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Kidney fistula
Last reviewed: 17.10.2021
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[Causes of the adhesions of the kidneys
The cause of fusion is the fusion of two metanephrogenic blastema at the earliest stage of embryonic development - before the beginning of migration of the kidneys from the caudal divisions of the embryo. As a result, the processes of migration of kidney structures to the lumbar region of its rotation are violated. Therefore, the fused buds are always dystopic. The growth of methanephros ducts occurs without anomalies, so the histological structure of the kidneys is not disrupted, and the ureters always enter the bladder in a typical place. The vast majority of patients with kidney fistula (88.6%) have abnormal circulation.
Symptoms of the adhesions of the kidneys
The involvement of the kidneys can be one-sided (I-shaped kidney) and bilateral (horseshoe, gley-like or comiform, L-shaped kidney). S-shaped kidney also refers to unilateral adhesions of the kidneys.
Bilateral fusion of the kidneys can be symmetrical (each of the kidneys is located homolaterally) or asymmetric (one of the kidneys is located heterolaterally).
With symmetrical adhesion, the kidneys can be connected by their lower poles. Rarely the upper, forming the so-called horseshoe-shaped kidney, or the whole surface, creating a gley-like or komoobraznuyu kidney.
The horseshoe kidney is the most common form anomaly (0.25% of the population). Among all the vices, it occurs quite often - 2.8%. Usually, the fusion is marked by the lower segments, and in 1.5-3.8% by the upper segments. Horseshoe kidney in 70% of cases has an abnormal blood supply (according to our data - 84.62%). Unusually the structure of the renal calyces: the upper group is more developed, the lower one is underdeveloped.
Diseases in the horseshoe-shaped kidney occur much more often than in normal, from 75 to 80% of observations. According to A.V. Aivazian and AM Voino-Yasenetsky. The pathological process in the horseshoe-shaped kidney is revealed in 68.6% of cases, with the most common hydronephrosis - 41.7%, urolithiasis - 23.6%. Pyelonephritis - 19.4%, AH - 15.2%. In hydronephrosis, the plastic surgery is combined with resection of the isthmus. If you find stones in the kidneys, use all modern methods of treatment, including DLT and KLT. As well as open operational manuals. However, the share of the latter in the structure of surgical treatment decreases year by year due to the appearance of minimally invasive techniques. Treatment of pyelonephritis is aimed at the restoration of urodynamics and the appointment of pathogenetic treatment.
An extremely rare anomaly not described in the NA classification. Lopatkina and A.V. Lulko, refer to the so-called disc-shaped kidney, in which fusion takes place not only by all poles, but also by medial lateral surfaces.
Gleytoobraznaya or komoobraznaya kidney has a common cortex and a fibrous capsule. This extremely rare developmental disorder is diagnosed with a frequency of one case at 26,000 autopsies. In this case, the organ is usually located in the small pelvis homolaterally or heterolaterally. The pelvis is always located anteriorly. In clinical practice, the kidney can be taken as a tumor of the retroperitoneal space and removed.
Asymmetric fusion is characterized by the location of one of the kidneys heterolaterally. This happens for two reasons: the fusion of metanephrogenic blasts with the displacement of one of them to the opposite side or the growth of methanephros ducts into one metanephrogenic blastema and the reduction of the homolateral blastema.
The L-shaped kidney occurs when the lower pole of one kidney and the upper pole of the other are fused, and also when one of them is transversely located. The S-shaped kidney is formed by connecting the lower pole of one with the upper pole of the other and with their vertical arrangement. With the S-shaped kidney, the calyxes of one half of the kidney are laterally oriented, the calyx of the second is medially. If the embryonic rotation is completed and the calyxes of both kidneys are directed in one direction, then this kidney is called I-shaped. Thus, I-shaped and S-shaped kidneys can be attributed to unilateral fusion.
Where does it hurt?
Diagnostics of the adhesions of the kidneys
Diagnosis of shape anomalies does not cause difficulties. Already at the stage of ultrasound, it is possible to obtain information about the appearance of one or another fusion of the kidneys, as well as the pathological processes in it.
The advantages of MRI and MSCT before angiography are less invasiveness of the study, as well as more complete information on the state of the renal parenchyma, urinary tract and relationships with neighboring organs.