Acute renal insufficiency in the neonatal intensive care unit

Longitudinal Changes in Serum Creatinine Levels and Urinary Biomarkers in Late Preterm Infants during the First Postnatal Week: Association with Acute Kidney Injury and Treatment with Aminoglycoside

We aimed to determine the incidence of acute kidney injury (AKI) and longitudinal changes in SCr levels and urinary biomarkers associated with AKI and aminoglycoside (AG) medication during the first week of life of late preterm infants. Urine biomarkers and SCr were measured in thirty late preterm infants on days one, two, five, and seven postnatal. Urine biomarkers included neutrophil gelatinase-associated lipocalin (NGAL), monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF), Tamm-Horsfall glycoprotein (THP), and liver fatty-acid-binding protein (L-FABP). Gestational age was positively correlated with SCr levels at birth, but inversely correlated with SCr levels at day five and day seven. Eighteen (60%) infants had stage 1 AKI, and twenty (67%) infants were treated with AGs. Infants with AKI had lower gestational age and lower birth weight than those without AKI. Urinary biomarkers adjusted according to uCr levels in infants with AKI were not statistically different from those in infants without AKI. There were no significant differences in incidence of AKI, and SCr levels during and after cessation of AG treatment. The uMCP-1/Cr ratio at days five and seven was higher in infants treated with AG than in non-treated infants.

Serum glutathione S-transferase Pi as predictor of the outcome and acute kidney injury in premature newborns

BACKGROUND

The incidence of acute kidney injury (AKI) among the neonates treated at the Neonatal Intensive Care Unit is high with high mortality rates. Glutathione S-transferase (GST) class Pi plays an important role in the protection of cells from cytotoxic and oncogenic agents. The aim of the study was to examine whether the levels of serum glutathione S-transferase Pi (GST Pi) determined after birth have any predictive value for the outcome and development of AKI in premature neonates.

METHODS

The prospective study included 36 premature neonates. The data about morbidity was gathered for all the neonates included in the study. The blood samples were taken in the first 6 h of life and GST Pi levels were measured.

RESULTS

The mean values and standard deviations of GST Pi among the neonates who died and who survived were 1.904 ± 0.4535 vs 1.434 ± 0.444 ng/ml (p = 0.0128). Logistic regression revealed a statistically significant, positive correlation between GST Pi levels and death (p = 0.0180, OR7.5954; CI 1.4148-40.7748).The mean value of GST Pi levels in the neonates with AKI was higher than in neonates without AKI (p = 0.011).

CONCLUSIONS

The conclusion of our study is that high levels of serum GST Pi in the first 6 h after birth are associated with an increased mortality and development of AKI in prematurely born neonates.

Incidence and outcomes of acute kidney injury in extremely-low-birth-weight infants

Background

Acute kidney injury (AKI) is a common event in the neonatal intensive care unit (NICU), especially in extremely-low-birth-weight (ELBW) infants. This cohort study investigated the incidence of and risk factors for AKI in ELBW infants and their overall survival at the postmenstrual age (PMA) of 36 weeks.

Methods

All ELBW infants admitted to our NICU between January 2010 and December 2013 were enrolled. Those who died prior to 72 hours of life, had congenital renal abnormality, or had only one datum of the serum creatinine (SCr) level after the first 24 hours of life were excluded. The criteria used for the diagnosis of AKI was set according to the modified neonatal KDIGO AKI definition.

Results

AKI occurred in 56% of 276 infants. Specifically, stage 1, stage 2, and stage 3 AKI occurred in 30%, 17%, and 9% of ELBW infants, respectively. High-frequency ventilation support (adjusted odds ratio [OR]: 3.4, 95% confidence interval [CI]: 1.78–6.67, p< 0.001), the presence of patent ductus arteriosus (adjusted OR: 4.3, 95% CI: 2.25–8.07, p < 0.001), lower gestational age (adjusted OR for gestational age: 0.7, 95% CI: 0.58–0.83, < 0.001), and inotropic agent use (adjusted OR: 2.6, 95% CI: 1.31–5.21, p = 0.006) were independently associated with AKI. Maternal pre-eclampsia was a protective factor (adjusted OR: 0.4, 95% CI: 0.14–0.97, p = 0.044). Infants with AKI had higher mortality before the PMA of 36 weeks with an adjusted hazard ratio (HR) of 5.34 (95% CI: 1.21–23.53, p = 0.027). Additionally, infants with stage 3 AKI had a highest HR of 10.60, 95% CI: 2.09–53.67, p = 0.004).

