Renal stone disease: causes, evaluation and medical treatment

Abstract

The purpose of the present review is to provide an update about the most common risk factors or medical conditions associated with renal stone formation, the current methods available for metabolic investigation, dietary recommendations and medical treatment. Laboratory investigation of hypercalciuria, hyperuricosuria, hyperoxaluria, cystinuria, hypocitraturia, renal tubular acidosis, urinary tract infection and reduction of urinary volume is based on the results of 24-hr urine collection and a spot urine for urinary sediment, culture and pH. Blood analysis for creatinine, calcium and uric acid must be obtained. Bone mineral density has to be determined mainly among hypercalciurics and primary hyperparathyroidism has to be ruled out. Current knowledge does not support calcium restriction recommendation because it can lead to secondary hyperoxaluria and bone demineralization. Reduction of animal protein and salt intake, higher fluid intake and potassium consumption should be implemented. Medical treatments involve the use of thiazides, allopurinol, potassium citrate or other drugs according to the metabolic disturbances. The correction of those metabolic abnormalities is the basic tool for prevention or reduction of recurrent stone formation. O propósito desta revisão é apresentar uma atualização sobre os fatores de risco ou condições médica comuns associadas com a formação de cálculos renais, os métodos atualmente disponíveis para investigação metabólica, recomendações dietéticas e tratamento médico. A investigação laboratorial para hipercalciúria, hiperuricosuria, hiperoxalúria, cistinúria, hipocitratúria, acidose tubular renal, infecção do trato urinário e redução do volume urinário, é baseada nos resultados das coleções de urina de 24h e amostra isolada para sedimento urinário, cultura e pH. Deve-se obter análises sanguíneas para creatinina, cálcio e ácido úrico. Deve-se determinar a densidade mineral óssea especialmente entre pacientes hipercalciúricos, e o hiperparatiroidismo primário deve ser excluído. O conhecimento atual não endossa as recomendações de restrição de cálcio, já que isto pode levar o hiperaxalúria secundária e desmineralização óssea. Redução da ingesta de proteína animal e de sal deve ser implementada junto com aumento da ingesta de líquidos e do consumo de potássio. Tratamento medicamentoso envolve o uso de tiazídicos, alopurinol, citrato de potássio ou outras drogas, conforme o distúrbio metabólico. A correção dessas anormalidades metabólicas é o instrumento básico para a prevenção ou redução da formação recorrente de cálculos.

The Association between Urinary Tract Infection and Idiopathic Hypercalciuria in Children

“…8 In recent studies, remarkable improvement has been observed in the majority of these clinical conditions with the treatment of IHC. [8][9][10][11][12][13][14][15][16] Since many of these conditions including UTI may also lead to significant morbidity and mortality in children, identification of IHC is of great importance.…”

Chemical and morphological analysis of kidney stones: a double-blind comparative study

“…The study of these layers, as conducted in the present morphological analysis, provides a better understanding of the genesis of individual stones. Knowledge of the origin of the stone and the factors involved in the lithogenic process is helpful when prescribing a diet or therapy intended to reduce the risk of recurrence 10,11 . Without treatment, the risk of recurrence of CaOx stones is 10% in one year, 33% in 5 years and 50% in 10 years 12 .…”

Study of lithogenic factors in men and women with recurrent nephrolithiasis in the north area of Almeria

“…La sobresaturación urinaria de diferentes metabolitos como el calcio, oxalato y úrico influye de manera positiva en la litogénesis, mientras que el aumento en orina de citrato y magnesio disminuye el riesgo de formación de litiasis al actual como inhibidores de la precipitación cristalina (11,12,13). Aunque la composición de la litiasis tiene en cierta manera que ver y se relaciona con las alteraciones metabólicas urinarias (7,14), es cierto que el análisis de los factores en sangre y orina es básico a la hora de establecer medidas profilácticas y preventivas.…”