Introduction

Renal colic is a medical condition characterised by severe, sharp, and often excruciating pain in the lower back or side (often located between the ribs and the hip). This pain is typically caused by the presence of kidney stones in the urinary tract and comes and goes in waves. Kidney stones, also known as renal calculi, are crystalline deposits that form within the kidneys and can obstruct the normal flow of urine. This condition often requires medical attention for pain relief and management.

Causes of renal colic

Kidney stones

The most common cause of renal colic is the presence of kidney stones.¹ These stones are composed of minerals and salts that accumulate in the urinary tract and can obstruct the flow of urine. The sharp pain occurs when a stone moves within the urinary system, causing irritation and pressure.

Ureteral obstruction

Besides kidney stones, other factors such as blood clots, tumours, or scarring in the ureters (the tubes that connect the kidneys to the bladder) can cause obstructions, leading to renal colic.

Urinary tract infections

In some cases, urinary tract infections can cause inflammation and swelling, which may lead to obstruction and pain.² 

Hydronephrosis

This condition occurs when the kidneys become swollen due to a backup of urine, often caused by a blockage in the urinary tract. 

Renal tumours

In rare cases, malignant or benign renal tumours can lead to symptoms mimicking renal colic, especially when they cause ureteral obstruction or restrict normal urinary flow.

Among these causes, kidney stones stand out as the most prevalent and well-documented causative factor. What are common causes associated with the development of kidney stones?  What complications and risks can arise from it and what are different lifestyle modifications which can help us avoid or manage this condition? Let us go through this information.

Risk factors of kidney stones

Diet 

• High intake of dietary calcium, oxalate-rich foods (spinach, beets and rhubarb), and sodium can increase the risk of kidney stone formation by promoting the crystallisation of minerals.
• Less water intake or dehydration leads to concentrated urine which also contributes to the stone formation process.
• Food rich in animal protein may lead to higher uric acid excretion and lower urine pH, elevating the risk of certain stone types, especially uric acid stones.
• Low consumption of citrate-rich foods, such as citrus fruits, may reduce the protective effect against stone formation by inhibiting crystal aggregation.

Genetics

Individuals with a family history of kidney stones may have a likelihood of forming stones. Certain genetic conditions, like cystinuria (a rare genetic condition in which stones made from an amino acid called cysteine form in the kidney, ureter, and bladder) directly increase the risk of stone formation by affecting the way the body processes and excretes minerals. Therefore, the presence of family history and genes make kidney stones more likely for an individual.

Dehydration

Although it has been mentioned earlier how important water intake is in kidney health, we should give hydration a separate title when discussing renal colic and kidney stone formation. Dehydration has been directly associated with renal stones. Low fluid intake leads to concentrated urine, which in the long run leads to supersaturation of minerals, ultimately leading to stone formation.³

Medical conditions

There are few medical conditions that increase the risk of kidney stones. These conditions include obesity, type 2 diabetes, inflammatory bowel disease, gout, hyperparathyroidism and repeated history of urinary tract infections. 

Drugs 

There are certain drugs which are also associated with a higher incidence of renal stone formation and consequently renal colic. Some examples of these drugs are diuretics, antiviral and antifungal drugs. Some antibiotics, such as ampicillin and cephalosporin, also have a higher propensity to cause renal stones if repeatedly used. People taking uncontrolled calcium/vitamin D supplements may also experience this phenomenon. Uricosuric drugs, which are used in gout, may also show renal stone formation as a side effect.⁴

Diagnosis and evaluation

The diagnosis of renal colic due to kidney stones typically involves clinical evaluation, imaging studies, and laboratory tests. Computed tomography (CT) scans are considered the gold standard for visualising kidney stones in judging their location and size. While other imaging techniques like ultrasound and intravenous pyelography (IVP) may also be utilised, CT scans offer higher sensitivity and specificity.

Laboratory tests to evaluate kidney function, blood chemistry, and analysis of urine help in assessing the impact of the obstruction on renal health. 

Signs and symptoms of renal colic

These symptoms may be a result of the intense discomfort experienced during an episode of renal colic

Characteristic pain of renal colic

Renal colic is severe and sudden in onset and in the region of the flank or lower back. It is colicky or spasmodic in nature. This pain may radiate to the groyne and lower abdomen.

Other common symptoms

Hematuria

The presence of blood in the urine which is often visible to the naked eye is called hematuria. It is common in renal colic due to irritation of the urinary tract by passing kidney stones.

Nausea and vomiting

Due to the severe pain and as a reflex response nausea and vomiting can accompany renal colic. These symptoms may be a result of the intense discomfort experienced during an episode of renal colic

Treatment options

Conservative management

Pain management

The primary goal in treating renal colic is pain management since renal colic is usually described as the worst pain. This is typically achieved with non-steroidal anti-inflammatory drugs (NSAIDs) and paracetamol or stronger pain medications such as opioids, depending on the severity of the pain.

Hydration

Increasing fluid intake can help flush out small kidney stones and prevent their formation. Adequate hydration is crucial for preventing recurrent kidney stones.