Conclusion

AKI was a very common event (56%) in ELBW infants and was associated with a lower GA, high-frequency ventilation support, the presence of PDA, and inotropic agent use. AKI reduced survival of ELBW infants before the PMA of 36 weeks.

Acute kidney injury in premature newborns-definition, etiology, and outcome

BACKGROUND

Neonatal acute kidney injury (AKI) is common and is associated with poor outcomes. New criteria for the diagnosis of AKI were introduced based on the increase in serum creatinine (SCr) levels and/or reduction of urine output (UOP). Yet, there is no generally accepted opinion so far, which criteria (whether SCr, UOP, or their combination) are the most appropriate to diagnose neonatal AKI.

METHODS

The retrospective study included 195 prematurely born neonates who fulfilled all inclusion criteria (with at least two SCr measurements). In all the neonates included in the study, AKI was diagnosed using three different definitions: (1) SCr criteria (an increase in SCr values of ≥0.3 mg/dl), (2) UOP criteria (UOP < 1.5 ml/kg/h), and (3) SCr + UOP criteria.

RESULTS

Out of all of the patients the study included, 85 (44%) were diagnosed with AKI. The neonates who had AKI had a significantly lower gestational age, birth weight, and Apgar score, longer duration of mechanical ventilation, and a higher mortality rate. SCr + UOP criteria showed higher sensitivity for prediction of death compared to SCr or UOP alone (p = 0.0008, 95% CI 0.040-0.154, and p = 0.0038, 95% CI 0.024-0.125, respectively). If only SCr or only UOP criterion are used, they fail to identify AKI in 61 and 67%, respectively. AKI was an independent risk factor for death (OR 7.4875; CI 3.1887-17.5816).

CONCLUSIONS

Similar to other studies, our data showed that neonates with AKI have worse outcome. Neonatal AKI defined based on SCr + UOP criteria is a better predictor of death than neonatal AKI defined based only on the SCr or UOP criteria. Also, by using SCr + UOP criteria for diagnosing neonatal AKI, more patients with AKI are recruited than when only one of those criteria is used.

Renal outcome in children born preterm with neonatal acute renal failure: IRENEO-a prospective controlled study

OBJECTIVES

Acute kidney injury (AKI) is a severe complication of prematurity, with currently unknown consequences for renal function in childhood. The objective of this study was to search for signs of reduced nephron number in children aged 3-10 years who had been born preterm with neonatal AKI and compare this group to control children.

METHODS

IRENEO was a prospective, controlled study conducted in 2013 in Nantes University Hospital. Children who were born at less than 33 weeks gestational age (GA) and included in the LIFT cohort were eligible for entry. Twenty-five children with AKI (AKI-C) and 49 no-AKI children were matched on a propensity score of neonatal AKI and age. AKI was defined as a serum creatinine level higher than critical values: 1.6 mg/dl (GA 24-27 weeks), 1.1 mg/dl (28-29) and 1 mg/dl (GA 30-32). Renal function was evaluated during childhood.

RESULTS

Mean age of the children at the time of the study was 6.6 years. No difference in microalbuminuria, estimated glomerular filtration rate (GFR) or pulse wave velocity was observed between the two groups. Renal volume was lower in the AKI-C group (57 vs. 68; p = 0.04). In the entire cohort, 10.8 % had a microalbuminuria, and 23 % had a diminished GFR (median 79 ml/min/1.73 m²). The GFR was lower in children with very low birth weight of <1000 g (99 vs. 107 ml/min/1.73 m²; p = 0.04).

CONCLUSION

In children born preterm, neonatal AKI does not seem to influence renal function. However, independent ofAKI, a large proportion of very preterm infants, especially those with very low birth weight, presented with signs of nephron reduction, thus requiring follow-up with a nephrologist.

Impact of healthcare-associated sepsis on mortality in critically ill infants

Healthcare-associated sepsis (HAS) is a life-threatening complication in neonatal intensive care. Research into the impact of HAS on mortality adjusted for comorbidities is however limited. We conducted a historical cohort study to evaluate impact of HAS on mortality stratified by birth weight and risk factors for mortality in the HAS cohort. HAS was defined according to the National Institute of Child Health and Human Development criteria. Logistic regression was used to calculate adjusted odds of mortality. Of 5134 admissions, 342 infants developed HAS (6.7 %). Mortality in the total and HAS cohort was 5.6 and 10.5 %, respectively. The majority of HAS was caused by commensals (HAS-COM, 59.4 %) and 40.6 % by recognized pathogens (HAS-REC). Adjusted for comorbidities, "HAS-REC" is only a risk factor for mortality in newborns >1500 g (adjusted odds ratio [aOR] 2.3, confidence interval [CI] 1.1-4.9). Post-hoc analysis identified HAS-REC as an independent risk factor for mortality in infants with gastrointestinal disease (aOR 4.8, CI 2.1-10.8). "Renal insufficiency," "focal intestinal perforation," and "necrotizing enterocolitis" are independent risk factors for mortality in the HAS cohort (aOR 13.5, CI 4.9-36.6; aOR 7.7, CI 1.5-39.2; aOR 2.1, CI 1.0-4.7, respectively).

