Effect of calcium intake on urinary oxalate excretion in calcium stone-forming patients

Effect of calcium intake on urinary oxalate excretion in calcium stone-forming patients

Autor Nishiura, José Luiz Autor UNIFESP Google Scholar
Martini, Lígia Araújo Autor UNIFESP Google Scholar
Mendonça, C.o.g. Autor UNIFESP Google Scholar
Schor, Nestor Autor UNIFESP Google Scholar
Heilberg, Ita Pfeferman Autor UNIFESP Google Scholar
Instituição Universidade Federal de São Paulo (UNIFESP)
Resumo Dietary calcium lowers the risk of nephrolithiasis due to a decreased absorption of dietary oxalate that is bound by intestinal calcium. The aim of the present study was to evaluate oxaluria in normocalciuric and hypercalciuric lithiasic patients under different calcium intake. Fifty patients (26 females and 24 males, 41 ± 10 years old), whose 4-day dietary records revealed a regular low calcium intake (<=500 mg/day), received an oral calcium load (1 g/day) for 7 days. A 24-h urine was obtained before and after load and according to the calciuria under both diets, patients were considered as normocalciuric (NC, N = 15), diet-dependent hypercalciuric (DDHC, N = 9) or diet-independent hypercalciuric (DIHC, N = 26). On regular diet, mean oxaluria was 30 ± 14 mg/24 h for all patients. The 7-day calcium load induced a significant decrease in mean oxaluria compared to the regular diet in NC and DIHC (20 ± 12 vs 26 ± 7 and 27 ± 18 vs 32 ± 15 mg/24 h, respectively, P<0.05) but not in DDHC patients (22 ± 10 vs 23 ± 5 mg/24 h). The lack of an oxalate decrease among DDHC patients after the calcium load might have been due to higher calcium absorption under higher calcium supply, with a consequent lower amount of calcium left in the intestine to bind with oxalate. These data suggest that a long-lasting regular calcium consumption <500 mg was not associated with high oxaluria and that a subpopulation of hypercalciuric patients who presented a higher intestinal calcium absorption (DDHC) tended to hyperabsorb oxalate as well, so that oxaluria did not change under different calcium intake.
Palavra-chave Calcium
Hypercalciuria
Hyperoxaluria
Kidney stones
Oxalate
Idioma Inglês
Data de publicação 2002-06-01
Publicado em Brazilian Journal of Medical and Biological Research. Associação Brasileira de Divulgação Científica, v. 35, n. 6, p. 669-675, 2002.
ISSN 0100-879X (Sherpa/Romeo, fator de impacto)
Publicador Associação Brasileira de Divulgação Científica
Extensão 669-675
Fonte http://dx.doi.org/10.1590/S0100-879X2002000600006
Direito de acesso Acesso aberto Open Access
Tipo Artigo
Web of Science WOS:000176452400006
SciELO S0100-879X2002000600006 (estatísticas na SciELO)
Endereço permanente http://repositorio.unifesp.br/handle/11600/1455

Exibir registro completo




Arquivo

Nome: S0100-879X2002000600006.pdf
Tamanho: 441.2KB
Formato: PDF
Descrição:
Abrir arquivo

Este item está nas seguintes coleções

Buscar


Navegar

Minha conta