Paranephritis is an infectious and inflammatory lesion of the perinephrine tissue. It is manifested by varying intensity of pain in the lower back, abdominal cavity, which increases with movements and inhalation, fever, chills, weakness, local pasty and hyperemia of the skin in the area of the affected kidney, forced position of the patient (bending of the spine, bending of the leg). It is diagnosed by ultrasound and CT of the kidneys, overview, excretory urography, puncture biopsy. The basis of conservative therapy of paranephritis is the appointment of antibacterial drugs. Surgical treatment is aimed at the rehabilitation of purulent foci by methods of lumbotomy, puncture drainage.
ICD 10
N15.1 Abscess of the kidney and parotid tissue
Meaning
For the first time, the clinic of inflammation of the paranephral fiber was described in 1839 by the French dermatologist Pierre Rayet. The prevalence of paranephritis does not exceed 0.3%. Up to 80% of cases of the disease occur against the background of existing renal pathology (urolithiasis with obstruction of the urinary tract, purulent pyelonephritis, abnormalities in the development of urinary organs, kidney surgery).
Paranephritis is usually diagnosed in patients aged 16-52 years, mainly men. More often, the posterior part of the amniotic tissue suffers, the pathological process is usually one-sided and affects the left kidney. According to the observations of specialists in the field of urology, the probability of developing the disease increases in patients with diabetes mellitus.
Causes
The direct causative agents of pararenal inflammation are pathogenic and conditionally pathogenic bacteria. In 70% of cases, paranephritis is caused by various strains of staphylococci, less often by E. coli, proteus, streptococci, pneumococci, gonococci, pseudomonads, tuberculous mycobacteria, and other microorganisms. Microbial contamination of paranephron is promoted by:
- Purulent-inflammatory renal pathology. Paranephritis is complicated by apostematous nephritis, pionephrosis, carbuncle, kidney abscess, purulent perinephritis, renal tuberculosis, urolithiasis.
- Diseases of neighboring organs. Purulent melting of the fatty capsule of the kidney occurs when infection spreads from the inflamed appendix, blind and ascending colon. Inflammation can also develop against the background of hepatic abscess, purulent cholecystitis, pancreatitis, paracystitis, parametritis, retroperitonitis, etc.
- Distant purulent foci. Paranephritis may occur in patients with boils, carbuncles, panaritia, angina, chronic tonsillitis, purulent otitis, osteomyelitis. The provoking factor is often the formation of an amniotic hematoma due to a bruise of the lumbar region.
In rare cases, inflammation is caused by microorganisms that live in the external environment or on the skin. They get into the paranephral tissue with direct penetrating wounds during accidents, falls on sharp objects, during puncture of renal tissue, attacks using cold and firearms. In some cases, the primary infectious focus remains unidentified.
Pathogenesis
The fatty renal capsule can be infected by contact, lymphogenic, hematogenic pathways. In the presence of distant purulent foci, infectious agents (most often Staphylococcus aureus) spread hematogenously to intact pararenal tissue, which leads to the development of primary paranephritis. Less often, its beginning is facilitated by the impregnation of adipose tissue with blood in closed injuries.
In patients suffering from urological pathology, inflammatory processes in the abdominal cavity, retroperitoneal and pelvic tissue, infection occurs in contact, through lymphatic vessels and anastomoses, and paranephritis itself is secondary. Usually, the lymph nodes located in the more developed fiber behind the kidney are the first to be involved in inflammation. From the lymph nodes, bacteria enter directly into the adipose tissue, causing a classic inflammatory reaction.
Alterative processes contribute to the exudation of intravascular fluid and leukocytes into the fiber with the appearance of infiltrative paranephritis, which, with adequate therapy, is often reversible. In more severe cases, focal or total purulent abscess formation occurs with further melting of the interfacial septa and the spread of the inflammatory process. Acute inflammation ends with a recovery phase or acquires a chronic course, followed by the proliferation of inflammatory-altered adipose tissue and sclerosis.
Classification
In addition to the isolation of primary and secondary forms of inflammation, paranephritis is classified taking into account the localization, nature of pathological changes, and features of the development of the clinical picture. This approach allows you to correctly assess the prognosis of the disease and choose the optimal therapeutic tactics. Based on the features of the location in the pararenal tissue, there are upper (endodiaphragmal), lower, posterior, anterior, total inflammation of the paranephron.
