Posterior urethral valves

Posterior urethral valves (PUVs) are abnormal anatomy of the posterior urethra characterized by the presence of valves or folds that may obstruct the normal flow of urine from the bladder. This condition is more common in boys and can be accompanied by various malformations of the urinary tract, leading to serious consequences, including kidney damage and the development of chronic pain. It is important to note that the pathology can vary in severity: from asymptomatic forms to severe obstruction of the urinary tract. Early diagnosis and adequate treatment are necessary to minimize the risks associated with this disease.

History of the disease and interesting historical facts

Posterior urethral valves were first described in the medical literature in the early 20th century. Initially, attention to this pathology was drawn to a case of neuropathic bladder in a newborn. Since then, the study of PUCs has led to significant changes in the understanding of their pathophysiology and treatment options. One of the first surgical interventions aimed at correcting this anomaly was reported in the 1930s. Since then, surgical techniques have continually evolved due to improvements in technology and imaging techniques that allow more accurate diagnosis and surgery of children with PUCs.

Epidemiology

According to various epidemiological studies, Posterior urethral valves occur in 1:5000 newborns, with 80-90% cases of this pathology observed in boys. Statistics also show that the disease can be associated with other anomalies in the development of the genitourinary system. Multicenter studies suggest that about 15-20% patients with this anomaly have concomitant chronic kidney and urinary tract diseases. Tracking factors such as the presence of PUC in the family can help in understanding the causes and mechanisms of this disease.

Genetic predisposition to this disease

Although the underlying etiology of posterior urethral valves remains unclear, some studies suggest that genetic factors may play a role in their development. In particular, a link has been found with mutations in genes responsible for epithelial and smooth muscle development, such as ENG, ALK, and others. For example, a number of patients with posterior urethral valves have mutations in the RET gene, which is involved in the development of the nervous system associated with the urinary tract. Also, some patients have been found to have chromosomal abnormalities, such as Klinefelter syndrome and other chromosomal defects, indicating a possible genetic predisposition.

Risk factors for the development of this disease

There are several factors that may increase the likelihood of developing posterior urethral valves, including:

• Developmental abnormalities of the genitourinary system, such as underdevelopment of the genitals.
• Environmental factors, including exposure to toxic substances during pregnancy.
• Family history of urinary tract malformations.
• Mother's age over 35 years during pregnancy.
• Changes in hormonal levels associated with pregnancy.

These factors may contribute to the development of pathology, but the exact mechanisms of their influence require further study.

Diagnosis of this disease

Diagnosis of posterior urethral valves begins with clinical evaluation and history taking. Common symptoms include:

• Retention of urine or frequent urination with small volume of urine.
• Monitoring an enlarged or inflamed bladder.
• Possible symptoms of a urinary tract infection.

Laboratory tests may include:

• Urine analysis for the presence of blood and leukocytes.
• Ultrasound examination to determine the condition of the kidneys and bladder.
• Magnetic resonance imaging for a more detailed study of the anatomy of the urinary tract.

Other diagnostic tests may include cystoscopy and contrast radiography of the urinary tract. The differential diagnosis should exclude other causes of urethral and ureteral obstruction.

Treatment

Treatment of posterior urethral valves includes both conservative and surgical methods. Common approaches to therapy include:

• Pharmacological treatment to control infection and improve urinary tract function.
• A surgical procedure aimed at removing the valves and restoring normal urine flow.
• Other methods such as catheterization to relieve symptoms.

The focus is on surgical treatment, which can range from minimally invasive procedures to more complex open surgeries.

List of medications used to treat this disease

The most commonly used medications to treat patients with posterior urethral valves include:

• Antibiotics to treat urinary tract infections (eg, amoxicillin).
• Anti-inflammatory drugs to reduce inflammation (eg, ibuprofen).
• Catecholamines to improve urination in cases of bladder spasticity.

Surgical interventions significantly reduce the need for long-term drug therapy.

Disease monitoring

Monitoring of patients with posterior urethral valves includes regular check-ups, especially after surgical treatment. The prognosis depends on the degree of obstruction and the presence of concomitant disorders:

• Monitoring kidney function with ultrasound and laboratory tests.
• Evaluation of inflammatory processes and periodic assessment of deformities, if present.
• Timely intervention when complications such as hydronephrosis are detected.

Complications may include kidney failure and recurrent urinary tract infections.

Age-related features of the disease

Posterior urethral valves can present differently depending on the patient's age:

• In newborns: often detected immediately after birth during examination for abnormalities of the genitourinary system.
• In children and adolescents: Children may complain of regular infections, urinary retention, and other symptoms.
• Adults: May experience complications such as chronic pain or urinary incontinence due to previous medical conditions.

Therefore, an individual approach to treatment is important depending on the patient’s age and health condition.

Questions and Answers

• What causes posterior urethral valves? The cause remains unclear, but it is believed that both genetic and environmental factors may be involved.
• What are the main symptoms of the disease? The main symptoms include urinary retention, frequent urinary tract infections, enlarged bladder and possible abdominal pain.
• How is this disease treated? Treatment includes both drug therapy and surgery to correct the anomaly and restore normal urine flow.
• What is the prognosis for patients with this anomaly? The prognosis depends on the timeliness and quality of treatment, but many patients can lead a normal life after surgery.
• Can posterior urethral valves be prevented? There are currently no known methods of primary prevention, but medical monitoring during pregnancy can help identify abnormalities at an early stage.