Diagnosis of<unk><unk> s is made on the basis of information obtained from the history, physical examination, urinalysis, and radiographic studies. Clinical diagnosis is usually made on the basis of the location and severity of the pain, which is typically colicky in nature (comes and goes in spasmodic waves). Pain in the back occurs when calculi produce an obstruction in the<unk> . Physical examination may reveal fever and tenderness at the costovertebral angle on the affected side. Imaging studies Calcium-containing<unk> s are relatively radiodense, and they can often be detected by a traditional radiograph of the abdomen that includes the<unk> s, ureters, and bladder (KUB film). Some 60% of all renal<unk> s are radiopaque. In general, calcium phosphate<unk> s have the greatest density, followed by calcium oxalate and magnesium ammonium phosphate<unk> s. Cystine calculi are only faintly radiodense, while uric acid<unk> s are usually entirely radiolucent. In people with a history of<unk> s, those who are less than 50 years of age and are presenting with the symptoms of<unk> s without any concerning signs do not require helical CT scan imaging. A CT scan is also not typically recommended in children. Otherwise a noncontrast helical CT scan with sections is the diagnostic method to use to detect<unk><unk> s and confirm the diagnosis of<unk> . Near all<unk> s are detectable on CT scans with the exception of those composed of certain drug residues in the urine, such as from indinavir. Where a CT scan is unavailable, an intravenous pyelogram may be performed to help confirm the diagnosis of urolithiasis. This involves intravenous injection of a contrast agent followed by a KUB film. Uroliths present in the<unk> s, ureters, or bladder may be better defined by the use of this contrast agent.<unk> s can also be detected by a retrograde pyelogram, where a similar contrast agent is injected directly into the distal ostium of the ureter (where the ureter terminates as it enters the bladder). Renal ultrasonography can sometimes be useful, because it gives details about the presence of hydronephrosis, suggesting that the<unk>  is blocking the outflow of urine. Radiolucent<unk> s, which do not appear on KUB, may show up on ultrasound imaging studies. Other advantages of renal ultrasonography include its low cost and absence of radiation exposure. Ultrasound imaging is useful for detecting<unk> s in situations where X-rays or CT scans are discouraged, such as in children or pregnant women. Despite these advantages, renal ultrasonography in 2009 was not considered a substitute for noncontrast helical CT scan in the initial diagnostic evaluation of urolithiasis. The main reason for this is that, compared with CT, renal ultrasonography more often fails to detect small<unk> s (especially ureteral<unk> s) 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. File:Kidney<unk> s abdominal X-ray.Bilateral<unk><unk> s can be seen on this KUB radiograph. There are phleboliths in the pelvis, which can be misinterpreted as bladder<unk> s. File:3mmstone.Axial CT scan of abdomen without contrast, showing a 3-mm<unk>  (marked by an arrow) in the left proximal ureter File:Ultrasonography of renal<unk>  located at the pyeloureteric junction.Renal ultrasonograph of a<unk>  located at the pyeloureteric junction with accompanying hydronephrosis. File:CT measurement of<unk><unk>  in soft tissue and bone window.Measurement of a 5.6 mm large<unk><unk>  in soft tissue versus skeletal CT window. Laboratory examination Struvite crystals found on microscopic examination of the urine 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<unk> s; * 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<unk> s (by urinating through a<unk> Screen<unk><unk>  collection cup or a simple tea strainer) is useful. Chemical analysis of collected<unk> s can establish their composition, which in turn can help to guide future preventive and therapeutic management. Composition<unk><unk>  type Population Circumstances Color Sensitivity Details Calcium oxalate 80% when urine is acidic (decreased pH) Black/dark brown 150 px Radio-opaque Some of the oxalate in urine is produced by the body. Calcium and oxalate in the diet play a part but are not the only factors that affect the formation of calcium oxalate<unk> s. Dietary oxalate is found in many vegetables, fruits, and nuts. Calcium from bone may also play a role in<unk><unk>  formation. Calcium phosphate 5–10% when urine is alkaline (high pH) Dirty white Radio-opaque Tends to grow in alkaline urine especially when proteus