According to the type of pathological process, paranephritis can be infiltrative, purulent (abscessing or phlegmonous), scar-sclerosing (fibrotic-sclerotic or fibrotic-lipomatous). Taking into account the peculiarities of the course and symptoms in practical urology , there are:
- Acute paranephritis. Observed more often. It is characterized by a turbulent clinical picture with infiltrative and purulent processes, a high risk of severe complications with the spread in the retroperitoneal space, the possibility of chronicling the process and the development of productive inflammation. With adequate treatment, it undergoes reverse development.
- Chronic paranephritis. It is less common. It is an acute or primary chronic outcome. In the absence of an acute phase, it usually complicates the course of recurrent calculous pyelonephritis or renal tuberculosis. It can be “armored” (with the formation of connective tissue arrays in the perinephrine tissue) or fibrotic-lipomatous.
Symptoms
Acute primary inflammation of the paranephron usually begins with the sudden appearance of general intoxication symptoms. The body temperature rises to 39-40 ° C, the patient experiences chills, general weakness, sweating. Appetite worsens, bloating and constipation are often noted. Local symptoms occur on the 2-3 day of the disease. Patients with acute paranephritis complain of intense pain in the lower back, abdomen, less often in the hypochondrium. Painful sensations increase with deep breathing, walking, and movements. There is a local tension of the musculature in the projection of the affected kidney.
The lower and posterior paranephritis is characterized by the forced position of the patient with the knee bent to the abdomen on the side of the lesion. Local hyperthermia, pasty tissues, redness of the skin are detected. Sometimes the spine is scoliotically curved in a healthy direction. With a fairly rare upper paranephritis, due to the involvement of subdiaphragmatic fiber in the process, the excursion of the diaphragm is limited, shortness of breath and a feeling of lack of air occur. The increase in inflammation is accompanied by a worsening of the patient’s condition — the appearance of deafness, confusion, increased breathing and heartbeat.
The acute form of secondary paranephritis is often manifested by aggravation of the already existing clinic of kidney, abdominal or pelvic organ damage with increased pain in the lower back and hyperthermia. In the chronic process, pathognomonic symptoms are usually absent, the only complaint of patients is dull soreness in the kidney area. It is possible to squeeze the roots of spinal nerves passing nearby with the appearance of pain, numbness, tingling, crawling sensations on the skin in the lumbosacral region, hip, less often — the lower leg. Sometimes subfebrility is noted.
Complications
With untimely diagnosis and insufficient therapy, paranephritis is usually complicated by the spread of inflammation with the development of retroperitoneal phlegmon or the breakthrough of an abscess into the abdominal, pleural cavities, pelvis, rectum, bladder, under the skin in the area of the 12th rib or above the crest of the ilium. In such patients, peritonitis, pleural empyema, paraproctitis, parametritis are observed, renal fistulas are formed. With hematogenic generalization of the process, sepsis and infectious-toxic shock are possible. Compression of the renal parenchyma and blood vessels in chronic sclerotic and fibrotic-lipomatous paranephritis provokes the development of nephrogenic arterial hypertension.
Diagnostics
In the chronic course and at the infiltrative stage of acute paranephritis, when there are no local symptoms, diagnosis is often difficult. A certain role is played by a physical examination, which allows visually determining the reaction from the skin and muscles, curvature of the spinal column, palpation to identify infiltrate, features of the location and nature of the kidney surface, positive symptoms of Pasternatsky and Israel. Instrumental methods are the most informative for the diagnosis of paranephritis:
- Echography. Ultrasound of the kidneys makes it possible to detect and clearly localize foci of purulent melting, represented by hypoechoic or anechoic rounded formations with a clear contour. In the chronic variant of paranephritis, the heterogeneity of the echostructure of tissues is determined. More accurate data can be obtained during kidney CT.
- Radiography. On survey urograms, the vertebral column is often scoliotically curved in the lumbar region, the contour of the lumbar muscle near the affected kidney is clearly smoothed or not visible. Depending on the localization and size of the paranephral infiltrate, the kidney has a normal or smoothed contour. Sometimes the renal parenchyma is not visualized on the X-ray. According to intravenous urography, the ureter on the paranephritis side is often rejected laterally or medially. When conducting a study during respiration, a significant restriction or lack of mobility of the affected kidney is revealed. Due to compression by inflammatory infiltration, the pelvis and calyx may look deformed.
