Incidence and risk factors of acute kidney injury in preterm infants with growth restriction.

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Thesis Type: Expertise In Medicine

Institution Of The Thesis: Eskisehir Osmangazi University, TIP FAKÜLTESİ, DAHİLİ TIP BİLİMLERİ BÖLÜMÜ, Turkey

Approval Date: 2022

Thesis Language: Turkish

Student: AYCAN ÇELEBİ

Supervisor: Özge Aydemir

Abstract:

Çelebi, A. Incidence and risk factors of acute kidney ınjury in preterm infants with intrauterine growth restriction. Eskişehir Osmangazi University Faculty of Medicine, Thesis in Pediatrics, Eskişehir, 2022. Preterm infants are vulnerable to acute kidney injury (AKI) due to incomplete nephrogenesis, comorbid illnesses, and exposure to nephrotoxic agents. Intrauterine growth restriction (IUGR) caused by placental insufficiency is one of the most important causes of prematurity. The hemodynamic redistribution that IUGR infants experience during fetal life, affects renal perfusion. In this prospective cohort study, we aimed to assess the incidence and risk factors of AKI in IUGR and appropriate for gestational age (AGA) preterm infants separately by using urine output and serum creatinine or glomerular filtration rate based diagnostic criteria. We enrolled 119 preterm infants with a mean gestational age of 30⁺⁶±3 weeks and a birth weight of 1486±520g.  AKI was detected in 28.5% of the patients. The incidence of AKI was similar in IUGR and AGA preterm infants (26.8% and 30%, respectively).  It was observed that neonatal RIFLE is the most sensitive criterion in the diagnosis of AKI and it provides an advantage in the identification of primarly mild kidney injury. Low APGAR score, intubation in the delivery room, respiratory distress syndrome, hemodynamically significant patent ductus arteriosus, pulmonary and intraventricular hemorrhage increase the risk of AKI in IUGR and AGA preterms. Although the findings of severe placental insufficiency and hemodynamic redistribution on prenatal ultrasonography were twice as common in IUGR infants suffering AKI, the difference was not statistically significant. In multivariate logistic regression analysis, low gestational age and late sepsis were identified as independent risk factors for AKI. It was found that 53.4% of AKI attacks in preterms were caused by late sepsis, and 73.5% of preterms with AKI had a history of late sepsis. Mechanical ventilation duration and hospitalizations were longer, and bronchopulmonary dysplasia and mortality rates were higher in newborns with AKI. In conclusion, AKI is a common condition in preterms and is associated with increased morbidity and mortality. Neonatal RIFLE should be used to diagnose AKI in preterms since it allows risky infants to be identified at an early stage.

Key words: Acute kidney injury, intrauterine growth restriction, prematurity