Congenital renal anomalies
Congenital renal variations are classified according to disorders of their shape, physical volume, normal count, and anatomical position. The main types include:
- Quantitative changes: Aplasia (or agenesis) is the complete absence of one kidney. The reverse scenario is also possible — the formation of a functioning supernumerary kidney.
- Volume disorders: Hypoplasia is characterized by a pathological decrease in organ size, which is inextricably linked with a reduction in its excretory and functional capabilities.
- Positional changes (dystopia): the kidney may migrate from its typical lumbar bed. There is a thoracic form (high displacement into the chest cavity) and a pelvic form (descended into the pelvic cavity).
- Shape anomalies: the most well-known is horseshoe kidney — a congenital anatomical fusion of the upper or lower poles of two organs.
- Cystic transformations: include solitary cyst (a single fluid-filled cavity lesion in the parenchyma) and polycystic kidney disease. It is important to emphasize that polycystic disease is exclusively a bilateral lesion accompanied by total replacement of normal parenchyma with cysts of various sizes.
Urethral defects: hypospadias and epispadias
Anomalies of the male urethra require complex reconstructive surgery.
Hypospadias is frequently diagnosed — in 1 out of 200–400 infants. The essence of the defect lies in the absence of the distal urethra. Depending on severity, the meatus may be located at the base of the glans, on the penile shaft itself, or in the perineal area. The most severe form is scrotal hypospadias. In this condition, the pendulous part of the penis is completely absent, the scrotum is split into two halves (visually mimicking labia), and urination is performed in a female-like manner.
Epispadias is a much rarer condition (1 case per 50,000). It is a failure of fusion of the anterior wall of the urethra (either only in the distal section or along its entire length). With the complete form of epispadias, patients always exhibit persistent urinary incontinence.
Treatment for both pathologies is exclusively surgical and consists of several mandatory stages: straightening the corpora cavernosa, shifting the urethral meatus to the correct position, and plasty of the urethra itself.
Pathologies of the bladder and testes
Among the most severe congenital defects is bladder exstrophy (incidence 1 in 50,000). In this pathology, the anterior wall of the organ itself and the adjacent area of the anterior abdominal wall are completely absent. The bladder is essentially turned inside out, and its mucous membrane is constantly exposed. Treatment requires immediate surgical care: reconstructive bladder plasty or ureterosigmoidostomy is performed.
Cryptorchidism is the delay in the normal intrauterine movement of one or both testes into the scrotum. The glands remain hidden in the retroperitoneal space or stuck in the inguinal canal. The main primary diagnostic method is routine palpation revealing the absence of the testis in the scrotum. Therapy can be conservative (use of hormonal drugs) or surgical (surgical orchidopexy).
Diagnosis and management tactics
To accurately detect malformations, a wide range of instrumental methods is used: ultrasonography (ultrasound), radiography, computed tomography (CT), scintigraphy, and specific functional tests of renal performance.
Basic treatment principles:
- Conservative and symptomatic management: is the primary method if the anomaly is asymptomatic and there are no threatening complications.
- Surgical removal (nephrectomy): a radical step indicated only for severe complications. The main condition for the procedure is the confirmed presence of a second kidney and the full preservation of its functions.
- Kidney transplantation: performed in patients who develop end-stage renal failure.
To remember the difference between urethral defects: HYPOspadias — the opening is "hidden" BELOW (or the distal part is absent), EPIspadias — defect of the EPIcenter (ANTERIOR/upper wall).
Class and exam questions
Can an anomalous kidney be removed if it is constantly inflamed?
Yes, in the event of severe complications, nephrectomy is indicated. However, it is strictly prohibited if the patient lacks a second healthy kidney with fully preserved excretory function.
How does the scrotal form of hypospadias differ from other types?
This is the most severe form of malformation: the urethral opening is located near the scrotum, the pendulous part of the penis is absent, the scrotum is split into two halves, and urination occurs in a female-like manner.
Is unilateral polycystic kidney disease possible?
No, according to the classification, polycystic disease is always a bilateral process in which the parenchyma of both kidneys is replaced by multiple cysts.
What is the essence of bladder exstrophy?
This is the congenital absence of the anterior wall of the bladder and the anterior abdominal wall above it. As a result, the organ is turned inside out, and the mucosa is completely exposed.
What else to study on this topic
- Surgical technique of nephrectomy in developmental anomalies
- Symptomatic treatment of uncomplicated renal malformations
- Stages of reconstructive plasty in hypospadias and epispadias
- Methods of urinary diversion (ureterosigmoidostomy)
- Hormone therapy in the treatment of cryptorchidism
- Assessment of the functional capacity of a solitary healthy kidney
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Other topics in "CHAPTER 16. CONGENITAL MALFORMATIONS"
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