- Diagnostic puncture. It is rarely performed, mainly in cases of clearly delimited infiltration. The detection of pus in the amniotic fat capsule is a direct confirmation of paranephritis. The obtained material is examined microbiologically to determine the pathogen and establish its sensitivity to antibiotics.
According to the indications, the nephrologist prescribes consultations of an abdominal surgeon, pulmonologist, gastroenterologist, infectious disease specialist, phthisiologist, oncologist. An auxiliary role in the examination is played by fluoroscopy, which confirms the limited mobility and high standing of the diaphragm, the presence of pleural effusion from the lesion. Nephroscintigraphy is performed to assess the functional state of the renal tissue.
In a blood test, general inflammatory changes are detected: a significant increase in the content of leukocytes, a shift in the leukocyte formula to the left, high ESR. The levels of erythrocytes and hemoglobin may decrease. Leukocyturia, bacteriuria in the general analysis of urine are detected only with primary damage to the renal parenchyma. In severe paranephritis, signs of toxic damage to the filter apparatus are possible: microhematuria, cylindruria, albuminuria.
Differential diagnosis
Paranephron inflammation is differentiated with:
- pionephrosis
- tumors and kidney cysts
- retroperitoneal phlegmon of other origin
- paracolitis
- hepatic and subdiaphragmatic abscess
- appendicitis, appendicular infiltrate,
- retrocecal abscess
- acute cholecystitis
- pleurisy and pneumonia.
With severe variants of the course and the absence of local “renal” symptoms in the first days of the disease, differential diagnosis of paranephritis with influenza, typhus, malaria may be required.
Treatment
Patients with acute inflammation of the paranephron are recommended to be urgently hospitalized in a urological hospital. In chronic variants of paranephritis, prehospital examination is possible, followed by planned outpatient or inpatient treatment. The choice of conservative or operative tactics of patient management depends on the nature of inflammatory changes and the form of the course of the disease:
- In acute infiltrative paranephritis. Treatment begins with the appointment of antibiotics. The detection of gram-positive flora serves as an indication for the use of semi-synthetic penicillins, macrolides, cephalosporins of the 2nd-3rd generation in combination with sulfonamide preparations. Aminoglycosides and fluoroquinolones are recommended for the elimination of gram-negative microorganisms. The use of antibacterial agents is supplemented with detoxification, immunomodulatory and vitamin therapy.
- In acute purulent paranephritis. Surgical rehabilitation of the infection focus is required. To remove pus, puncture drainage is more often performed, less often — a wide opening of the abscess (lumbotomy). In patients with posterior paranephritis, it is possible to perform an intervention through intermuscular access. When paranephral inflammation is combined with pionephrosis, nephrostomy is performed first, and then nephrectomy. After operations, antibacterial therapy with broad-spectrum drugs is prescribed, taking into account the type of pathogen.
- With chronic paranephritis. Treatment can be both conservative and surgical. In the absence of a closed purulent focus and pyonephrosis, antibiotics are usually used in combination with glucocorticosteroids, resorbing, restorative agents, physiotherapy procedures. Surgical intervention to remove the abscess is chosen according to the same principles as in acute inflammation. Compression of the kidney during sclerosing of the fiber is an indication for excision of the paranephron.
Therapy of all forms of paranephritis is effectively complemented by physiotherapy: diathermy, UHF, mud and paraffin applications, massage, UVI. In the presence of purulent-septic complications with severe intoxication syndrome and impaired renal filtration, extracorporeal detoxification is recommended — hemosorption, plasmapheresis, plasmosorption, hemodialysis.
Prognosis and prevention
Timely detection and adequate antibacterial therapy make it possible to stop most cases of acute paranephritis at the initial infiltrative stage without surgery. The correct choice of the method and time of surgical intervention in purulent inflammation ensures rapid sanitation of the abscess and preservation of the kidney.
The prognosis of chronic paranephritis is determined by the state of renal functions and urodynamics. Prevention of the disease is aimed at timely treatment of urological diseases, rehabilitation of foci of chronic infection, prevention of common purulent complications in abdominal and pelvic pathology, strengthening immunity.