Many kidney stones do not cause any symptoms at all and patients may be completely unaware that they have a stone. Even very large kidney stones may cause no symptoms.
It is important to understand that pain from kidney stones is usually the result of blockage in the ureter (tube between each kidney and the bladder). Stones are formed in the kidney and cause no pain until they move into the ureter where they cause a blockage to the passage of urine. As the kidney continue to produce urine, they end up swelling under pressure (hydronephrosis) if there is a blockage and it is this swelling which causes the pain.
When pain occurs from a stone causing a blockage in the ureter it is called renal colic. This is usually severe pain lasting minutes to hours felt in the loin area. The pain is only felt on the side of the blockage and can radiate (spread) to the side and front of the abdomen and also to the groin, testicle or labia. Renal colic may be very severe pain which many have described as worse than labour pains.
Kidney stones may cause other symptoms apart from pain. Here is a list of possible symptoms:
- No symptoms.
- Pain.
- Blood in the urine – may be visible or microscopic only.
- Urinary Tract Infections.
- Nausea or vomiting.
- Urinary symptoms – passing urine frequently, urgently with burning.
