Ureteral Stones: Symptoms, Types, Causes and Treatment

Ureteral stones, also known as ureteral calculi, are a prevalent and sometimes excruciating urological condition. These stones form or lodge in the ureter—the narrow tube connecting the kidneys to the bladder—and can cause a range of symptoms, complications, and require various treatment approaches. Understanding their symptoms, types, causes, and treatment options is essential for both patients and healthcare professionals. In this comprehensive guide, we synthesize the latest evidence to provide a clear overview of ureteral stones and how they are managed in clinical practice.

Symptoms of Ureteral Stones

Ureteral stones often announce themselves with dramatic symptoms, but the presentation can be surprisingly varied. Recognizing these symptoms early can make a significant difference in outcomes—both in terms of timely treatment and prevention of complications.

Symptom	Description	Frequency/Severity	Source(s)
Renal Colic	Sudden, severe flank pain	Very common, intense	1
Groin Pain	Pain radiating to lower abdomen/groin	Common, variable	1
Dysuria	Painful urination	Occasional, mild-moderate	1
Hematuria	Blood in urine	Frequent, visible/microscopic	1, 9
Urinary Frequency	Increased urge to urinate	Sometimes	1
Fever	May indicate infection	Less common, serious	1
Constipation	Rare, non-specific	Rare	3

Table 1: Key Symptoms

Pain as the Hallmark

The classic symptom of a ureteral stone is renal colic: a sudden, severe, cramping pain, usually starting in the flank (side of the lower back) and often radiating toward the lower abdomen or groin. The pain may come in waves and can be intense enough to cause nausea or vomiting. Groin pain and lower abdominal discomfort are common as the stone moves further down the ureter 1.

Bleeding and Urinary Symptoms

Hematuria—blood in the urine—is frequently reported, either seen with the naked eye or detected only under a microscope. The passage of the stone can irritate the lining of the urinary tract, leading to bleeding 1 9. Patients may also experience dysuria (painful urination) and increased urinary frequency, especially if the stone is located closer to the bladder 1.

Signs of Infection and Rare Symptoms

The presence of fever suggests a urinary tract infection, which is a serious complication and requires urgent medical attention 1. Occasionally, symptoms like constipation or vague abdominal discomfort may occur, especially in older adults or those with other health conditions 3.

Types of Ureteral Stones

Not all ureteral stones are created equal. Their composition influences not only their appearance but also their likelihood of recurrence, detection, and optimal treatment.

Type	Main Composition	Prevalence/Features	Source(s)
Calcium Oxalate	Calcium, oxalate	Most common (~61%)	1
Calcium Phosphate	Calcium, phosphate	Second most common (~15%)	1
Uric Acid	Uric acid	Third most common (~12%)	1
Matrix Stones	Protein-matrix, low mineral	Rare, often radiolucent	3

Table 2: Stone Types and Features

Calcium-Based Stones

The majority of ureteral stones are made of calcium, most frequently as calcium oxalate and less commonly as calcium phosphate. These stones are often visible on X-rays and CT scans. They are associated with metabolic factors and dietary habits 1.

Uric Acid Stones

Uric acid stones are the third most common type. They may be radiolucent—meaning they are not visible on standard X-rays—and are more likely in individuals with high uric acid levels, such as those with gout or certain metabolic disorders 1.

Matrix Stones: The Rare Outlier

Matrix stones are unusual, consisting predominantly of protein and very little mineral content. They are soft, sometimes yellow in color, and can be missed on imaging tests. Risk factors include female gender, chronic kidney disease, prior dialysis, and recurrent urinary tract infections 3.

Causes of Ureteral Stones

Why do some people develop ureteral stones while others do not? The answer lies in a combination of anatomy, metabolism, lifestyle, and sometimes, underlying medical conditions.

Cause	Description or Risk Factor	Importance/Note	Source(s)
Anatomic Abnormalities	Structural urinary tract issues	Increases risk	1
Family History	Genetic predisposition	Significant risk factor	1
Prior Stones	History of stone disease	High recurrence risk	1
Metabolic Syndrome	Includes obesity, diabetes, HTN	Major risk factor	1
Chronic Infection	Especially for matrix stones	Important in some types	3
Age and Gender	Older age, male > female (except matrix)	Demographic risk	1, 3
Medications	Certain drugs (e.g., diuretics)	Contributory	1
Chronic Renal Failure	Especially with dialysis	Matrix stone risk	3

Table 3: Common Causes and Risk Factors

Structural and Genetic Factors

Anatomic abnormalities of the kidney or ureter—such as strictures, kinks, or congenital malformations—can create pockets where stones are more likely to form or become lodged. Family history is a strong predictor: if a close relative has had stones, your risk increases substantially 1.

Metabolic and Lifestyle Contributions

Obesity, metabolic syndrome (including high blood pressure and diabetes), and older age are all associated with higher risk. Diets high in salt, animal protein, and oxalate-rich foods (like spinach or nuts) can contribute to stone formation 1.

