Pionephrosis is a purulent-destructive kidney disease, which is a necrosis of the renal tissue at the final stage of the acute inflammatory process of the urinary tract. It is manifested by constant aching pain in the lumbar region, increased body temperature, pronounced symptoms of general intoxication. With an open form of pyonephrosis, cloudy urine with an admixture of pus is released. Diagnosis is carried out using physical methods, laboratory tests, instrumental studies (ultrasound and CT of the kidneys, urography, nephroscintigraphy). The main method of treatment is surgical, with complete removal of the affected kidney (nephrectomy).
ICD 10
N13.6 Pionephrosis
Meaning
Pionephrosis, or purulent kidney, is a serious problem of modern urology associated with a high percentage of disability (70%) and death (up to 28%). The frequency of occurrence of pionephrosis in Russia is 200 thousand cases per year or 2 patients per 100 thousand population, but the last five years there has been an increase in the incidence. Pionephrosis complicates inflammatory kidney diseases in 20% of cases, has a positive correlation with the gender and age of patients.
The female excretory system is anatomically more predisposed to infectious diseases, so pionephrosis in women is 5 times more common. In male patients, pathology develops mainly at the age of over 40 years on the background of prostatitis and chronic cystitis.
Causes
The main etiological factor is conditionally pathogenic or pathogenic microflora, which causes inflammation, and then suppuration, damaging the filtration apparatus of the kidneys. The main pathogens are Staphylococcus, Streptococcus, Mycobacterium tuberculosis. Against the background of immunodeficiency or inadequate therapy of infectious diseases of the urinary system, pyonephrosis progresses rapidly with the formation of cavities filled with pus, primary urine, tissue necrosis products. According to clinical observations, the main causes of purulent kidney are:
- Urinary tract infections. Pionephrosis completes the course of pyelonephritis, tuberculous kidney damage, ascending urethritis, cystitis. The reasons for the progression of the purulent process may be the choice of incorrect tactics of antibacterial therapy or inaccurate patient compliance with medical prescriptions.
- Catheterization of the bladder. The infectious process often manifests itself after using a non-sterile urological catheter, especially a rigid one, or due to violation of the rules of its placement with damage to the walls of the urinary tract.
- Anomalies of the genitourinary system. Doubling of the kidney and ureters, the formation of a horseshoe kidney or its omission disrupt the physiological dynamics of urine movement. Stagnant processes are a favorable environment for the development of infection.
- Urolithiasis. The formation of stones in the renal pelvis or ureters creates an obstacle to the normal passage of urine. Urolithiasis worsens uro- and hemodynamics, which complicates local immunity, increases the risk of infection.
Pathogenesis
The infectious agent causes the development of an inflammatory process in the renal tissue. The blood flow increases, the permeability of the renal vessels increases, edema forms. Purulent cavities appear in the parenchyma. Further development of inflammation leads to the formation of scars, expansion of the pelvis, disruption of blood flow and outflow of constantly produced urine, which worsens the course of the disease. With pionephrosis, the kidney is available for palpation, bumpy, enlarged in size.
If surgical removal of an organ is performed at this stage, then cavities with thick walls filled with thick, fetid pus are found on the incision. Sometimes, during the course of pionephrosis, the kidney’s own tissue is replaced by dense fatty tissue. Fatty degeneration is the reaction of the nephral structures to the deterioration of blood supply and oxygen starvation of tissues. Pionephrosis often develops as a unilateral process, but with severe immunodeficiency it can be bilateral.
Classification
In urology, there are two forms of pionephrosis: open and closed. Classification is based on the presence or absence of communication of a parenchymal purulent focus with the rest of the urinary tract. In the open form, the products of infectious suppuration enter through the ureter into the external environment, being determined in urine tests. A closed form with a one-sided course of the process assumes the presence of a strong connective tissue capsule around the focus, which restrains pus, blocking the outflow of urine from the damaged organ. Urine is excreted from a healthy kidney, so laboratory tests do not detect signs of inflammation. In the absence of adequate therapy, the closed form becomes open.
Symptoms
Clinical symptoms depend on the patency of the urinary tract. Layering the symptoms of pyonephrosis on the manifestations of the underlying disease presents additional diagnostic complexity. The general condition of patients in the first 24 hours of the disease is satisfactory. There is constant pain in the lower back of moderate intensity with irradiation to the inner thigh or genitals. Body temperature is normal or increased to 37-38 ° C.
With the development of suppuration, an acute phase of the disease occurs with an increase in pain, a change in its nature to paroxysmal. The body temperature rises to 40-41 ° C, symptoms of general intoxication appear: chills, headache, weakness, reflex nausea and vomiting. With the bilateral nature of the process, symptoms of kidney failure and general exhaustion of the body develop. The functions of the immune system decrease, which often leads to the addition of a secondary infection — influenza, pneumonia, stomatitis.
