Investigation of Risk Factors for Nephrocalcinosis and Nephrolithiasis in Very Low Birth Weight and Preterm Infants under 32 Weeks at NICU

Document Type : Original Article

Authors

1 Department of Pediatrics, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran.

2 Department of Community Medicine, School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran.

3 School of Medicine, Ardabil University of Medical Sciences, Ardabil, Iran.

10.22038/psj.2026.92812.1511

Abstract

Introduction:
Nephrocalcinosis is a common complication in premature infants characterized by calcium deposition in the renal parenchyma. Multiple factors contribute to its development and it can lead to both short- and long-term complications. This study aimed to investigate the risk factors for nephrocalcinosis and nephrolithiasis in very low birth weight infants born before 32 weeks gestation at Alavi and Bu-Ali Hospitals in Ardabil.
Materials and Methods:
In this cross-sectional descriptive-analytical study, a total of 120 premature infants (30 cases and 90 controls) with gestational age less than 32 weeks or birth weight under 1500 g, admitted from April 2022 to August 2024, were assessed. Demographic characteristics, medications, blood and urine parameters, renal ultrasonography, and complications were evaluated. Statistical analysis was performed using Chi-square test, t-test, and multivariate logistic regression. Significance was set at p < 0.05.
Results:
Among 120 infants, 30 (25%) had nephrocalcinosis (cases), 12 (40%) of whom also had nephrolithiasis. Gestational age was lower in cases (26.16 ± 1.42 weeks vs. 28.95 ± 1.87 weeks, p < 0.001), birth weight was lower (907 ± 152 g vs. 1169 ± 187 g, p < 0.001), urine calcium-to-creatinine ratio > 0.8 (OR=8.45[CI:3.76-19.02]), family history of kidney disease (OR=5.12[95%CI:1.85-14.16]), mechanical ventilation > 10 days (OR=2.92[CI:1.71-4.99]), corticosteroid use (OR=3.21[CI:1.31-7.85]), and vancomycin use (OR=2.76[CI:1.14-6.67) were independent risk factors for nephrocalcinosis.
Conclusion:
Nephrocalcinosis is a relatively common complication in premature infants with multiple contributing risk factors. Identifying these risk factors helps in prevention, early diagnosis, and appropriate treatment.

Keywords

Main Subjects

References

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Journal of Patient Safety & Quality Improvement
Volume 14, Issue 2
April 2026
Pages 115-122

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