Chronic Disease and Medications

Patients with chronic kidney disease, especially those on dialysis, are at increased risk for certain rare stone types (like matrix stones) 3. Some medications—such as diuretics, calcium supplements, or drugs that alter urine acidity—can also increase risk 1.

Infection-Related Stones

Chronic urinary tract infections, particularly with certain bacteria, can lead to the formation of stones, especially matrix stones. These stones may be soft and not always visible on imaging, complicating diagnosis 3.

Treatment of Ureteral Stones

Treatment for ureteral stones is highly individualized, depending on the stone's size, location, composition, and the patient's symptoms and overall health. Approaches range from conservative observation to advanced surgical techniques.

Treatment	Main Approach/Indication	Notable Benefits/Drawbacks	Source(s)
Observation & Fluids	Small, uncomplicated stones (<10 mm)	Non-invasive, safe	1, 8
Pain Management	NSAIDs, analgesics	Effective symptom relief	1, 8
Medical Expulsive Therapy (MET)	Alpha-blockers (e.g., tamsulosin)	Increases passage, esp. >5 mm	5, 6, 1
Shock Wave Lithotripsy (SWL)	Non-invasive stone fragmentation	Less effective distal stones	1, 7, 8
Ureteroscopy (URS)	Endoscopic removal/disintegration	Highly effective, some risks	7, 8
Ureteral Stents	Maintain drainage, prevent obstruction	May cause urinary symptoms	2, 9
Percutaneous Nephrolithotomy	Large/complex stones	Invasive, for select cases	1, 8
Surgical Interventions	Refractory/complicated cases	For strictures, failures	4, 8
Dietary & Lifestyle	Prevention, recurrence reduction	Crucial for long-term health	1, 8

Table 4: Main Treatment Approaches

Conservative Management: Observation and Pain Relief

Many small ureteral stones (<10 mm), especially those located distally, will pass spontaneously. Increased fluid intake is recommended to facilitate passage. Pain is managed with NSAIDs—nonsteroidal anti-inflammatory drugs are first-line due to their effectiveness 1 8.

Medical Expulsive Therapy (MET)

Alpha-blockers, such as tamsulosin, are used to relax the ureter and promote stone passage—a strategy called medical expulsive therapy. Evidence shows that alpha-blockers increase the likelihood of stone clearance (especially for stones >5 mm), reduce the time to passage, decrease pain episodes, and lower the risk of hospital admission and surgery. However, their benefit for stones ≤5 mm is limited, and there is a slight increase in adverse effects 5 6 1.

Minimally Invasive Interventions

When stones fail to pass or are too large, intervention is needed:

• Shock Wave Lithotripsy (SWL):
  • Uses external sound waves to fragment stones.
  • Best for proximal (upper) ureteral stones.
  • Less effective for distal (lower) stones compared to ureteroscopy 7 8.
• Ureteroscopy (URS):
  • A thin scope is passed through the urethra and bladder into the ureter.
  • Stones are visualized and removed or broken up with lasers.
  • URS is highly effective, especially for distal stones, and has a lower re-treatment rate compared to SWL 7 8.

Ureteral Stents

Stents are temporary tubes placed in the ureter to maintain drainage, relieve obstruction, and prevent complications. While they are helpful in certain situations, stents can cause discomfort, urinary symptoms (frequency, urgency, pain), and increase risk of infections and hematuria. Using smaller diameter stents may reduce symptoms, but stents do not always improve stone clearance rates 2 9.

Advanced and Surgical Approaches

For very large, impacted, or complicated stones, percutaneous nephrolithotomy (a minimally invasive surgical procedure) or open surgery may be required. Additionally, if stones cause ureteral strictures, surgical interventions such as ureteral re-implantation or endoscopic dilation may be necessary 4 8.

Prevention and Recurrence Reduction

After stone passage or removal, increasing fluid intake and dietary modifications (reducing salt, animal protein, and oxalate-rich foods) are key to preventing recurrence. In high-risk individuals, metabolic evaluation and tailored medical therapy may be recommended 1 8.

Conclusion

Ureteral stones are a common and impactful health concern, but advances in diagnosis and treatment have dramatically improved patient outcomes. Prompt recognition of symptoms, understanding the underlying stone type and cause, and choosing the right treatment strategy are essential steps for optimal care and long-term prevention.

Key Takeaways:

• Symptoms: Sudden flank/groin pain, hematuria, and urinary symptoms are hallmarks; fever signals infection and requires urgent care.
• Types: Most stones are calcium-based; rarer types like matrix stones present unique challenges.
• Causes: Risk factors include anatomic abnormalities, family history, obesity, metabolic syndrome, and chronic infection.
• Treatment: Ranges from observation and pain management, to medical expulsive therapy, minimally invasive procedures (SWL, URS), stenting, and surgery. Prevention relies on lifestyle and dietary changes.

With advances in medical expulsive therapy and minimally invasive procedures, most patients achieve full recovery. Ongoing research continues to refine these approaches, offering hope for even better outcomes in the future.