Kidney stones are small, hard deposits formed from mineral and acid salts that crystallize within the kidney. They are one of the most common disorders of the urinary tract, varying in size from a grain of sand to a small pebble. A kidney stone can cause incontinence, though this is typically an indirect and temporary symptom. The stone’s movement and interaction with the urinary system can trigger changes leading to urinary urgency and, in some cases, urge incontinence. This leakage is a secondary symptom that usually resolves once the stone is passed or removed.
The Connection Between Stones and Bladder Irritation
The urinary tract is a continuous system, and many symptoms arise from a stone’s passage down the ureter, the narrow tube connecting the kidney to the bladder. As the stone travels toward the bladder, it often encounters the ureterovesical junction (UVJ). The UVJ is the narrowest part of the ureter, making it a common place for stones to become lodged.
When a stone reaches the ureter near the bladder, it causes significant tissue irritation. This irritation triggers nerve signals interpreted by the brain as a strong, sudden need to urinate, known as urinary urgency. Because the nerves supplying the lower ureter and the bladder share pathways, ureteral irritation mimics the sensation of a full bladder.
This intense urgency often leads to urge incontinence, the involuntary leakage of urine following an overwhelming urge to empty the bladder. The stone’s presence can also cause the bladder muscles to contract abnormally or spasm, contributing to difficulty holding urine. If a stone causes a partial blockage, the increased pressure and inflammation can exacerbate this bladder dysfunction. This leakage disappears once the obstruction or irritation is gone.
Recognizing Other Common Kidney Stone Symptoms
While urinary urgency and incontinence can be signs of a stone, the primary symptom is severe, fluctuating pain known as renal colic. This pain often begins suddenly and can be excruciating, typically starting in the flank or back region below the ribs. As the stone progresses down the ureter, the pain may shift toward the lower abdomen and groin area.
Another common sign is hematuria, or blood in the urine, which can be visible (pink, red, or brown) or only detectable under a microscope. This bleeding is caused by the stone’s abrasive movement against the urinary tract lining. People may also experience nausea and vomiting alongside the pain, as nerve signals from the kidney are linked to the digestive system.
If a kidney stone causes a complete blockage or is associated with a urinary tract infection, more serious symptoms occur. The presence of a fever or chills is a significant warning sign, indicating a potential infection requiring immediate medical attention. Other urinary symptoms, such as painful or burning urination and passing small amounts of urine frequently, can also accompany the pain.
Diagnostic Testing and Symptom Resolution
To confirm the presence and location of a kidney stone, a healthcare provider typically orders diagnostic tests. A urinalysis is often performed first to check for microscopic blood, signs of infection, or the presence of stone-forming crystals. Blood tests are standard to assess kidney function and measure levels of substances like calcium or uric acid.
Imaging tests are essential to visualize the stone and determine its size and position within the urinary tract. A non-contrast computed tomography (CT) scan is the most accurate and frequently used method for a quick diagnosis in acute pain cases. Ultrasound is another option, often used for pregnant individuals or children to avoid radiation exposure.
The resolution of incontinence and other symptoms depends on the stone’s removal or passage. Small stones, often less than five millimeters, may be managed with watchful waiting, pain medication, and medications to help relax the ureter. For larger stones, treatment options include:
- Extracorporeal shock wave lithotripsy (ESWL), which uses sound waves to break the stone into smaller fragments.
- Ureteroscopy, where a small scope is passed through the urinary tract to remove or break up the stone.
Once the stone has passed or been successfully treated, the irritation and obstruction are eliminated, and associated symptoms of urinary urgency and incontinence resolve.