Kidney tuberculosis is an extrapulmonary infection caused by Mycobacterium tuberculosis and affecting the renal parenchyma. The clinic is nonspecific, may include malaise, subfebrility, lower back pain, macrohematuria, dysuria. Kidney tuberculosis is diagnosed using laboratory urine tests, tuberculin diagnostics, kidney ultrasound, urography, retrograde ureteropyelography, nephroscintigraphy, morphological examination. Treatment involves the appointment of specific anti-tuberculosis therapy; with a destructive process in the kidneys, cavernectomy or nephrectomy may be required.
ICD 10
A18.1 Tuberculosis of the genitourinary organs
Meaning
Among organ extrapulmonary lesions, renal tuberculosis (nephrotuberculosis) is the most common form of the disease and occurs in urology in 30-40% of cases. Initially, the cortical layer of the organ is affected. Further progression of the infection is accompanied by the disintegration of tissues, the formation of cavities and cavities in the renal parenchyma, impaired kidney function. In severe cases, there is the development of tuberculous pyonephrosis (purulent melting of renal tissue), involvement in the infectious process of the pelvis, ureter, bladder, genitals.
With kidney tuberculosis, genital tuberculosis often develops, affecting the prostate, testicles, appendages of the testicles in men (tuberculous prostatitis, orchitis, epididymitis); in women – appendages, fallopian tubes, uterus (tuberculous salpingoophoritis, salpingitis, endometritis).
Causes
The causative agents of kidney tuberculosis are Mycobacterium tuberculosis (M. tuberculosis). As a rule, pathology occurs in patients with advanced pulmonary or bone tuberculosis after 3-10 years of the course of the primary tuberculosis process. The development of the disease, as a rule, occurs against the background of existing local infectious or urodynamic processes – chronic pyelonephritis, kidney stones, etc.
Pathogenesis
The penetration of infection into the kidney occurs mainly by hematogenic route. Getting into the glomerular apparatus with the blood flow, mycobacteria form multiple tiny tuberculous foci. With good local and general resistance to infection and the small size of the primary foci, the latter can undergo complete reverse development. With disorders of urodynamics and hemodynamics, as well as reduced protective forces from the cortical layer, the infection spreads to the medulla, causing a specific inflammation of the renal papillae – tuberculous papillitis.
With the further development of tuberculosis, the entire thickness of the renal pyramids is involved in the process, the caseous decay of the latter occurs, which is accompanied by the formation of isolated or communicating with cup-pelvic complexes of caverns. The progression of renal tuberculosis can lead to the formation of multiple cavities in the renal parenchyma (polycavernous form) and the development of pionephrosis. Subsequent healing of caverns proceeds with calcification of caseous foci, in which, however, viable Mycobacterium tuberculosis can persist.
Secondary involvement of the bladder, ureters and cup-pelvic complexes is associated with a lifogenic or urinogenic mechanism of the spread of tuberculosis infection.
Classification
In clinical urology, a classification has been adopted that takes into account the clinical and radiological features of kidney tuberculosis. According to this classification, there are:
- Tuberculosis of the renal parenchyma, accompanied by the formation of multiple foci in the cortical and medullary layer of the kidney.
- Tuberculous papillitis, occurring with damage to the renal papillae.
- Cavernous kidney tuberculosis, characterized by the fusion of destructive foci with encapsulation (cavity form).
- Fibrous-cavernous kidney tuberculosis, accompanied by obliteration of the cups with the formation of closed destructive-purulent cavities in them.
- Mistletoe (calcification) of the kidney, expressed in the formation of limited pathological foci with a large amount of calcium salts (caseoma, tuberculosis).
Symptoms
There are no pathognomonic symptoms. In the early stages, the pathology may have a latent course or be characterized by disorders of general well-being: mild malaise, fatigue, subfebrile temperature, progressive weight loss. Destructive changes in the kidneys are accompanied by the appearance of pain-free total hematuria caused by vascular erosion during ulceration of the renal papillae. Bleeding is often replaced by pyuria, indicating the development of pyelitis or pyelonephritis.
With cavernous kidney tuberculosis, there are signs of infectious intoxication, lower back pain. Pain sensations, as a rule, are moderately expressed, have a nagging dull character, however, with violations of the outflow of urine, they can progress to renal colic. Bilateral urodynamic disorder is accompanied by signs of chronic renal failure. With tuberculous cystitis, dysuric phenomena are joined – imperative urge to urinate, pollakiuria, stranguria, constant pain over the womb, periodic macrohematuria. In the advanced stages of the disease, arterial hypertension often develops.
