Kidney stones

Alternative Names

Renal calculi; Nephrolithiasis; Stones – kidney

Definition of Kidney stones

A kidney stone is a solid mass made up of tiny crystals. One or more stones can be in the kidney or ureter at the same time.

Causes, incidence, and risk factors

Kidney stones can form when urine contains too much of certain substances. These substances can create small crystals that become stones.

Symptoms

The main symptom is severe pain that starts suddenly and may go away suddenly:

Signs and tests

Pain can be severe enough to need narcotic pain relievers. The belly area (abdomen) or back might feel tender to the touch.

Treatment

The goal of treatment is to relieve symptoms and prevent further symptoms. (Kidney stones that are small enough usually pass on their own.) Treatment varies depending on the type of stone and how severe the symptoms are. People with severe symptoms might need to be hospitalized.

Expectations (prognosis)

Kidney stones are painful but usually can be removed from the body without causing permanent damage. They tend to return, especially if the cause is not found and treated.

Review

Louis S. Liou, MD, PhD, Assistant Professor of Urology, Department of Surgery, Boston University School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 1/14/2009

Kidney anatomy
Kidney - blood and urine flow
Nephrolithiasis
Intravenous pyelogram (IVP)
Lithotripsy procedure

ADAM Medical Encyclopedia

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