Urinary tract stones, including kidney and ureteral stones, may develop without causing noticeable symptoms. This is particularly common when a stone remains in the kidney and does not obstruct urine flow. Some people discover kidney stones incidentally during a routine health check-up, ultrasound, or computed tomography (CT) scan performed for another reason.
So, what are the symptoms of urinary tract stones?
Symptoms often become more noticeable when a stone moves from the kidney into the ureter and obstructs urine flow. This can increase pressure within the urinary tract and cause severe pain.
Common Symptoms of Urinary Tract Stones
Symptoms may vary depending on the stone’s size, location and movement. Common symptoms include:
- Severe or intermittent flank pain
- Pain that radiates to the lower abdomen or groin
- Blood in the urine
- Frequent or painful urination
- Nausea and vomiting
- Sweating or paleness associated with severe pain
- Fever or chills, particularly when an infection is present
1. Severe Flank or Lower Back Pain
One of the most common symptoms of a ureteral stone is sudden, severe pain in the flank or lower back. The pain may come in waves and can be extremely intense.
Some patients are unable to sit or lie still and may constantly change position or walk around trying to find relief. This pattern can differ from typical muscle or lower back pain, which may improve with rest.
As the stone moves down the ureter, the location of the pain may change.
- Stones in the kidney or upper ureter may cause pain in the flank or back.
- Stones in the lower ureter may cause pain that radiates to the lower abdomen, groin, testicle or labia.
A change in pain location does not necessarily mean that the stone has become larger. It may simply reflect the movement of the stone through the ureter.
2. Blood in the Urine
A urinary tract stone can irritate or scratch the lining of the urinary tract, causing blood to appear in the urine.
Some people may notice pink, red or brown urine, while others may have only a small amount of blood that can be detected through a urine test.
Clear-looking urine does not necessarily mean that the stone has passed. If symptoms continue or recur, medical evaluation may be necessary.
3. Nausea and Vomiting
Severe pain caused by a urinary stone can stimulate the autonomic nervous system, resulting in nausea, vomiting, sweating or paleness.
These symptoms may occur together with severe pain and may improve when the pain decreases or the underlying obstruction is treated.
4. Frequent or Urgent Urination
When a stone moves toward the lower ureter near the bladder, it may cause symptoms such as:
- Frequent urination
- Urinary urgency
- Small amounts of urine
- Lower abdominal discomfort
These symptoms can resemble a urinary tract infection. If no infection is found but symptoms persist, a doctor may recommend further evaluation for a stone near the lower ureter.
Does a Larger Kidney Stone Always Cause More Pain?
Not necessarily.
The severity of symptoms does not depend on stone size alone. A stone only a few millimeters in size can cause severe pain if it becomes lodged in the ureter and obstructs urine flow.
In contrast, a larger stone that remains in the kidney without causing obstruction may cause no symptoms at all.
For this reason, doctors cannot determine the severity of urinary stone disease based solely on pain intensity. The stone’s location and size, laboratory results and appropriate imaging studies may all be needed for an accurate assessment.
Can Kidney or Urinary Tract Stones Cause No Symptoms?
Yes.
Some stones, particularly those that remain inside the kidney without obstructing urine flow, may not cause any symptoms. As a result, patients may not know they have a stone until it is discovered during a routine health examination or an imaging test performed for another reason.
Therefore, the absence of symptoms does not necessarily rule out kidney or urinary tract stones.
When Should You See a Doctor Urgently?
Seek prompt medical attention if you experience any of the following:
- Severe flank or back pain that does not improve with pain medication
- Fever or chills together with urinary stone symptoms
- Persistent vomiting that prevents you from eating or drinking
- Very little urine or inability to urinate
- Significant blood in the urine or blood clots
- Severe pain when you have only one functioning kidney
- Urinary symptoms if you have chronic kidney disease
Severe pain accompanied by fever or chills, particularly when urinary flow is obstructed, may indicate an infection associated with obstruction and requires urgent medical treatment.
Summary: Urinary Tract Stone Symptoms
Urinary tract stones may cause no symptoms, particularly when a stone remains in the kidney without obstructing urine flow. When a stone moves into the ureter, it may cause severe flank or lower back pain, pain radiating to the lower abdomen or groin, blood in the urine, nausea, vomiting or frequent urination.
The severity of pain does not always reflect the size of the stone. If you experience severe pain, inability to urinate, or fever and chills together with urinary symptoms, seek medical attention promptly for appropriate diagnosis and treatment.
Next article: Learn how urinary tract stones are diagnosed, including urine tests, ultrasound and computed tomography (CT), and how doctors determine which imaging test is appropriate for each patient.