CONCLUSION

For very low birth weight infants (≤1500 g), several comorbidities overrule the impact of HAS on mortality. After adjustment for comorbidities, HAS-REC independently predicts in-hospital mortality in heavier infants and in those with gastrointestinal disease.

WHAT IS KNOWN

• The relationship between healthcare-associated sepsis and mortality is influenced by the causative pathogen and is confounded by comorbidities. • Research on impact of healthcare-associated sepsis on mortality adjusted for comorbidities is limited as well as research on independent risk factors for mortality in neonates with sepsis. What is New: • We included a large list of comorbidities and stratified risk by birth weight in order to assess the true effect of healthcare-associated sepsis on mortality. • Risk for mortality was calculated for commensal flora and for recognized pathogens as causative micro-organisms.

Urinary kidney injury molecule-1 rapid test predicts acute kidney injury in extremely low-birth-weight neonates

BACKGROUND

The new urinary and serum biomarkers are discovered and are being investigated. With them we can diagnose acute kidney injury (AKI) faster and more precisely and they also have a significant role in the outcome prediction.

METHODS

The study included 22 extremely low-birth-weight neonates who were hospitalized in the neonatal intensive care units. They were divided into two groups based on serum creatinine (SCr) level-with and without AKI. Detection and quantification of urinary kidney injury molecule-1 (uKIM-1) was done on the third day of life, using commercially available KIM-1 rapid test. Subsequently, measurements were repeated only in subjects who were diagnosed with AKI, at different values of SCr.

RESULTS

Logistic regression analysis showed that AKI is an independent risk factor for mortality. In a group of neonates with AKI, 50% of neonates administered the KIM-1 rapid test showed positive findings. KIM-1 rapid test was positive in patients with a wide range of SCr levels (range of 78.73-385 µmol/l), but all subjects had oliguria and died in the next 24 h.

CONCLUSION

KIM-1 is a significant predictor of death. On the other hand, our study failed to prove that KIM-1 rapid test has any significance for early prediction of AKI.

Acute kidney injury in preterm infants admitted to a neonatal intensive care unit

BACKGROUND

The factors that contribute to the development of acute kidney injury (AKI) and treatment outcome among prematurely born neonates are not clearly understood.

METHODS

This retrospective study included 150 prematurely born neonates. AKI was defined as an increase of serum creatinine levels ≥0.3 mg/dl compared to basal values.

RESULTS

The majority of neonates with AKI (94.8 %) had a body weight <1,500 g. Logistic regression analysis showed that the Apgar score in the 5th minute <5, serum lactate levels >5 on the first day of life, core body temperature <36 ºC on the first day of life, occurrence of sepsis, intracranial hemorrhage, necrotizing enterocolitis, patent ductus arteriosus, as well as a treatment with vancomycin or dopamine were independent risk factors for the development of AKI. After the groups of neonates with and without AKI were adjusted, the calculated risk ratio for a negative outcome of treatment (death) was 2.215 (CI 1.27-3.86) for neonates with AKI. Neonates with AKI had higher serum sodium levels in the third and fourth days of life.

CONCLUSIONS

AKI is associated with high mortality in preterm neonates. It is very important to identify, as quickly as possible, all infants who are at high risk of developing AKI.

Critical serum creatinine values in very preterm newborns

Background

Renal failure in neonates is associated with an increased risk of mortality and morbidity. But critical values are not known.

Objective

To define critical values for serum creatinine levels by gestational age in preterm infants, as a predictive factor for mortality and morbidity.

Study Design

This was a retrospective study of all preterm infants born before 33 weeks of gestational age, hospitalized in Nantes University Hospital NICU between 2003 and 2009, with serum creatinine levels measured between postnatal days 3 to 30. Children were retrospectively randomized into either training or validation set. Critical creatinine values were defined within the training set as the 90^th percentile values of highest serum creatinine (HSCr) in infants with optimal neurodevelopmental at two years of age. The relationship between these critical creatinine values and neonatal mortality, and non-optimal neural development at two years, was then assessed in the validation set.

