Acute kidney injury in neonates: from urine output to new biomarkers

Prediction of urine volume soon after birth using serum cystatin C

BACKGROUND

Urine volume is an important clinical finding particularly during the early neonatal period. Oliguria is not a sign of impaired renal function but also a predictive factor for various complications and prognoses. It has been postulated that serum cystatin C (S-CysC) is a more sensitive biomarker for renal function than serum creatinine (S-Cr) in both adults and children. The objective of the current study was to investigate whether urine volume during 24 h after birth can be predicted using S-CysC.

METHODS

The subjects were 87 infants. The average gestational age was 34.7 ± 2.9 weeks and the average birth weight was 2135 ± 614 g. Blood samples were obtained from either the umbilical cord or the peripheral veins or artery of the newborn at birth. Data regarding the amount of urine volume and fluid intake during the first 24 h of life, maternal S-Cr and S-CysC levels within 48 h before delivery, and neonatal S-Cr and S-CysC levels at birth were collected from the medical records.

RESULTS

A significantly positive correlation was observed between maternal and neonatal S-Cr levels (r = 0.84, p < 0.0001) but not between maternal S-Cr levels and neonatal S-CysC levels (r = -0.069, p = 0.52). A significant negative correlation was seen between neonatal S-CysC levels and urine volume (r = -0.47, p < 0.0001).

CONCLUSION

The present study findings indicate that it may be possible to use S-CysC levels at birth to predict urine volume during the first 24 h of life.

Urinary KIM-1 in children undergoing nephrotoxic antineoplastic treatment: a prospective cohort study

BACKGROUND

Acute kidney injury (AKI) is a significant complication in patients with cancer, and nephrotoxic drugs are among the most common causes of AKI. To date, there is no study evaluating the potential role of renal biomarkers in children receiving nephrotoxic chemotherapy.

METHODS

A prospective study was conducted in children receiving methotrexate (MTX) or platinum-based treatment. Urinary kidney injury molecule-1 (KIM-1) was measured 24 h after the initiation of the chemotherapy infusion, and serum creatinine (sCr) was measured prior to drug infusion and at 24, 48, 72, and 96 h, 1 and 2 weeks, and 3 months post-initiation of treatment.

RESULTS

A total of 64 children were evaluated, of whom 21 (32.8%) developed AKI. The majority had AKI stage 1 (n = 12, 57.1%) and only one developed AKI stage 3. Median values of urinary KIM-1 were higher in patients with AKI than in those without AKI [10.7, interquartile range (IQR) 1.6-17.9 vs. 4.3 (IQR 1.3-6.1) ng/mg creatinine; p < 0.01]. Urinary KIM-1 showed good discrimination for AKI in patients receiving nephrotoxic chemotherapy, with an area under the receiver operator characteristic curve for AKI up to 1 week later of 0.82 (95% confidence interval 0.66-0.95). Even when measured only 24 h after drug infusion, urinary KIM-1 still showed good discrimination to predict persistent renal impairment three months later.

CONCLUSION

Urinary KIM-1 measured 24 h after the start of drug infusion has the potential to detect early AKI in pediatric patients treated with MTX or platinum-class drugs.

Risk of gentamicin toxicity in neonates treated for possible severe bacterial infection in low- and middle-income countries: Systematic Review

OBJECTIVES

To assess the risk of gentamicin toxicity and potential number of neonates exposed annually to this risk, through treatment with WHO-recommended first-line antibiotics (gentamicin with penicillin) for the 6.9 million neonates with possible serious bacterial infection (PSBI).

METHODS

Systematic literature review and assessment of the evidence using Cochrane and GRADE criteria. Meta-analysis was undertaken for pooled estimates where appropriate.

RESULTS

Eleven studies (946 neonates) were included (nine randomised controlled trials and two prospective cohort studies). Six trials reported consistently measured ototoxicity outcomes in neonates treated with gentamicin, and the pooled estimate for hearing loss was 3% (95% CI 0-7%). Nephrotoxicity could not be assessed due to variation in case definitions used. Estimates of the number of neonates potentially affected by gentamicin toxicity were not undertaken due to insufficient data.

CONCLUSION

Given wider scale-up of outpatient-based and lower-level treatment of PSBI, improved data are essential to better assess the risks from neonatal gentamicin treatment without assessment of blood levels, to maximise benefit and reduce harm.

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 asphyxiated neonates admitted to a tertiary neonatal unit in Sudan

Acute kidney injury (AKI) is a recognized complication of birth asphyxia. Early recognition of AKI is important in asphyxiated neonates as it helps in early intervention and appropriate management. The aim of this study was to determine the pattern of AKI in asphyxiated neonates and its relation to the grade of Hypoxic Ischemic Encephalopathy (HIE). This was a prospective hospital based study, conducted in the neonatal intensive care unit (NICU) at Gafaar Ibn Auf Children's Specialized Hospital during the period between January 2013 and December 2013. A total of 85 full term asphyxiated neonates who were admitted in NICU and diagnosed as HIE were enrolled in this study. with 50 (58.8%) less than 7 days of age, 31(36.5%) between (8-15) days and 4(4.7%) between (16-28) days. Males were found to be more affected than females (58.9% and 41.1%) respectively. Spontaneous vaginal delivery was the mode of delivery in 48(56.4%), assisted vaginal delivery in 14(16.5%), emergency caesarian in 19(22.4%) and elective caesarian section in. Percentage of AKI in those babies was 54.1%(46). With 30(65%) from those had non-oliguric type. Ten babies (21.7%) had serum creatinine between (1.5 - 2mg/dl), 29 (63.04%) between (2 - 3mg/dl) and 7(15.22%) between (3-4mg/ dl). This means that the majority of patients presented in injury stage. Hyperkalemia was found in (37.6%), hyponatremia in (27.1%) and hypocalceamia in (25.8%). Most of the babies with AKI had stage (ii) HIE. All babies were treated conservatively and 4(8.6%) died. In conclusion AKI was observed to be a common complication in asphyxiated neonates.