectomy.

In each specific case, indications for nephrectomy should be determined strictly individually, taking into account morphological and functional disorders in the kidney, the state of the organism, the state of the other kidney, the age of the patient (especially in children), the presence of concomitant diseases, the nature of the inflammatory process, including the possibility of developing sepsis and other complications in the postoperative period. Nephrectomy can be absolutely shown in purulent-destructive changes in the kidney with signs of thrombosis and involvement in the purulent process of more than 2/3 of the kidney mass, with multiple drainage carbuncles, a prolonged purulent process in the blocked and non-functioning kidney.

Indications for nephrectomy with purulent acute pyelonephritis can arise in weakened patients due to concomitant diseases in the stage of sub- and decompensation, in elderly and elderly people, as well as with urosepsis and after infectious-toxic shock in the unstable state of vital organs. Sometimes nephrectomy is performed during surgery because of life-threatening bleeding from a kidney affected by a purulent process. Sometimes the kidney is removed by the second stage in weakened patients who, in the acute period, according to vital indications, it was possible to conduct only drainage of the perineal abscess or kidney abscess, including percutaneous puncture nephrostomy. With ineffectiveness of antibacterial, detoxification therapy, local treatment in the postoperative period, a decision is made to re-operation - nephrectomy with a wide excision of peri-cellular tissue and draining the wound.

It should be noted that, according to international studies, nosocomial acute pyelonephritis in 24% is complicated by urosepsis. If there is a suspicion of septic complications that include signs of a systemic inflammatory response in the presence of at least one purulent foci of infection, it is necessary to solve the problem of using extracorporeal methods of blood purification and detoxification.

Forecast

Uncomplicated acute pyelonephritis is usually well treated with antibiotic therapy with minimal residual damage to the kidneys. Repeated episodes are rare. In children, acute changes in acute pyelonephritis are usually reversible and do not lead to new renal scarring or loss of kidney function in most cases. Small scars, demonstrated with dynamic nephroscintigraphy, do not reduce the level of glomerular filtration, and there is no difference in kidney function in children with residual scarring and without it. In children with repeated episodes of acute pyelonephritis and large scars on excretory urograms, a lower level of glomerular filtration is noted than in healthy children.

In adult patients, there is rarely a residual decrease in renal function or scars after uncomplicated acute pyelonephritis. Scars on the kidney usually appear due to reflux-nephropathy, which was a patient's childhood. Despite the benign course of uncomplicated acute pyelonephritis, single cases of acute renal failure associated with this clinical form of acute pyelonephritis, whether patients with one kidney, or abused analgesics, or pregnant women are described. All patients recovered without hemodialysis.

Septic syndrome, characterized by hypotension and disseminated intravascular coagulation, is also relatively rare in patients with acute pyelonephritis. More often it occurs in patients with diabetes mellitus.

[31], [32], [33], [34], [35]