The Impact of Diet on Urinary Risk Factors for Cystine Stone Formation

Abstract

Despite the importance of dietary management of cystinuria, data on the contribution of diet to urinary risk factors for cystine stone formation are limited. Studies on the physiological effects of diet on urinary cystine and cysteine excretion are lacking. Accordingly, 10 healthy men received three standardized diets for a period of five days each and collected daily 24 h urine. The Western-type diet (WD; 95 g/day protein) corresponded to usual dietary habits, whereas the mixed diet (MD; 65 g/day protein) and lacto-ovo-vegetarian diet (VD; 65 g/day protein) were calculated according to dietary reference intakes. With intake of the VD, urinary cystine and cysteine excretion decreased by 22 and 15%, respectively, compared to the WD, although the differences were not statistically significant. Urine pH was significantly highest on the VD. Regression analysis showed that urinary phosphate was significantly associated with cystine excretion, while urinary sulfate was a predictor of cysteine excretion. Neither urinary cystine nor cysteine excretion was affected by dietary sodium intake. A lacto-ovo-vegetarian diet is particularly suitable for the dietary treatment of cystinuria, since the additional alkali load may reduce the amount of required alkalizing agents.

Genetic lithiasis: the contribution of infrared spectroscopy as a diagnostic tool

“…En ambos tipos de litiasis genéticas identificadas en este estudio, la presencia de cálculos y su eliminación no se asocia a una cura, en cambio existe una elevada posibilidad de recidivas constantes si no se realiza un diagnóstico oportuno y un manejo adecuado del paciente afectado, acarreando con ello una disminución en la calidad de vida, aumento de gastos en internación, y la necesidad de múltiples intervenciones quirúrgicas que puede contribuir al daño renal y a la necesidad de extirpación del riñón afectado (23,24) .…”

“…El tratamiento de la cistinuria se realiza mediante medidas aplicadas a la dieta y farmacológicas. El adecuado manejo de la dieta incluye la disminución del consumo de sal y alimentos que contengan aminoácidos metionina y cisteína y el aumento en la ingesta de líquidos, además, se emplean alcalinizantes urinarios como bicarbonato y citrato de forma a aumentar la solubilidad de la cistina, y en caso de que estas medidas no sean efectivas, es posible recurrir a medicamentos tales como la mercaptopropionilglicina o la D-penicilamina (4,(23)(24)(25) . Además, el seguimiento de los pacientes debe ser realizado de forma a verificar el cumplimiento del objetivo de las medidas aplicadas, mediante el examen de la orina buscando que el pH sea mayor a 6,5 y la evaluación de la cristaluria seriada investigando la presencia de cristales de cistina y la determinación del volumen cristalino global para cistina (VCG) donde la meta es lograr valores menores a 3000 µm 3 /mm 3 que se asocia a un bajo riesgo de recurrencia (26,27) .…”

Cystinuria: An Overview of Diagnosis and Medical Management

“… 35 In adults, recommended sodium intake is <2 g/day, whereas in children <1-1.5 meq/kg/day is recommended. 36 , 37 Reducing dietary protein intake can also decrease cystine excretion. 38 In adults, recommended daily protein intake is <1 g/kg (per ideal body weight).…”

“… 39 In addition to protein restriction, reducing the cysteine precursor methionine intake has also been shown to decrease cystine excretion. 34 , 37 Animal proteins such as fish, poultry, meat, and eggs contain high amounts of methionine; thus, patients can be recommended to consume mostly non-animal proteins. Reducing animal protein intake can have additional benefits such as increasing urinary pH that enhances cystine solubility.…”

Urine Crystallization in Heat Exposed Workers in Semarang City, Indonesia

“…Kristalisasi urine terjadi akibat dehidrasi manusia yang berlebihan (Alzeer & Al Otair, 2014). Cairan keringat yang relatif tinggi akan mempengaruhi keseimbangan dan konsentrasi cairan tubuh, sehingga cairan tubuh akan berkurang (mengalami dehidrasi) yang diikuti dengan konsentrasi dan pembentukan kristal urine, (Siener et al, 2021). Namun pada orang yang mengalami kelainan sistem metabolisme kristal urine menjadi salah satu biomarker bahwa urine terlalu jenuh.…”