Medical expulsion therapy

In some cases, a healthcare provider may prescribe medications to help relax the muscles of the ureter, aiding in the passage of smaller kidney stones.

Interventional treatment

When kidney stones are too large or do not pass naturally, surgical procedures like shockwave lithotripsy, ureteroscopy, or percutaneous nephrolithotomy may be necessary to remove or break down the stones.

Treatment of underlying conditions

If renal colic is caused by factors other than kidney stones, such as urinary tract infections or ureteral obstructions, treatment will focus on addressing the underlying issue. 

Complications and risks

Obstructive complications

Hydronephrosis: Prolonged obstruction with renal calculi can lead to the swelling of the kidney (hydronephrosis), potentially causing kidney damage.

Kidney Damage: Severe or recurrent obstructions may lead to permanent kidney damage or renal failure.

Infection

Pyelonephritis: If a kidney stone blocks the flow of urine and bacteria enter the urinary tract, it can lead to a kidney infection (pyelonephritis).

Urinary tract infection (UTI): Obstructions can increase the risk of urinary tract infections (UTIs).

Recurrence of kidney stones

Recurrent stone formation can lead to repeated episodes of renal colic and potentially become worse over time. This may develop into chronic pain and may interfere with the day-to-day activity of an individual and compromise the quality of life.

Prompt diagnosis and appropriate management are essential to minimise these complications and risks associated with renal colic

Lifestyle modifications for prevention and management

Stay hydrated

Maintaining adequate fluid intake is one of the most effective ways to prevent kidney stones. Aim to drink at least 8-10 cups of water per day. According to the NHS drink 3 L of water to avoid recurrence of stone formation. Drinks like tea and coffee do also count. Adding fresh lemon juice is recommended if a person has already got a complaint about renal stones. 

Dietary adjustments

Reduce the consumption of high-oxalate foods like spinach, rhubarb, and beets, as oxalates can contribute to kidney stone formation.⁵

Excessive protein and salt intake can lead to kidney stone formation.⁶ A moderate intake of both can help reduce the risk. Avoid processed foods, canned soups, and fast food. Read food labels to monitor sodium content and choose low-sodium alternatives.

Another reason for avoiding high sodium is that it can increase the excretion of calcium in urine, which may contribute to kidney stone formation. Reducing sodium intake is essential.⁷

Remember that dietary modifications for kidney stone prevention should be personalised based on the type of stones one is prone to and a person’s overall health. Consult with a healthcare provider or a dietitian to create a dietary plan personalised to your specific needs and to monitor progress over time. Proper nutrition, combined with lifestyle changes, is a key component of preventing and managing renal colic due to kidney stones.

Regular exercise

Engage in regular physical activity to maintain a healthy weight and reduce the risk of kidney stone formation.

Control underlying medical conditions

If you have conditions like hyperparathyroidism or urinary tract infections, work with your healthcare provider to manage them effectively.

Alternative medicine

Traditional medicine systems 

In traditional medical systems such as Ayurveda and Traditional Chinese Medicine, healthcare practitioners offer holistic approaches to kidney stone prevention. These approaches may include specific dietary recommendations and herbal treatments.

Meditation and relaxation techniques

Stress and anxiety can exacerbate the perception of pain. Mindfulness meditation, yoga, and relaxation exercises can help patients manage stress and may indirectly improve their experience with renal colic.

Recognizing that the usefulness of alternative medicine in managing renal colic can vary from person to person, it is important to note that scientific evidence supporting many of these approaches may be limited or inconclusive. Conventional medical treatments, such as pain medications, fluid therapy, and surgical interventions, remain the primary methods for managing renal colic and kidney stones.

FAQs

What is the triad of renal colic?

The classic triad of symptoms associated with renal colic includes severe flank pain, hematuria (blood in the urine), and urinary urgency. This triad is indicative of an obstructing kidney stone or renal calculus causing the characteristic discomfort of renal colic

When does renal colic go away?

The duration of renal colic can vary, but it often resolves within a few hours to a few days. During this time period the body naturally passes the kidney stone. Medical intervention may be required if the stone is too large or causes complications.

What medicine is considered best for renal colic?

The best medication for renal colic pain is often a non-steroidal anti-inflammatory drug (NSAID) such as ibuprofen or ketorolac, which can help relieve pain.

Does drinking water help renal colic?

Yes, drinking water can be helpful in managing renal colic, especially if the cause is kidney stones. Adequate hydration can assist in flushing out small stones or promoting the passage of larger stones through the urinary tract, potentially reducing pain and discomfort. 

Summary

Renal colic, characterised by severe flank pain, is most commonly associated with kidney stones. However, it can also result from ureteral obstructions, urinary tract infections, hydronephrosis, and renal tumours. The diagnosis and treatment of renal colic depends upon the underlying cause, with kidney stones requiring a distinct approach, including pain management, stone removal, and preventive measures. Lifestyle modifications and medical interventions play a vital role in the management of renal colic across its different etiologies.