bacteria are present. Uric acid 5–10% when urine is persistently acidic Yellow/reddish brown Radiolucent Diets rich in animal proteins and purines: substances found naturally in all food but especially in organ meats, fish, and shellfish. Struvite 10–15% infections in the<unk>  and when urine is alkaline (high pH) Dirty white Radio-opaque Prevention of struvite<unk> s depends on staying infection-free. Diet has not been shown to affect struvite<unk>  formation. Cystine 1–2% rare genetic disorder Pink/yellow Radio-opaque Cystine, an amino acid (one of the building blocks of protein), leaks through the<unk> s and into the urine to form crystals. Xanthine Extremely rare Brick red Radiolucent Scanning electron micrograph of the surface of a<unk><unk>  showing tetragonal crystals of Weddellite (calcium oxalate dihydrate) emerging from the amorphous central part of the<unk>  (the horizontal length of the picture represents 0.5 mm of the figured original) Multiple<unk><unk> s composed of uric acid and a small amount of calcium oxalate A lenticular<unk><unk> , excreted in the urine Calcium-containing<unk> s By far, the most common type of<unk><unk> s worldwide contains calcium. For example, calcium-containing<unk> s represent about 80% of all cases in the United States; these typically contain calcium oxalate either alone or in combination with calcium phosphate in the form of apatite or brushite. Factors that promote the precipitation of oxalate crystals in the urine, such as primary hyperoxaluria, are associated with the development of calcium oxalate<unk> s. The formation of calcium phosphate<unk> s is associated with conditions such as hyperparathyroidism and renal tubular acidosis. Oxaluria is increased in patients with certain gastrointestinal disorders including inflammatory bowel<unk>  such as Crohn's<unk>  or in patients who have undergone resection of the small bowel or small-bowel bypass procedures. Oxaluria is also increased in patients who consume increased amounts of oxalate (found in vegetables and nuts). Primary hyperoxaluria is a rare autosomal recessive condition that usually presents in childhood. Calcium oxalate crystals can come in two varieties. Calcium oxalate monohydrate can appear as 'dumbbells' or as long ovals that resemble the individual posts in a picket fence. Calcium oxalate dihydrate have a tetragonal “envelope” appearance. Struvite<unk> s About 10–15% of urinary calculi are composed of struvite (ammonium magnesium phosphate, NH4MgPO4·6H2O). Struvite<unk> s (also known as "infection<unk> s," urease, or triple-phosphate<unk> s) form most often in the presence of infection by urea-splitting bacteria. Using the enzyme urease, these organisms metabolize urea into ammonia and carbon dioxide. This alkalinizes the urine, resulting in favorable conditions for the formation of struvite<unk> s. Proteus mirabilis, Proteus vulgaris, and Morganella morganii are the most common organisms isolated; less common organisms include Ureaplasma urealyticum and some species of Providencia, Klebsiella, Serratia, and Enterobacter. These infection<unk> s are commonly observed in people who have factors that predispose them to urinary tract infections, such as those with spinal cord injury and other forms of neurogenic bladder, ileal conduit urinary diversion, vesicoureteral reflux, and obstructive uropathies. They are also commonly seen in people with underlying metabolic disorders, such as idiopathic hypercalciuria, hyperparathyroidism, and gout. Infection<unk> s can grow rapidly, forming large calyceal staghorn (antler-shaped) calculi requiring invasive surgery such as percutaneous nephrolithotomy for definitive treatment. Struvite<unk> s (triple-phosphate/magnesium ammonium phosphate) have a 'coffin lid' morphology by microscopy. Uric acid<unk> s About 5–10% of all<unk> s are formed from uric acid. People with certain metabolic abnormalities, including obesity, may produce uric acid<unk> s. They also may form in association with conditions that cause hyperuricosuria (an excessive amount of uric acid in the urine) with or without hyperuricemia (an excessive amount of uric acid in the serum). They may also form in association with disorders of acid/base metabolism where the urine is excessively acidic (low pH), resulting in precipitation of uric acid crystals. A diagnosis of uric acid urolithiasis is supported by the presence of a radiolucent<unk>  in
Kidney stone disease
Urinary tract infection
Pyelonephritis
Glomerulonephritis
Piriformis syndrome
Pyonephrosis
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Nephritis