Results and Conclusion

The analysis involved a total of 1,461 infants (gestational ages of 24-27 weeks (n=322), 28-29 weeks (n=336), and 30-32 weeks (803)), and 14,721 creatinine assessments. The critical values determined in the training set (n=485) were 1.6, 1.1 and 1.0 mg/dL for each gestational age group, respectively. In the validation set (n=976), a serum creatinine level above the critical value was significantly associated with neonatal mortality (Odds ratio: 8.55 (95% confidence interval: 4.23-17.28); p<0.01) after adjusting for known renal failure risk factors, and with non-optimal neurodevelopmental outcome at two years (odds ratio: 2.06 (95% confidence interval: 1.26-3.36); p=0.004) before adjustment. Creatinine values greater than 1.6, 1.1 and 1.0 mg/dL respectively at 24-27, 28-29, 30-32 weeks of gestation were associated with mortality before and after adjustment for risk factors, and with non-optimal neurodevelopmental outcome, before adjustment.

Predictors of mortality in out born neonates with acute renal failure; an experience of a single center

OBJECTIVE

To evaluate the incidence, etiology, outcome, and predictors of mortality in neonates with Acute Renal Failure (ARF) in an out born Neonatal Intensive Care Unit (NICU) of India.

METHODS

A retrospective analysis of case records of out born neonates, who had ARF at admission or developed ARF during NICU stay, from January to December 2011 (one year) was done.

FINDINGS

Out of the total 456 neonates admitted during the study period, 44 (9.6%) neonates with ARF (32 males, 12 females) were studied. Their mean gestational age, weight, and age at admission was 34.7±3.9 weeks, 2100±630 grams, and 2.1±6.3 respectively. Causes of ARF were pre-renal in 22 (50%), intrinsic renal failure in 16 (36.3%), and post-renal in six (13.6%). Oliguria was present in 29 neonates. Neonatal sepsis was the commonest cause of ARF, followed by perinatal asphyxia, respiratory distress syndrome, and genitourinary anomalies. ARF was present at admission in 37 neonates. The mortality rate was 15.9% (7/44). Thirty-seven (84%) were discharged with complete recovery of renal functions and followed for six months. Shock, oliguria, need for mechanical ventilation, and presence of disseminated intravascular coagulopathy (DIC) emerged as predictors of mortality in neonates with ARF.

CONCLUSION

The incidence and mortality rate of neonatal ARF were 9.6% and 15.9% respectively in our out born NICU. Neonatal sepsis was the commonest cause of ARF followed by perinatal asphyxia. Shock, oliguria, need for mechanical ventilation, and presence of DIC were associated with poor outcome.

[Acute renal failure in premature neonates]

BACKGROUND/AIM

Hemodynamic stress is the leading cause of acute renal failure (ARF) in premature neonates. Incidence of ARF in this population is between 8 and 24%. The aim of this study was to determine the frequence of presence of ARF in premature neonates, as well as its impact on their survival.

METHODS

A retrospective study of 114 premature neonates [(gestational age, GA less than 37 gestation weeks (gw)] admitted to the Intensive Care Unit (ICU) at the Pediatric Clinic, Institute of Child and Youth Healthcare of Vojvodina in 2007 was conducted. Serum creatinine, urea and bilirubine were determined on the 3rd day of life in 65 newborns who met inclusion criteria. ARF was diagnosed in 16 newborns (n = 16/65; 25%).

RESULTS

The premature neonates with ARF had significantly lower GA [<28 gw - 8/16 (50%) vs. 5/49 (10%); p < 0.05], birth weight (BW) (1265 g vs. 1615 g; p < 0.05) and systolic blood pressure (43.37 mm Hg vs. 52.7 mmHg; p < 0.05) than ones without ARF. Non-olyguric ARF was diagnosed in 62% of newborns with ARF (n = 10/16), while the rest had the olyguric type (n = 6/16; 38%). Twenty-five percent of premature neonates with ARF (n = 4/16) died in contrast to 10% of premature neonates without ARF (n = 5/49). ARF was treated conservatively in all but 3 cases when peritoneal dialysis was performed. Renal function has recovered completely in all of the survivors. In order to determine their predictivity in relation to ARF, following parameters were analyzed: GA, BW < 1500 g, presence of concomitant sepsis and intracranial hemorrhage grade III/IV. BW < 1500 g demonstrated the highest sensitivity (se 0.75), while GA < 28 gw, sepsis and intracranial hemorrhage grade III/IV showed high specificity (sp = 0.90, 0.89 0.88, respectively).

CONCLUSION

Acute renal failure frequently occurs in population of premature neonates and requires meticulous fluid and electrolyte balance, especially in the case of low birth weight and extreme immaturity.