The main symptom of the open form of pionephrosis is the release of cloudy urine containing decay products and inflammation of tissues (pyuria). The content of pus on the total volume of urine can reach 10%. The degree of pyuria and clinical symptoms depend on the form of pionephrosis. With the closed nature of the course of pain in the lumbar region of greater intensity, sometimes by the type of renal colic. The urine is transparent, but when the closed form turns into an open one, it becomes cloudy. Opening the purulent focus capsule leads to an improvement in well-being, a decrease in body temperature. The open form, in which the normal outflow of pus persists throughout the disease, fever and general intoxication of the body are less pronounced or absent altogether.
Complications
Late diagnosis or lack of full-fledged therapy of the purulent process leads to irreversible changes in the renal tissue, increasing the risk of deadly complications. Unilateral pyonephrosis is characterized by an increased load on a healthy kidney with a gradual violation of metabolic processes. Kidney amyloidosis is formed with intracellular accumulation of a special protein-carbohydrate complex, which leads to renal failure. The formation of a large focus also leads to complications, damage to the capsule of which with the breakthrough of pus into the abdominal cavity and retroperitoneal space leads to potentially lethal conditions: paranephritis, peritonitis, sepsis.
Diagnostics
If signs of the disease occur, it is necessary to contact a surgeon or urologist for examination. Physical diagnosis of pyonephrosis consists of collecting complaints, palpation of the kidneys and bladder. With suppuration, the organ is painful, enlarged in size, has a non-uniform surface and limited mobility in the retroperitoneal space.
Of the diagnostic methods used:
- Urinalysis. With the help of the study, an inflammatory process in the kidneys is diagnosed, the signs of which are turbidity of urine with a significant sediment, a high content of leukocytes, pronounced proteinuria, bacteriuria, specific protein cylinders, mucus.
- Blood test. It shows the presence of inflammation and activation of immunity in the body, which are characterized by a high level of white blood cells, an increased rate of erythrocyte sedimentation.
- Biochemical blood analysis. It reveals an increased level of urea, creatinine, electrolytes — indicators of a decrease in the ability of the kidneys to filter blood from toxins.
- Sowing urine. The study makes it possible to identify the microorganism that caused the infection. When choosing a treatment regimen, it helps to prescribe adequate antibacterial therapy aimed at a specific pathogen.
- X-ray diagnostics. With a review urography, the shadow of an enlarged kidney with clear contours is visible on the X-ray. Stones are often found in the renal pelvis or ureter, creating a mechanical barrier to the outflow of pus. Additionally, angiography of renal vessels is used to assess the level of blood supply to the organ. CT of the kidneys also determines the focus, but allows you to distinguish a cavity filled with pus from a tumor or cyst.
- Ultrasound of the kidneys. It helps to localize the inflammatory focus, determine its shape, assess the quality of urodynamics in the pelvis and ureters.
- Radioisotope renography. Nephroscintigraphy is prescribed to assess kidney function and the degree of renal insufficiency.
Treatment
Treatment of pathology is operative — nephrectomy or nephroureterectomy, if suppuration has arisen due to narrowing of the lumen of the lower ureter. Promotes speedy healing, reduces the risk of complications, removal of not only the kidney itself, but also the perinephrine fatty tissue. In severe cases, organ tissue and purulent foci are removed by minimally invasive methods inside the capsule. Preparation for a planned nephrectomy takes place within 1-1.5 weeks in a hospital setting. A comprehensive assessment of the patient’s condition, consultations with a therapist, a nephrologist, a cardiologist, an anesthesiologist are necessary.
Patients with a tense closed form of pyonephrosis undergo emergency surgery to prevent the development of peritonitis and sepsis. In patients with severe concomitant diseases, impaired functioning of the second healthy kidney or bilateral pionephrosis, the first stage of the operation consists in the imposition of a nephrostomy that allows the purulent focus to drain. Additionally, intensive antibacterial, detoxification therapy is prescribed, plasmapheresis is performed. When the condition is stabilized, radical surgery becomes possible.
Prognosis and prevention
After a well-conducted radical surgical intervention and with the correct behavior of the patient, the prognosis is favorable, the risk of complications is minimized. A lifelong diet is prescribed, fluid intake is reduced to 1.5 liters per day, physical and emotional loads are limited. Dispensary monitoring includes monitoring the function of the remaining kidney, regular urine and blood tests. With bilateral nephrectomy, it is necessary to undergo hemodialysis throughout life or kidney transplantation.
Prevention of pyonephrosis is aimed at preventing the development of inflammatory diseases of the genitourinary system: hypothermia should be avoided, and the resulting foci of infection in the body should be treated in time and in full. Adequate therapy is based on the use of narrow-spectrum antibacterial drugs after laboratory determination of a specific pathogen.