Reduced citrate in urine and increased fasting excretion of calcium are abnormalities frequently reported in stone forming (SF) patients. Increased dietary acid (or reduced alkali) introduction or absorption may be a potential cause of both these pathological findings. To test this hypothesis, we studied 64 SF patients (32 with fasting hypercalciuria (FH) and 32 without FH (NFH)). After a basal evaluation for nephrolithiasis, while on a 500 mg calcium diet, they were evaluated for: (1) daily intestinal alkali absorption (IAA), by urinary electrolyte excretion; (2) basal concentrations of PTH, calcitonin (CT) and 1,25(OH)2-VitD; (3) oral calcium load for evaluation of changes in calcium and hydroxyproline urinary excretions; (4) intestinal calcium absorption (18 patients), with double curve analysis (stable Sr as tracer); and (5) changes in citrate excretion after an alkali load (50 mEq of a mixture of calcium gluconate, lactate and carbonate) in 10 patients. The results demonstrated: (1) FH stone formers had reduced citrate excretion and lower mean IAA levels than NFH stone formers; (2) FH stone formers also had higher bone resorption levels with lower PTH and higher CT levels; (3) IAA levels were related to both citrate excretion and bone turnover indices; and (4) the increases in citrate excretion after oral alkali load were strictly related to basal IAA values (index of alkali absorption and/or generation after oral load), demonstrating that a different absorptive capacity of alkali rather than a different dietary content may underlie these metabolic abnormalities.
Urinary citrate, bone resorption and intestinal alkali absorption in stone formers with fasting hypercalciuria / P. Messa, G. Mioni, L. Paganin, A. Cruciatti, P.L. Greco, D. Turrin. - In: SCANNING MICROSCOPY. - ISSN 0891-7035. - 8:3(1994), pp. 531-539.
|Titolo:||Urinary citrate, bone resorption and intestinal alkali absorption in stone formers with fasting hypercalciuria|
|Parole Chiave:||Intestinal alkali absorption; citrate; bone resorption; hydroxyproline; fasting hypercalciuria; calcitonin; parathyroid hormone; urolithiasis; intestinal calcium absorption; vitamin-D|
|Settore Scientifico Disciplinare:||Settore MED/14 - Nefrologia|
|Data di pubblicazione:||1994|
|Appare nelle tipologie:||01 - Articolo su periodico|