Urethral syndrome is a laboratory syndrome that includes proteinuria, hematuria, leukocyturia and cylindruria. The listed violations occur all together or manifest themselves in various combinations of 2-3 signs. Pathology is observed in glomerulonephritis, pyelonephritis, urolithiasis and other types of kidney damage. The main symptoms: swelling on the face, pain in the lower back or lower abdomen, dysuric phenomena. To diagnose the cause of the syndrome, ultrasound, MRI of the kidneys, X-ray examinations (CT, excretory urography, renoscintigraphy) are prescribed. Treatment is selected taking into account the main and concomitant diseases.
ICD 10
R30-R39 Symptoms and signs related to the urinary system
Meaning
In a broad sense, the concept of “urethral syndrome” includes all quantitative and qualitative changes in urine, which are determined by laboratory examination. However, in practical urology and nephrology, doctors use a narrower interpretation of the term. Traditionally, it includes 4 indicators: an increase in the content of protein in the urine (proteinuria), erythrocytes (hematuria), leukocytes (leukocyturia) and cylinders (cylindruria). Urethral syndrome occupies a leading place in patients with kidney damage, is the main sign of acute and chronic pathology of the urinary system.
Causes
Asymptomatic urethral syndrome may have a physiological origin, especially when isolated proteinuria is detected. It develops with intense physical and psychoemotional stress, feverish states, and the use of a large amount of protein food. The spectrum of pathological causes of laboratory syndrome is diverse, most often changes in urine occur in the following groups of diseases:
- Glomerulopathy. Diseases that occur with the defeat of the glomerular apparatus are accompanied by violations of the renal filter and the penetration of pathological inclusions into the urine. Typical causes of urethral syndrome include glomerulonephritis, diabetic nephropathy, acquired amyloidosis. Among hereditary diseases, Alport syndrome, lipoid nephrosis are distinguished.
- Tubulopathy. Damage to the renal tubules is manifested by impaired transport of organic substances and electrolytes, a large number of cylinders in the urine. Common variants of tubulopathy include necrotic nephrosis, urate nephropathy, and myeloma nephropathy. In children, pathology occurs against the background of de Toni-Debre-Fanconi syndrome, Albright syndrome.
- Interstitial kidney diseases. The most common renal cause of massive leukocyturia is pyelonephritis, which occurs when infected with bacterial pathogens. Various forms of urethral syndrome are typical for tubulo-interstitial nephritis, which develops under the influence of toxins, infections, metabolic disorders.
- Urolithiasis. Nephrolithiasis is manifested by crystalluria – the accumulation of pathological salts in the urine, it is also characterized by leukocyturia, erythrocyturia. With the formation of large stones and damage to the mucous membrane of the calyx-pelvic system, massive hematuria develops, which must be distinguished from bleeding against the background of tumor decay.
- Urological diseases. Urethral syndrome is a constant companion of cystitis and urethritis. The nature and intensity of changes in laboratory parameters depends on the characteristics of the course, duration and severity of the disease. Intense hematuria may indicate hemorrhagic cystitis, bladder tumors.
Pathogenesis
Normally, the kidneys have an anatomical barrier that includes a complex glomerular filter that does not allow large molecules and cells to pass through. The diameter of the pores is up to 4 nm, so only light chains of proteins can pass through them. In pathological conditions, the pores increase in size, due to the deposition of immune complexes and the development of inflammation, the permeability of the vascular wall for macromolecules increases.
The mechanism of hematuria formation is not fully elucidated. A significant role in the development of this symptom is the involvement of mesangia, lesion of interstitial tissue and epithelium of convoluted tubules. According to electronograms, red blood cells are able to change their shape and penetrate into the urine through the smallest ruptures of the basement membrane. The second variant of hematuria is associated with damage to the urinary tract mucosa in urological diseases.
The appearance of leukocyturia is associated with inflammatory processes in any part of the urinary system, in response to which immune cells migrate to the pathological focus. The number of leukocytes in the field of vision depends on the activity of the disease – from minor leukocyturia (8-10 cells) to pyuria (leukocytes cover more than half of the field of vision). The appearance of cylinders indicates pathological processes in the renal tubules.
Symptoms
Clinical manifestations depend on the root cause of laboratory changes and the severity of the disease in a particular patient. On external examination, attention is drawn to “facies nephritica” – a puffy face with pale skin, swollen eyelids and narrowed eye slits. With prolonged existence of edema, the skin becomes dry and thinned, covered with light streaks of stretching. For amyloidosis, the waxy pallor of the skin is typical.
Many diseases that appear with urethral syndrome cause pain in the lower back. Patients complain of dull aching pains with glomerulonephritis and chronic pyelonephritis, strong cramping sensations with irradiation into the perineum with kidney stones. Symptoms are aggravated by heavy drinking, jolting driving, physical exertion. Urinary tract diseases are manifested by pain in the lower abdomen during urination.
Another typical sign of a lesion of the urinary system is a violation of the urination process. Patients note more frequent trips to the toilet, increased pain during the process, imperative urges. A change in the amount, color and density of urine is characteristic, with purulent-inflammatory processes, a sharp unpleasant odor appears. Red and brown tint of urine indicates hematuria, brown color is a symptom of jaundice.
