is a stone (a concretion
of material, usually mineral salts) that forms in an organ or duct of the body. Stones cause a number of important medical conditions.
Common stone diseases
A number of important medical conditions are caused by stones:
Stones can also be asymptomatic.
Some common principles (below) apply to stones at any location, but for specifics see the particular stone type in question.
Pathophysiology and symptoms
Stones can cause disease by several mechanisms:
- Irritation of nearby tissues, causing pain, swelling, and inflammation.
- Obstruction of an opening or duct, interfering with normal flow and disrupting the function of the organ in question.
- Predisposition to infection (often due to disruption of normal flow).
Diagnostic workup varies by the stone type, but in general:
- Clinical history and physical examination can be sufficient in some cases.
- Imaging studies are often needed.
- Some stone types (mainly those with substantial calcium content) can be detected on X-ray and CT scan.
- Many stone types can be detected by ultrasound.
- Factors contributing to stone formation (as in #Aetiology) are often tested:
- Laboratory testing can give levels of relevant substances in blood or urine.
- Some stones can be directly recovered (at surgery, or when they leave the body spontaneously) and sent to a laboratory for analysis of content.
Again, treatment varies by stone type, but in general:
- Modification of predisposing factors can sometimes slow or reverse stone formation.
- Medications can sometimes be used.
- Surgery is sometimes needed.
- Infections due to stones have to be treated with antibiotics and/or surgery.
- Pain is managed with medication.
The earliest operation for curing stones is also given in the Sushruta Samhita
(6th century BCE). The operation involved exposure and going up through the floor of the bladder.