Urinary Calculi: Microbiological and Crystallographic Studies

Abstract

Although referred to as "urinary calculus disease", the formation of stone in the urinary tract is not caused by a single etiological agent. As such, diverse clinical investigations to diagnose the cause of stone formation must be carried out and the course of management after diagnosis must inevitably be different in each case. This review will cover all aspects of calculus formation, but will give particular attention to calculi caused by infection of the urinary tract with urease-producing bacteria. This is a recurrent, potentially life-threatening disease which has led clinicians to refer to the condition as "stone cancer". Because the etiology of infection stones is so different from stones caused by metabolic disorders, the two disease patterns should be considered separately, a fact often overlooked in epidemiological studies of stone formation. The importance of analysis of calculi as an aid to management is thus emphasized; identification of stone type will help to indicate appropriate therapy. A review of methods of analysis will be covered, particularly crystallographic analysis. Inhibition of bacterial urease as a means of management of infection stones will be discussed together with problems encountered and brighter hopes for the future.

GC-MS Analysis and Gastroprotective Evaluations of Crude Extracts, Isolated Saponins, and Essential Oil from Polygonum hydropiper L.

“…Proteus mirabilis is the most common pathogen concerned with stone formation (Rosenstein and Griffith, 1986 ). With alkalinization of urine, the soluble polyvalent ions become supersaturated and this happens when ammonia is released by microbial urease-catalyzed urea hydrolysis leading to crystallization and stone formation.…”

Microbial ureases: significance, regulation, and molecular characterization.

“…In humans, Proteuis inirabilis is the most common organism implicated in stone formation (193). Other urease-producing species associated with infection stones include Pseludomonas, Klebsiella, and Staphylococcus spp.…”

“…Urease-induced stones commonly manifest as matrix concretions in the renal pelvis, branched or staghorn renal calculi, or bladder calculi (72). Management strategy involves surgical removal or the use of high-energy shock waves to break up kidney stones in situ (lithotripsy), as well as administration of antimicrobial agents (193). Urease inhibitors such as acetohydroxamic acid or hydroxyurea have been shown to be beneficial postoperative chemotherapeutic agents (71,142).…”

Design, Synthesis, and Evaluation of Novel Organophosphorus Inhibitors of Bacterial Ureases

“…Ureolytic activity of several microorganisms, i.e., Proteus mirabilis, Proteus Vulgaris, and Ureaplasma urealyticum, is involved in the formation of urinary tract stones, which may lead to the chronic inflammation of kidney and its pelvis. [28][29][30][31] Additionally, urinary catheter obstruction in patients is caused by its colonization by urease-producing microorganisms, mainly P. mirabilis. 32,33 Moreover, the overproduction of ammonia by infectious microorganisms may contribute to ammonia encephalopathy or hepatic coma.…”