Complications
The most dangerous consequence of urethral syndrome is the development of renal failure. According to the pathogenesis and clinical symptoms, it can be acute and chronic. Acute renal failure (acute renal failure) reflects necrosis of the epithelium of the tubules and severe circulatory disorders in the organ. With timely treatment, mortality is 10-15%, without medical care – more than 50%, in patients with severe concomitant pathology – up to 80%.
With anatomical and functional lesions lasting more than 3 months, chronic kidney disease (CKD) is diagnosed. This is a dangerous steadily progressive disease, which is accompanied by a gradual decrease in the glomerular filtration rate (GFR). The final stage of CKD is terminal renal failure, which is often accompanied by life-threatening cardiovascular and infectious complications.
Diagnostics
To establish the fact of urethral syndrome, indicators of standard laboratory analysis are necessary. If pathological deviations from the norm are detected, the patient needs to be examined by a nephrologist or urologist to identify the root cause of the disorders. First, a general clinical examination, palpation of the lower back, collection of a life history is carried out. The extended diagnostic program includes the following types of studies:
- Ultrasound of the kidneys. With echosonography, it is possible to detect local areas of increased echogenicity with stones and tumors, or foci of reduced density – abscesses, cysts. Diffuse changes in the renal parenchyma are observed in amyloidosis, nephrocalcinosis, CKD. The increase in the size of the organ is typical for acute kidney failure, congestive nephropathy, polycystic.
- Excretory urography. X-ray contrast examination is used to determine renomegaly, to detect deformity of the contours of the organ, to determine the signs of congenital anomalies. Urography shows signs of pyelonephritis, tumors, CKD. According to the radiography data, it is possible to establish the presence of polycystic, hydronephrosis.
- CT of the kidneys. The modern X-ray examination method is used to clarify the structural anomalies of the organ, to identify minimal changes not noticed in other types of diagnostics. Computed tomography is indicated for suspected tumors, congenital malformations, and chronic diseases. As an alternative, an MRI can be prescribed.
- Renoscintigraphy. Radionuclide scanning is an informative method for determining the functional activity of the kidneys. According to the rate of accumulation and the nature of the distribution of the pharmaceutical, it is possible to detect signs of nephropathy or renal failure, evaluate the effectiveness of treatment, and decide whether surgery is necessary.
- Angiography of the renal arteries. The study is prescribed if there are suspected prerenal causes of organ damage that are associated with aneurysms, thrombosis, arteriovenous fistulas. Angiography is also recommended for patients with cardiovascular problems.
The Rehberg test. Determination of GFR by endogenous creatinine clearance is used to establish the stage of chronic renal pathology and the selection of optimal treatment methods. Additionally, a coagulogram, a biochemical blood test with a proteinogram and a lipidogram is performed.
Treatment
Pharmacotherapy
When selecting treatment methods, the main pathology is taken into account, after which the pathological changes characteristic of the urethral syndrome disappear. Patients are recommended to follow a diet with a limited amount of table salt, strict control of protein levels and fluid intake. The following groups of medications are used to treat kidney disease and normalize organ functions:
- Glucocorticoids. The drugs have a powerful anti-inflammatory and immunosuppressive effect, so they are used for various forms of glomerulonephritis, interstitial nephritis, nephropathies against the background of autoimmune pathologies.
- Antibiotics. Antimicrobials are used in leukocyturia to eliminate bacterial infections of the urinary tract. They are selected empirically with subsequent corrections of therapy based on the results of urine back-up.
- Diuretics. Preparations from the group of loop, thiazide and potassium-sparing agents are prescribed to correct the water-salt balance, reduce renal edema, and prevent cardiovascular complications.
- Cardiotropic drugs. In medical practice, a combination of urethral syndrome with arterial hypertension and other heart diseases is typical, therefore, hypotensive, hypolipidemic, cardiometabolic medications are used in complex therapy.
Extracorporeal detoxification methods
To correct systemic manifestations of renal insufficiency and replace the lost organ function, hemodialysis is performed daily or every other day with acute kidney failure, regularly 1-3 times a week with chronic kidney disease. According to indications, other extracorporeal methods are used: plasmapheresis to remove toxins and metabolic products from blood plasma, continuous therapy procedures (hemofiltration and hemodiafiltration).
Surgical treatment
In case of chronic renal insufficiency, the possibility of radical measures – organ transplantation is being considered. Transplantation is the most effective way to correct the disease, it can significantly prolong the life of patients. The help of surgeons may be required to correct congenital malformations that disrupt the functioning of the kidneys, to eliminate vascular pathologies in the renal artery basin.
Prognosis and prevention
Long-term risks for the patient depend on the root cause of deviations in the urine analysis and the correctness of treatment. In the absence of signs of renal insufficiency and other somatic diseases, it is possible to completely eliminate the problem by conservative treatment methods. After undergoing acute renal failure, up to 50% of those who have recovered have a decrease in kidney function, about 5% need constant renal replacement therapy. CRF requires lifelong supportive treatment.
Since urethral syndrome is not an independent nosology, the essence of preventive measures is to prevent the development of kidney diseases. Patients are advised to adhere to a healthy diet with a restriction of fats and salt, avoid hypothermia, and treat infections of the lower urinary tract in a timely manner. To prevent toxic kidney damage, doctors need to rationally approach the selection of pharmacotherapy, avoid polypragmasia.