After Henry Jacob Bigelow popularized the technique of litholapaxy in 1878, the mortality rate dropped from about 24% to 2.4%. However, other treatment techniques continued to produce a high level of mortality, especially among inexperienced urologists. In 1980, Dornier MedTech introduced extracorporeal shock wave lithotripsy for breaking up stones via acoustical pulses, and this technique has since come into widespread use. Etymology
The term renal calculus is from the Latin rēnēs, meaning "kidneys", and calculus, meaning "pebble". Lithiasis (stone formation) in the kidneys is called nephrolithiasis (), from nephro-, meaning kidney, + -lith, meaning stone, and -iasis, meaning disorder. A distinction between nephrolithiasis and urolithiasis can be made because not all urinary stones (uroliths) form in the kidney; they can also form in the bladder. But the distinction is often clinically irrelevant (with similar disease process and treatment either way) and the words are thus often used loosely as synonyms. Children
Although kidney stones do not often occur in children, the incidence is increasing. These stones are in the kidney in two thirds of reported cases, and in the ureter in the remaining cases. Older children are at greater risk independent of whether or not they are male or female.As with adults, most pediatric kidney stones are predominantly composed of calcium oxalate; struvite and calcium phosphate stones are less common.
The main reason for this is that, compared with CT, renal ultrasonography more often fails to detect small stones (especially ureteral stones) and other serious disorders that could be causing the symptoms.On the contrary, a 2014 study suggested that ultrasonography should be used as the initial diagnostic imaging test, with further imaging studies be performed at the discretion of the physician on the basis of clinical judgment, and using ultrasonography rather than CT as an initial diagnostic test results in less radiation exposure and equally good outcome. Laboratory examination
Laboratory investigations typically carried out include
microscopic examination of the urine, which may show red blood cells, bacteria, leukocytes, urinary casts, and crystals;
urine culture to identify any infecting organisms present in the urinary tract and sensitivity to determine the susceptibility of these organisms to specific antibiotics;
complete blood count, looking for neutrophilia (increased neutrophil granulocyte count) suggestive of bacterial infection, as seen in the setting of struvite stones;
renal function tests to look for abnormally high blood calcium levels (hypercalcemia);
24 hour urine collection to measure total daily urinary volume, magnesium, sodium, uric acid, calcium, citrate, oxalate, and phosphate;
collection of stones (by urinating through a StoneScreen kidney stone collection cup or a simple tea strainer) is useful. Chemical analysis of collected stones can establish their composition, which in turn can help to guide future preventive and therapeutic management. Composition
Calcium-containing stones
By far, the most common type of kidney stones worldwide contains calcium.