The disease behind one of the most severe pains a person can experience.

Kidney stones or calculi are solid deposits of mineral, salts, or other materials that can obstruct the urinary tract. Although the pain experienced by an impacted kidney stone can become extremely intense, most of the stones are asymptomatic and can pass along urine without the patient noticing.

By the age of 70 years, up to 1 in 5 males and 1 in 10 females will have experienced a kidney stone at least once in their lives. Most calculi form without a clear immediate trigger, however, certain diseases, medications, dietary habits, low water intake, and excess body weight are known general risk factors. There are more specific conditions that predispose each type of renal stone:

• Calcium oxalate: Most common, usually idiopathic, but metabolic disorders, dietary supplemets, and bariatric surgery have been associated with an increased risk.
• Calcium phosphate: Some parathyroid and renal diseases.
• Uric acid: High intake of animal protein, chronic diarrhea, or metabolic diseases.
• Struvite: Urinary infections from certain types of bacteria.
• Cystine: A rare hereditary condition called cystinuria.

How do I know if I’m having a kidney stone?

Pain is the most predominant symptom. It can range from mild to very intense, and usually fluctuates in waves as the muscles of the urinary tract try to pass the stone. The most frequent location is below the ribs in the side, and/or back. Less likely, patients might experience red urine as the stone erodes the mucosa, making it bleed.

Kidney stones can be caused by or cause themselves urinary tract infections. In these cases, the patient may complain of foul smelling urine with a cloudy appearance, pain or a burning sensation while urinating, as well as generalized symptoms such as fever.

To avoid getting a kidney stone, drinking enough water, complying with a balanced diet, and maintaining a healthy weight are general measures that might help. There are other specific strategies and medications that a doctor might suggest according to each type of kidney stones.

What happens if I do get a kidney stone?

If a patient experiences any of the symptoms or has noticed gravel in their urine, they should go to their doctor. Most likely, an imaging study will be performed to determine the appropriate treatment, which can vary from at-home medication, to noninvasive or invasive procedures to evacuate the stone. These include shock waves that dissolve the stone, and direct stone removal through a transurethral or percutaneous approach.

References:
https://www.uptodate.com/contents/kidney-stones-in-adults-beyond-the-basics#H1
https://www.kidney.org/sites/default/files/moonstone-professional-education-teaching-card-final.pdf
https://www.mayoclinic.org/diseases-conditions/kidney-stones/symptoms-causes/syc-20355755