Calculi

A calculus is a concretion of material (usually mineral salts) that forms in an organ or duct of the body. They may block the relevent duct causing pain, swelling and inflammation of the associated organ. more...

Aetiology

• From an underlying abnormal excess of the mineral, eg. with elevated levels of calcium (hypercalcaemia) that may cause kidney stones, dietary factors for gallstones.
• Local conditions at the site in question that promote their formation, e.g. local bacteria action (in kidney stones) or slower fluid flow rates, a possible explanation of the majority of salivary duct calculus occuring in the submandibular salivary gland.
• Bezoars are a type of calculus found in the intestines of mostly ruminant animals and may be composed of inorganic or organic constituents.

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