Metabolic Evaluation of Patients With Recurrent Idiopathic Calcium Nephrolithiasis

Abstract

Abstracturines collected and the time passing after a stone event. Urines collected at weekends diÂer from those Background. Metabolic evaluation in recurrent idiopathic calcium renal stone-formers (RCSF ) was ana-of the week only by their lower volumes. Abnormalities of RF for calcium nephrolithiasis can be detected in lysed with respect to the following questions: (1 ) do three 24-h urines provide more diagnostic accuracy in 85.3% of RCSF, and HC is the most common RF both in male and female RCSF. the metabolic evaluation of RCSF than 1 or 2 urines?; ( 2) does time after stone event influence the diagnostic yield?; (3) is urine composition at weekends diÂerent Key words: hypercalciuria; hyperoxaluria; hypocitratufrom that at mid-week?; (4 ) what are the prevalences ria; idiopathic calcium nephrolithiasis; low urine of the most important risk factors (RF ) of idiopathic volume; metabolic evaluation calcium nephrolithiasis, i.e. low volume (LV ), hypercalciuria (HC ), hyperoxaluria ( HO), hyperuricosuria ( HU ), hypocitraturia (Hypo-Cit), and hypomagnesiuria ( Hypo-Mg)?; and (5 ) do male RCSF diÂer from Introduction females with respect to urinary RFs? Methods. Seventy-five RCSF (59 men, 16 women)Renal stone formation is a common disorder: up to collected three 24-h urines ( U1-3) while on free-choice 15% of the population will develop kidney stones over diet. To account for possible variations in lifestyle and a lifetime [1]. About 80% of all stones that are formed diet, U1 and U3 had to be collected midweek and U2 contain calcium, mainly in the form of calcium oxalate at a weekend.[2]. Since renal stone formation is the ultimate conResults. When considering all three urines together sequence of increased urinary supersaturation with ( U1+U2+U3 ), the number of RF abnormalities/ calcium salts and most therapeutic approaches focus patient was 2.8±0.1, higher than numbers of any on reducing supersaturation [3 ], metabolic evaluation combination of two urines or of any single urine (P= in clinical practice has primarily to consider risk factors 0.0001 for all comparisons). The number of RF abnorof increased urinary supersaturation. malities also rose with time after stone event, fromThe question whether all patients with nephrolithi-0.8±0.1 (range 0-4) in U1 to 1.1±0.1 (range 0-4) in asis, in particular those with a first renal colic, should U3 (P=0.011 vs U1). Whereas all other RF did not undergo thorough metabolic evaluation, has been change between collections, urine volume was lower in addressed by several authors. A meta-analysis of six U2 (1793±90 ml ) than in U1 ( 2071±97 ml, P=0.0001 large retrospective studies [4 ] concluded that, given vs U2) and U3 (1946±97 ml, P=0.046 vs U2). At the relatively low morbidity associated with a first least 1 abnormality was found in 85.3% of all RCSF, stone episode and the rather high risk of side-eÂects and multiple abnormalities occurred in 47%. The most with so-called specific therapy, single stone-formers frequent RF was HC ( 39%), followed by HO and LV should not un...

Evaluation and treatment of pediatric idiopathic urolithiasis?revisited

“…It seems likely that in both younger children and those with recurrent stone formation, greater emphasis might need to be placed on possible genetic disorders. Similarly, based on clinical and laboratory data, more extensive evaluation for metabolic abnormalities, including distal renal tubular acidosis, hyperparathyroidism, and hyperuricemia might be indicated in the young patient and the recurrent stone former [2,3,6,23]. One also needs to bear in mind that on rare occasions hypercalciuria may be combined with hyperuricosuria or cystinuria.…”

The Primary Stone Event: A New Hypothesis Involving a Vascular Etiology

“…21 Conversely, 24-hour urinary collection in many stone formers is normal for the factors currently analyzed. 22 Second, the majority of stones are unilateral. One would expect stones to form on both sides if the primary factor were an abnormality in the global urinary constituents.…”

Calcium oxalate stone disease: role of lipid peroxidation and antioxidants

“…The major risk factors for recurrence are suggested to be male sex, multiple and lower calyx stones, early onset, familial history, and complications after stone removal [109]. The majority of upper urinary stones are composed of calcium oxalate and calcium phosphate and usually occur in men, while most stones of magnesium and ammonium phosphate occur in the bladder, mostly in women [41,106].The principal causative factor for the formation of calcium salt stones is attributed to the supersaturation of precipitating salts. Decreased excretion of substances such as citrate, phosphate, pyrophosphate, or Urol Res (2002) 30: 35-47 …”