Diagnostics
Given that renal tuberculosis can occur asymptomatically or in the form of various clinical variants, laboratory and hardware-instrumental studies are of paramount importance in the diagnosis. If kidney tuberculosis is suspected, a tuberculin test and a consultation with a phthisiologist are indicated. When collecting anamnesis, they find out the fact of the presence of pulmonary tuberculosis in the patient and his relatives, contacts with tuberculosis patients. In thin patients, in some cases, it is possible to palpate a dense, bumpy kidney. A pronounced symptom of Pasternatsky is determined.
Characteristic changes in the general urinalysis are persistent sharply acidic reaction, leukocyturia, proteinuria, erythrocyturia, pyuria. Reliably judge the presence of kidney tuberculosis allows the detection of mycobacteriuria, which is detected by bacteriological urine culture or PCR studies. Conducting ELISA allows you to detect antibodies to tuberculosis, gamma interferon (quantiferon test) or sensitized T cells (T-spot.TB). In certain cases, provocative tests with tuberculin are required. After subcutaneous administration of tuberculosis antigen, the process is aggravated, which is accompanied by pronounced proteinuria, pyuria and mycobacteriuria.
Ultrasound of the kidneys with their tuberculous lesion makes it possible to identify cavities, calcified foci, assess the degree of involvement of the renal parenchyma and the dynamics of regression of the disease under the influence of therapy. X-ray examination of the kidneys (overview urography, intravenous urography, retrograde ureteropyelography and antegrade pyelography) help to comprehensively assess the condition of the parenchyma and the cup-pelvic apparatus of the kidneys, ureters, and bladder. Performing renal angiography makes it possible to determine intra-organ angioarchitectonics if kidney resection is necessary.
Kidney CT and MRI have wide diagnostic capabilities. Data on the functional state of the kidneys in tuberculosis are obtained using radioisotope nephroscintigraphy. A kidney biopsy is dangerous by dissemination of the infectious process, however, according to indications, a cystoscopy with a biopsy of the bladder mucosa can be performed. Morphological examination of the biopsy of the bladder in some cases makes it possible to detect giant Pirogov-Langgans cells even in the absence of visual changes in the mucosa. Differential diagnosis is necessary with hydronephrosis, nonspecific pyelonephritis, spongy kidney, megacalicosis, polycystic kidney.
Treatment
Treatment for kidney tuberculosis can be medicamental and combined (surgical and medicamental). Drug treatment of nephrotuberculosis includes the appointment of specific anti-tuberculosis drugs of different groups for a period of 6 to 12 months (rifampicin, isoniazid, ethambutol, pyrazinamide, protionamide, streptomycin, etc.).
The combination of first-line drugs with fluoroquinolones (ofloxacin, ciprofloxacin, lomefloxacin) is promising. Specific chemotherapy for kidney tuberculosis is supplemented by the appointment of angioprotectors, NSAIDs that prevent scarring of renal tissue. It should be borne in mind that long-term treatment with anti-tuberculosis drugs can lead to severe intestinal dysbiosis, allergic reactions.
In case of violation of the outflow of urine from the kidney, the installation of a ureteral stent or nephrostomy is required. In case of development of a local destructive process in the kidney, conservative therapy is supplemented with rehabilitation of the affected segment (cavernotomy) or partial resection of the kidney (cavernectomy). With total destruction of the organ, nephrectomy is indicated.
Prognosis and prevention
The main prognostic criterion is the stage of the disease. Early detection of nephrotuberculosis, the absence of destructive processes in the cup-pelvic system, ureters and bladder against the background of adequate specific chemotherapy can be accompanied by a complete cure. Unfavorable in terms of prognosis is bilateral kidney tuberculosis with pronounced destruction of the renal parenchyma.
All patients who have suffered from this disease are registered at the dispensary by a phthisiologist and a nephrologist with periodic examination. The criteria for cure are normalization of urine parameters, absence of recurrence of nephrotuberculosis according to X-ray data for 3 years. Prevention of kidney tuberculosis consists in compliance with specific measures (vaccination against tuberculosis) and non-specific prevention of pulmonary tuberculosis.
