Marine Trigolet1, Francesco Bonsante1,2, Jean-Pierre Guignard3, Jean-Bernard Gouyon2, Silvia Iacobelli4,5. 1. Néonatologie, Réanimation Néonatale Et Pédiatrique, CHU La Réunion, Site Sud, Saint Pierre, France. 2. Centre d'Études Périnatales de L'Océan Indien, Université de La Réunion, UR7388, Saint Pierre, France. 3. Lausanne University Medical School, CHUV-1011, Lausanne, Switzerland. 4. Néonatologie, Réanimation Néonatale Et Pédiatrique, CHU La Réunion, Site Sud, Saint Pierre, France. silvia.iacobelli@chu-reunion.fr. 5. Centre d'Études Périnatales de L'Océan Indien, Université de La Réunion, UR7388, Saint Pierre, France. silvia.iacobelli@chu-reunion.fr.
Abstract
BACKGROUND: Preterm infants have physiological proteinuria and values of urine protein to creatinine ratio (UPr/Cr) are higher compared to full-term infants during the first week of life. Few investigations explored the changes of proteinuria in very preterm infants (VPI, ≤ 31 weeks of gestation) older than a week, and it is unclear whether high and persistent proteinuria is associated with kidney injury in this population. This study aimed to (1) observe the changes of UPr/Cr during the first month of life in VPI and (2) describe clinical and biological variables associated with the changes of UPr/Cr. METHODS: Spot urine samples for UPr/Cr were collected on the first day of life (DOL1) and then on DOL2-3, DOL5-6, second week of life (WOL2), WOL3, and WOL4 in VPI cared for in a third-level NICU. We tested the relationship of UPr/Cr with perinatal variables and diseases. RESULTS: A total of 1140 urine samples were obtained for 190 infants. UPr/Cr values (mg/mmol) (median with interquartile) at DOL1, DOL2, DOL3, WOL2, WOL3, and WOL4 were, respectively, 191 (114-399), 226 (152-319), 225 (156-350), 282 (200-488), 308 (188-576), and 325 (175-664). At the multivariate analysis, lower gestational age (GA) and increasing postnatal age were the only variables significantly associated with higher UPr/Cr values (p < 0.001). There was wide intra- and interindividual variability in UPr/Cr, especially in infants with higher GA and clinical stability. CONCLUSIONS: In VPI, UPr/Cr is higher at lower GA and increases with advancing postnatal age. High persistent proteinuria is not associated with clinical and biological variables reflecting kidney injury during the first month of life. A higher resolution version of the Graphical abstract is available as Supplementary information.
BACKGROUND: Preterm infants have physiological proteinuria and values of urine protein to creatinine ratio (UPr/Cr) are higher compared to full-term infants during the first week of life. Few investigations explored the changes of proteinuria in very preterm infants (VPI, ≤ 31 weeks of gestation) older than a week, and it is unclear whether high and persistent proteinuria is associated with kidney injury in this population. This study aimed to (1) observe the changes of UPr/Cr during the first month of life in VPI and (2) describe clinical and biological variables associated with the changes of UPr/Cr. METHODS: Spot urine samples for UPr/Cr were collected on the first day of life (DOL1) and then on DOL2-3, DOL5-6, second week of life (WOL2), WOL3, and WOL4 in VPI cared for in a third-level NICU. We tested the relationship of UPr/Cr with perinatal variables and diseases. RESULTS: A total of 1140 urine samples were obtained for 190 infants. UPr/Cr values (mg/mmol) (median with interquartile) at DOL1, DOL2, DOL3, WOL2, WOL3, and WOL4 were, respectively, 191 (114-399), 226 (152-319), 225 (156-350), 282 (200-488), 308 (188-576), and 325 (175-664). At the multivariate analysis, lower gestational age (GA) and increasing postnatal age were the only variables significantly associated with higher UPr/Cr values (p < 0.001). There was wide intra- and interindividual variability in UPr/Cr, especially in infants with higher GA and clinical stability. CONCLUSIONS: In VPI, UPr/Cr is higher at lower GA and increases with advancing postnatal age. High persistent proteinuria is not associated with clinical and biological variables reflecting kidney injury during the first month of life. A higher resolution version of the Graphical abstract is available as Supplementary information.
Authors: Ronald J Hogg; Susan Furth; Kevin V Lemley; Ronald Portman; George J Schwartz; Josef Coresh; Ethan Balk; Joseph Lau; Adeera Levin; Annamaria T Kausz; Garabed Eknoyan; Andrew S Levey Journal: Pediatrics Date: 2003-06 Impact factor: 7.124
Authors: Lina Gubhaju; Megan R Sutherland; Rosemary S C Horne; Alison Medhurst; Alison L Kent; Andrew Ramsden; Lynette Moore; Gurmeet Singh; Wendy E Hoy; M Jane Black Journal: Am J Physiol Renal Physiol Date: 2014-06-04