Association between glomerular filtration rate (measured by high-performance liquid chromatography with iohexol) and plasma oxalate

Abstract

IntRoductIonOxalate, the ionic form of plasma oxalate (POx), is an insoluble end-product of the metabolism of foods derived from various Association between glomerular filtration rate (measured by high-performance liquid chromatography with iohexol) and plasma oxalate Associação entre taxa de filtração glomerular (medida por cromatografia liquida de alto desempenho com iohexol) e oxalato plasmático Introdução: A hiperoxalemia secundária é uma doença multifatorial que afeta vários órgãos e tecidos em pacientes com rins nativos ou transplantados. O oxalato plasmático pode aumentar durante a insuficiência renal porque é eliminado do corpo pelos rins. No entanto, há evidências escassas sobre a associação entre taxa de filtração glomerular e oxalato plasmático, especialmente nos estágios iniciais da doença renal crônica (DRC). Métodos: uma casuística centrada na descrição das variações na apresentação clínica. Foi realizado um estudo piloto a partir da análise transversal com 72 indivíduos. ResumoPalavras-chave: Taxa de filtração glomerular; Hiperoxalúria; Doença renal crônica.

Assessment of Plasma Oxalate Concentration in Patients With CKD

“…This is in accordance with previous studies describing P Ox values of 1 to 3 mM in healthy adults 11,12,17 and an increase of P Ox when eGFR falls below 20 to 30 ml/min per 1.73 m 2 . 14,15 However, previous studies examining P Ox in CKD comprised only small cohorts (<80 patients) with the mean GFR being at least 14 ml/min per 1.73 m 2 higher than in our study. 14,15 By assessing P Ox in a large representative cohort (>1800 participants), we noted P Ox concentrations below 2 mM were not limited to CKD stages 1 to 3, but could also be found in a notable proportion of patients with an eGFR <30 ml/ min per 1.73 m 2 .…”

“…14,15 However, previous studies examining P Ox in CKD comprised only small cohorts (<80 patients) with the mean GFR being at least 14 ml/min per 1.73 m 2 higher than in our study. 14,15 By assessing P Ox in a large representative cohort (>1800 participants), we noted P Ox concentrations below 2 mM were not limited to CKD stages 1 to 3, but could also be found in a notable proportion of patients with an eGFR <30 ml/ min per 1.73 m 2 . In contrast to a recent study, 15 we could further demonstrate that P Ox concentrations >5 mM were not limited to eGFR levels < 30 ml/min per 1.73 m 2 , but also could be detected in some individuals with an eGFR of approximately 50 ml/min per 1.73 m 2 .…”

“…14,15 By assessing P Ox in a large representative cohort (>1800 participants), we noted P Ox concentrations below 2 mM were not limited to CKD stages 1 to 3, but could also be found in a notable proportion of patients with an eGFR <30 ml/ min per 1.73 m 2 . In contrast to a recent study, 15 we could further demonstrate that P Ox concentrations >5 mM were not limited to eGFR levels < 30 ml/min per 1.73 m 2 , but also could be detected in some individuals with an eGFR of approximately 50 ml/min per 1.73 m 2 . Such variations in P Ox results within a heterogeneous CKD cohort may have several reasons.…”

“…To date, only a few studies have investigated P Ox in the general CKD population, [14][15][16] which may be due to the complex preanalytical sample preparation. Based on our findings, we established a simplified standardized procedure for sample handling and applied it to P Ox measurement in 1826 patients with common forms of CKD.…”

“…[8][9][10] Whereas in healthy adults and children P Ox concentrations have been reported to be in the range of 1-5 mM, [11][12][13] an increase of P Ox is generally described in CKD. 9,14,15 However, a systematic assessment of P Ox as a function of eGFR is lacking.…”