Urinary Calculi

Back to Library

Urinary calculi may form anywhere in the lower urinary tract (urolithiasis).
the most common sites being the pelvicalyceal system and bladder.
The two main predisposing factors for stone formation are increased concentration of solute in urine (low fluid throughput or primary increase in metabolite), and reduced solubility of solute in urine
(due to persistently abnormal urinary pH).

Conditions that cause these factors to operate are low fluid intake, urine stasis, persistent
urinary tract infection, and primary metabolic disturbances.

The most common urinary stones, accounting for 80% of cases, are composed of calcium oxalate
or phosphate. Half of these cases are associated with idiopathic hypercalciuria, with only about
10% being caused by hypercalcaemia.

Other cases may be caused by hyperoxaluria, which has several associations, e.g. inflammatory
bowel disease. The second most common type of calculi, accounting for 15% of cases,
are those composed of magnesium, ammonium, and calcium phosphates (struvite).
They are associated with infection in the lower urinary tract as a result of urea-splitting
organisms, which make urine permanently alkaline.
Uric acid stones account for about 5% of cases and are predisposed by conditions causing
hyperuricaemia, e.g. gout. However, 50% of patients with uric acid stones do not have
hyperuricaemia, and it is suggested that production of persistently acid urine
is the predisposing factor.

Cystine stones are rare, accounting for under 1% of cases. They are seen in heritable
tubular transport defects causing cystinuria.
Interested in translating health topics to somali language!

We give here simplified and accurate information about the disease Info@somalidoc.com


DISCLAIMER: This website is provided for general information and it's run by medical students for medical students only and is not a substitute for professional medical advice. We are not responsible or liable for any diagnosis or action made by a user based on the content of this website. We are not liable for the contents of any external websites listed, nor do we endorse any commercial product or service mentioned or advised on any of the sites. Always consult your own doctor if you are in any way concerned about your health

Advertising | Conditions of use | Privacy policy | Webmaster
Copyright 2007 [
www.somalidoc.com]. All rights reserved.
Revised: 02-11-2014.