SERUM NEUTROPHIL-GELATINASE ASSOCIATED LIPOCALIN AS A PREDICTOR OF POST-CONTRAST ACUTE KIDNEY INJURY IN CHILDREN By

Background: Post-contrast acute kidney injury (PC-AKI) is a decrease in renal function that follows intravascular administration of contrast media.


INTRODUCTION
The term PC-AKI is used to describe a decrease in renal function that follows intravascular administration of contrast media.The decrease in renal functions is usually mild, and renal function usually returns to baseline values within 1-3 weeks.Like all forms of acute kidney injury (AKI), an episode of PC-AKI is a marker for increased short-and long-term morbidity and mortality and prolonged hospital stay (van der Molen et.al., 2018).
Contrast media (CM) used in cardiac catheterization is a low osmolar non-ionic contrast media (Iohexol), which has less effect on cardiac function and fewer side effects than conventional ionic contrast media (McDonald et. al., 2018).
A new biomarker for AKI is NGAL, a 25 kDa siderophore binding protein composed of 179 amino acids, a member of the Lipocalin family, covalently attached to human neutrophil gelatinase, secreted by activated neutrophils.NGAL is involved in processes of cell-mediated immunity, bacteriostatic effects, cell proliferation, differentiation and apoptosis processes.It

AIM OF THE STUDY
This work aimed to assess the changes in serum NGAL level which serve as an early biomarker of PC-AKI in children with acyanotic congenital heart disease undergoing cardiac catheterization.

Ethical considerations:
Prior to conducting the study, the ethical approval of Ain Shams University ethical committee was obtained ensuring that the work complies with the principles of the Declaration of Helsinki in 1975.
Written informed consent was signed by caregivers before enrolment.All patients' data were kept confidential and care givers had the right to keep them.No conflict of interests existed regarding the research or the publications.No Funds were received to conduct the research.

Sample size:
The sample size estimation was done using the Epi Info7 program for sample size calculation, setting the confidence level at 95% and margins of error at 10% based on the work done by Padhy et. al (2014), a total of 30 patients was estimated to be sufficient sample size.

Patient population:
Inclusion criteria:

IV. Procedure:
• Cardiac catheterization via transfemoral approach was performed to all patients and a low osmolar non-ionic contrast media (Iohexol) was injected intra-arterial via catheters connected to power injector (Imaxeon-Avidia, Medrad, USA) with a pressure range from (400-800) psi and a rate range of 1-2 mL/kg/sec.

V. Postoperative follow up:
After the procedure children were monitored for any postoperative complications clinically and by laboratory evaluation.

Statistical analysis:
Analysis of data was done using Statistical Package for Social Science (IBM SPSS) version 23 (Chicago, IL, USA).Quantitative variables were described in the form of mean, standard deviation (SD) and range when parametric.Meanwhile median and interquartile range (IQR) when data found to be nonparametric.Qualitative variables were described as number and percentages.The comparison between quantitative data and parametric in two groups were done by Independent t-test , while in two paired groups paired t-test was used and in more than two paired groups Repeated Measure ANOVA test was used.Spearman correlation coefficients were used to assess the correlation between two quantitative parameters in the same group.

RESULTS
The results of the current study are displayed in the following tables: In the kidney, NGAL is mainly expressed in the loop of Henle and distal convoluted tubules.It's filtered by the renal glomeruli and reversibly reabsorbed in the proximal convoluted tubules (Andreucci et.al., 2016).

Table (
BSA: body surface area