40 Although studies in children are limited, 1 prospective study showed that in children with distal ureteral calculi who were treated

with tamsulosin, there was a greater stone expulsion rate and decreased time to stone expulsion when compared with controls.41 Urine should be strained for several days to recover any gravel or calculi passed for analysis. Because UTIs often present concomitantly in children with calculi, a urine culture should be Onalespib nmr obtained and empiric antibiotic therapy initiated if a UTI is suspected. Fluid intake is a critical component of stone prevention by effectively reducing the concentration of lithogenic factors, including calcium, oxalate, uric acid, and cystine. Although high daily fluid intake reduces the risk of

recurrent stone formation,42 signaling pathway the exact prescription is unknown. Most clinicians recommend intake at least equal to calculated maintenance rates in children and no less than 2 to 2.5 L in adolescents and adults. Even higher fluid intake levels (1.5–2 L/m2) may be recommended for children with cystinuria or PH. Increased intake requirements may be required during periods of increased insensible water loss. Regarding fluids other than water, reports suggest that fluids that increase urinary pH and citrate excretion such as orange juice, lemonade, and black currant juice, as well as those that increase urinary volume such as coffee, tea, beer, and wine, reduce the risk of calcium stone formation.43 Conversely, grapefruit juices seem to increase the risk of calcium-based stones.43 and 44

Whether cola drinks increase SB-3CT lithogenic potential or not remains controversial.43 and 44 The association between sodium intake and calcium stone formation has been reported but has not been confirmed in all studies.44 Increased sodium intake is known to promote calciuria by competing for reabsorption at the level of the renal tubules. A low salt diet corresponding to less than 2 to 3 mEq/kg/d in children or less than 2.4 g/d in adolescents or adults is generally recommended for patients with hypercalciuria or calcium-containing stones. A low salt diet may also reduce urinary cystine excretion in patients with cystinuria. Until recently, higher calcium intake was thought to increase the risk of stone formation; however, there is substantial evidence now that a higher calcium containing diet is associated with a reduced risk of stone formation.45 A potential mechanism that might explain this paradox is that higher calcium intake effectively binds dietary oxalate in the gut, thereby reducing intestinal absorption and eventual urinary oxalate excretion.