Kidneys and Ureters

The urinary system consists of the kidneys, which produce urine by filtering the blood, and two internal excretory ducts, the ureters, which transport urine to the bladder, where it is stored until excretion.

There are two kidneys, located in the posterior part of the abdomen on either side of the spine. They measure approximately 12 cm in height, 6 cm in width, and 3 cm in thickness. In cases of dysfunction, the kidneys shrink and decrease in size.

The kidneys are composed of three main parts :

• The calyces and renal pelvis are cavities that collect urine. Once produced by the nephrons, urine first accumulates in the calyces before passing into the renal pelvis and then into the ureters.
• The ureters are paired structures one left and one right. These are muscular and elastic ducts that propel urine through peristaltic movements, ensuring a steady flow from the kidneys to the bladder, where it is temporarily stored.
• The walls of the ureters are made up of three distinct layers, from outer to inner : the detrusor muscle (a layer of smooth muscle that contracts during urination), the lamina propria, and the urothelium.

The kidneys are vital organs that perform essential functions in the body. If one kidney becomes dysfunctional or diseased, the other can compensate for renal functions.

They have three primary roles :

• Their main function is to filter the blood and eliminate waste products such as urea, uric acid, creatinine, and medication residues, preventing the accumulation of toxins in the body.
• They produce several hormones, including erythropoietin (EPO), which stimulates red blood cell production in the bone marrow, as well as renin and angiotensin, which regulate blood pressure.
• The kidneys also contribute to the conversion of vitamin D into its active form, calcitriol. This process enhances calcium absorption in the intestines and its integration into bones, supporting bone health.

The kidneys can be affected by various conditions that impact their function. The main disorders treated by our team include :

Kidney Stones

Kidney stones are a relatively common condition, affecting approximately 10% of the population. They result from imbalances in urinary composition, leading to the formation of mineral deposits in the kidneys.

While often asymptomatic, these stones can cause severe pain when they move and attempt to pass from the kidney to the bladder via the ureters. This movement can trigger symptoms such as intense pain (renal colic), nausea, vomiting, or hematuria (blood in the urine).

Diagnosis is typically made through medical imaging. Treatment usually involves medication (anti-inflammatory drugs and pain relievers), but severe or complicated cases (such as those involving urinary tract infections or kidney failure) may require hospitalization or emergency surgical intervention.

Kidney Tumors

Kidney tumors are relatively rare compared to other urological cancers. They can be benign or malignant and result from the uncontrolled growth of kidney cells.

Kidney cancer most commonly develops from renal parenchymal cells and is associated with risk factors such as smoking, obesity, and prolonged dialysis.

Additionally, tumors affecting the kidney’s urinary tract (renal pelvis or ureter) are often linked to smoking and share characteristics similar to bladder cancer.

Kidney Malformations

Congenital kidney malformations are anatomical anomalies that can impact normal kidney function. These abnormalities may include agenesis, dysplasia, kidney duplication, or malrotation.

Such conditions can obstruct or restrict urine flow, leading to complications such as urinary tract infections and kidney stones. Diagnosis is typically made through medical imaging, and treatment depends on severity.

Some malformations require no intervention and are merely anatomical curiosities, while others may necessitate corrective surgery.

Severe cases can lead to kidney failure, requiring nephrological management, including dialysis or kidney transplantation.