Kidney Stones

Kidney stones are hard deposits made of minerals and salts that form inside the kidneys and may move through the urinary tract. They can cause severe flank pain, blood in the urine, nausea or urinary symptoms, but many stones can be treated safely once properly assessed.

Overview

Kidney stones, also called renal stones or urinary tract stones, are solid deposits that form when minerals and salts in the urine crystallize. They may stay in the kidney or move into the ureter, the narrow tube that carries urine from the kidney to the bladder. A stone can be as small as a grain of sand or large enough to block urine flow.

Stones do not always cause symptoms. Many small stones pass naturally with urine. However, when a stone moves, irritates the urinary tract or blocks the flow of urine, it can cause intense pain and other symptoms that need medical evaluation.

Kidney stones are a common urological condition and can affect adults of any age. Because the underlying cause may be related to hydration, diet, infection, medication, anatomy or metabolic factors, assessment by a qualified doctor helps guide both treatment and prevention.

Symptoms

Kidney stone symptoms often begin suddenly when a stone moves into the ureter or causes obstruction. The most typical symptom is severe pain in the side or back, below the ribs. This pain may travel toward the lower abdomen or groin and may come in waves as the urinary tract tries to move the stone along.

Other symptoms can include blood in the urine, cloudy or strong-smelling urine, burning during urination, frequent urination, urgency, nausea and vomiting. Some people feel restless and cannot find a comfortable position during a painful episode.

Symptoms may be different if a stone is associated with infection or if urine flow is significantly blocked. Warning signs include fever, chills, worsening weakness, persistent vomiting, inability to pass urine or severe pain that does not improve with medical care.

• Flank, back, abdominal or groin pain
• Pink, red or brown urine
• Painful or frequent urination
• Nausea or vomiting
• Fever or chills when infection is present

Causes & Risk Factors

Kidney stones form when the urine contains more crystal-forming substances than it can dilute. These substances may include calcium, oxalate, uric acid, phosphate or cystine. If urine volume is low, or if protective substances in the urine are reduced, crystals can grow into stones.

Several types of kidney stones exist, and knowing the type is important for prevention. Calcium-based stones are common, but stones may also be related to uric acid, recurrent urinary infections or inherited conditions that affect amino acid handling. A stone analysis, when available, can help identify the type.

Risk factors include not drinking enough fluids, living or working in hot environments, a personal or family history of kidney stones, recurrent urinary tract infections, certain digestive conditions, obesity, some metabolic disorders and anatomical problems that slow urine flow. Diet can also play a role, especially high salt intake or dietary patterns that increase stone-forming substances in the urine.

Not everyone with risk factors develops stones, and not all stones have a single clear cause. For people who have repeated stones, doctors may recommend a more detailed metabolic evaluation to look for preventable causes.

Diagnosis

Diagnosis begins with a medical history and physical examination. The doctor asks about the location and pattern of pain, urinary symptoms, fever, previous stones, medications, diet, fluid intake and family history. This helps distinguish kidney stones from other causes of abdominal, back or urinary pain.

Urine testing can show blood, infection, crystals or changes in acidity. Blood tests may assess kidney function, signs of infection and mineral levels. If a stone is passed, it may be collected and analyzed to identify its composition.

Imaging is often needed to confirm the stone and determine its size and location. Ultrasound can detect many kidney stones and signs of obstruction without radiation. CT scanning is highly accurate for many urinary stones and may be used when symptoms are severe, the diagnosis is uncertain or treatment planning requires precise information.

In some cases, additional imaging or functional assessment is needed, especially if there are repeated stones, a single functioning kidney, pregnancy, suspected anatomical abnormalities or reduced kidney function. The diagnostic approach is individualized to keep testing appropriate and safe.

Treatment Options

Treatment for kidney stones depends on the stone size, location, type, degree of obstruction, pain level, infection risk and overall kidney function. The right approach is decided by a urologist or kidney specialist after assessment. The goal is to relieve symptoms, protect kidney function, clear the stone when needed and reduce future risk.

Small stones may pass without a procedure, with medical supervision, adequate fluid intake and pain control. Doctors may also use medications to support symptom relief or help the ureter relax in selected cases. Patients should follow medical instructions and avoid delaying care if symptoms worsen.

