Urinary Neutrophil Gelatinase-associated Lipocalin in the evaluation of Patent Ductus Arteriosus and AKI in Very Preterm Neonates: a cohort study

Abstract

BackgroundA patent ductus arteriosus (PDA) is frequently found in very preterm neonates and is associated with increased risk of morbidity and mortality. A shunt across a PDA can result in an unfavorable distribution of the cardiac output and may in turn result in poor renal perfusion. Urinary Neutrophil Gelatinase-associated Lipocalin (U-NGAL) is a marker of renal ischemia and may add to the evaluation of PDA. Our primary aim was to investigate if U-NGAL is associated with PDA in very preterm neonates. Secondary, to investigate whether U-NGAL and PDA are associated with AKI and renal dysfunction evaluated by fractional excretion of sodium (FENa) and urine albumin in a cohort of very preterm neonates.MethodsA cohort of 146 neonates born at a gestational age less than 32 weeks were consecutively examined with echocardiography for PDA and serum sodium, and urine albumin and sodium were measured on postnatal day 3 and U-NGAL and serum creatinine day 3 and 6. AKI was defined according to modified neonatal Acute Kidney Injury Network (AKIN) criteria. The association between U-NGAL and PDA was investigated. And secondly we investigated if PDA and U-NGAL was associated with AKI and renal dysfunction.ResultsU-NGAL was not associated with a PDA day 3 when adjusted for gestational age and gender. A PDA day 3 was not associated with AKI when adjusted for gestational age and gender; however, it was associated with urine albumin. U-NGAL was not associated with AKI, but was found to be associated with urine albumin and FENa.ConclusionsBased on our study U-NGAL is not considered useful as a diagnostic marker to identify very preterm neonates with a PDA causing hemodynamic changes resulting in early renal morbidity. The interpretation of NGAL in preterm neonates remains to be fully elucidated.

Risk factors and mortality rate in premature babies with acute kidney injury

“…It has been noted that the incidence of AKI varies between 3.4% and 71% in critical neonates admitted to the NICU . In our study, the incidence of AKI in premature babies was 20%, which was consistent with the previous studies.…”

“…The mortality of nonoliguric AKI patients ranges from 4.5%‐40%, compared to 25%‐78% for patients with oligo‐anuric AKI . In our study, the mortality rate in the group of preterm babies with oliguric AKI was high (46.2%) (Table ) and we detected that AKI was associated with increased risk of mortality similar to other studies …”

“…Acute kidney injury is frequent in very preterm babies and is associated with increased risk of morbidity and mortality, after adjustment for confounders, although outcomes in very preterm babies have improved over the past few decades . To adjust for likely mixers, we developed a binary logistic regression model to study potential risk factors associated with AKI in premature babies.…”

“…Many possible risk factors such as low GA, low BW, low Apgar scores at 1 and 5 minutes, male gender, SGA, low cord pH, intubation at birth, mechanical ventilation, umbilical artery/venous catheters, lower mean arterial pressures, congenital heart disease, perinatal depression, assisted ventilation, oliguria/anuria, exposure to various medications such as blood pressure medications (pressor/inotropic support), antenatal corticosteroids, ampicillin, ceftazidime, cefotaxime, gentamicin, vancomycin, ibuprofen treatment, and multiorgan failure including disseminated intravascular coagulation (DIC) and shock for the development of AKI in neonates have been clarified . When compared to term babies, premature babies are at more risk of developing AKI because they are exposed to various risk factors including prenatal fetal distress and postnatal other multiple risk factors such as perinatal asphyxia, IVH, sepsis, PDA, RDS, bronchopulmonary dysplasia (BPD), NEC, intrauterine growth retardation, placental insufficiency, pneumothorax, and various medications.…”

“…When compared to term babies, premature babies are at more risk of developing AKI because they are exposed to various risk factors including prenatal fetal distress and postnatal other multiple risk factors such as perinatal asphyxia, IVH, sepsis, PDA, RDS, bronchopulmonary dysplasia (BPD), NEC, intrauterine growth retardation, placental insufficiency, pneumothorax, and various medications. Furthermore, postnatal progression of preterm babies is usually problematic owing to the call for cardiovascular support, hypotension, and hypoxia . Moreover, to be only prematurity is an independent risk factor for AKI because of an insufficient nephrogenesis and low nephron count .…”