Calculus (medicine)

Calculus
Other names	Stone
An 8-mm kidney stone
Symptoms	Pain
Complications	Inflammation
Prevention	Diet
Treatment	Drinking water, surgery

A calculus (pl.: calculi), often called a stone, is a concretion of material, usually mineral salts, that forms in an organ or duct of the body. Formation of calculi is known as lithiasis (/ˌlɪˈθaɪəsɪs/). Stones can cause a number of medical conditions.

Some common principles (below) apply to stones at any location, but for specifics see the particular stone type in question.

Calculi are not to be confused with gastroliths, which are ingested rather than grown endogenously.