When stones are unlikely to pass, cause repeated severe pain, block urine flow, affect kidney function or are associated with infection, a procedure may be recommended. Options can include shock wave treatment to break stones, endoscopic removal through the urinary tract, ureteroscopy with laser fragmentation or, for larger or complex stones, minimally invasive surgery through a small incision in the back.

If infection and obstruction occur together, urgent drainage of the kidney may be needed before definitive stone treatment. After treatment, follow-up imaging or urine testing may be recommended to confirm clearance and guide prevention. No single treatment is best for everyone; specialist evaluation is essential.

Living With / Prognosis

Most people recover well from a kidney stone episode, especially when the stone is treated promptly and kidney function is protected. Pain usually improves once the stone passes or the obstruction is relieved. Follow-up is important because stones can recur, and prevention is often as important as the initial treatment.

General prevention measures often include drinking enough fluids to keep urine diluted, reducing excess salt intake and following individualized dietary advice. Some patients may need specific recommendations based on stone type, urine chemistry or medical conditions. It is important not to make extreme dietary changes without guidance, because balanced nutrition remains necessary for overall health.

People with recurrent stones may benefit from keeping records of stone episodes, imaging results and laboratory findings. If a stone is passed, it should be saved if possible and given to the healthcare team for analysis. This information can make prevention more precise.

Acibadem International provides diagnosis and treatment for kidney stones through multidisciplinary specialists and JCI-accredited hospitals for international patients. As with any medical condition, the best care plan is based on an in-person assessment, test results and the patient’s individual needs.

When to See a Doctor

A doctor should evaluate any suspected kidney stone, especially if pain is severe, symptoms are new or there is blood in the urine. Even if a stone seems likely, imaging and urine tests may be needed to confirm the diagnosis and exclude infection or obstruction.

Urgent medical attention is needed if kidney stone symptoms occur with fever, chills, persistent vomiting, faintness, confusion, inability to pass urine or pain that cannot be controlled. These signs may indicate infection, dehydration or a blocked kidney, which require timely care.

People should also seek prompt evaluation if they have one kidney, known kidney disease, pregnancy, recurrent urinary tract infections, a history of complex stones or previous urological surgery. Early specialist care can reduce complications and help preserve kidney function.

Frequently asked questions

What are kidney stones?

Kidney stones are hard deposits of minerals and salts that form in the kidneys. They may remain in the kidney or move through the ureter toward the bladder. Symptoms occur most often when a stone moves or blocks urine flow.

What does kidney stone pain feel like?

Kidney stone pain is often sudden and severe, usually felt in the side or back below the ribs. It may move toward the lower abdomen or groin and may come in waves. Nausea, vomiting or urinary symptoms can occur at the same time.

Can kidney stones pass on their own?

Some small kidney stones pass naturally with urine. Whether this is safe depends on the stone size and location, pain level, infection risk and kidney function. A doctor can advise whether observation is appropriate or a procedure is needed.

How are kidney stones diagnosed?

Doctors diagnose kidney stones using medical history, physical examination, urine tests, blood tests and imaging. Ultrasound or CT scanning may be used to locate the stone and assess whether it is blocking urine flow. If a stone is passed, laboratory analysis can identify its type.

What treatments are available for kidney stones?

Treatment may include observation, symptom control, medication in selected cases, shock wave treatment, endoscopic stone removal or minimally invasive surgery. The best option depends on the stone and the patient’s overall condition. A specialist should decide the treatment plan after assessment.

How can kidney stones be prevented?

Prevention often begins with drinking enough fluids so the urine stays diluted. Depending on the stone type, doctors may recommend changes in salt intake, diet or medical management. People with recurrent stones may need urine and blood testing to identify specific risk factors.

When are kidney stones an emergency?

Kidney stones need urgent care if symptoms include fever, chills, persistent vomiting, inability to pass urine or severe uncontrolled pain. These may indicate infection, dehydration or a blocked kidney. Prompt treatment helps protect kidney function and overall health.

References

• European Association of Urology
• American Urological Association
• National Institute of Diabetes and Digestive and Kidney Diseases
• Mayo Clinic
• National Kidney Foundation

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.