Clinical Report: Two-Year Renal Outcomes in Neonates With Nephrocalcinosis and BPD

Overview

In this single-centre retrospective case–control study of 308 premature infants weighing under 1500 g with bronchopulmonary dysplasia (BPD), nephrocalcinosis was identified in 205 (66.6%). At two years, nephrocalcinosis was not associated with haematuria or hypertension, while urinary tract infections (UTIs) were more frequent in the moderate/severe group than in the mild group. The study reports that moderate-to-severe nephrocalcinosis after discharge was associated with increased UTI risk.

Background

Nephrocalcinosis is a common renal finding in premature infants, with reported risk factors including lower gestational age, low birth weight and exposure to furosemide. It often resolves during early childhood, but potential short- and long-term renal consequences remain uncertain. Reported complications include UTIs and haematuria, while evidence regarding blood pressure and kidney function has been inconsistent. This study examined renal outcomes through age two in premature infants with BPD.

Data Highlights

Key Findings

• Nephrocalcinosis was present in two-thirds of the 308 premature infants with BPD in this single-centre cohort.
• Furosemide exposure was significantly more frequent among infants with mild nephrocalcinosis than among those without nephrocalcinosis (40.2% versus 24.3%; p=0.007).
• Gentamicin administration was more frequent in both nephrocalcinosis groups than in infants without nephrocalcinosis: 80.6% in moderate/severe disease and 75.1% in mild disease, versus 56.3% (reported p=0.010 and p=0.001, respectively).
• UTI incidence was higher in the moderate/severe group than in the mild group (36.4% versus 11.2%; p=0.004); the study abstract also reports increased UTI risk after discharge with moderate-to-severe nephrocalcinosis.
• Nephrocalcinosis was not associated with haematuria or hypertension; the study’s summary reports no effect on blood pressure or creatinine at two years.
• The study authors state that infants with nephrocalcinosis should be followed after birth for symptoms of UTI.

Clinical Implications

The study authors state that infants with nephrocalcinosis should undergo follow-up after birth for symptoms of UTI. The reported association between moderate-to-severe nephrocalcinosis and increased UTI risk supports attention to UTI symptoms during follow-up; the study did not find an association with haematuria or hypertension at two years.

Conclusion

In this cohort of premature infants with BPD, nephrocalcinosis was common and moderate-to-severe disease was associated with more UTIs than mild disease. Haematuria and hypertension were not associated with nephrocalcinosis at two years.

Related Resources & Content

1. Study authors, BMJ Paediatrics Open, year not provided — Two-Year Renal Outcomes in Neonates With Nephrocalcinosis and Bronchopulmonary Dysplasia: A Case–Control Study
2. Kidney care at NICU discharge and follow-up recommendations for preterm infants <34 weeks, Journal of Perinatology, 2026 — Kidney care at NICU discharge and follow-up recommendations for preterm infants
3. BMJ Paediatrics Open — Renal injury and hypocalcaemia in newborns with birth asphyxia at a tertiary care centre: a prospective observational study
4. Infection — The Presence of Extended-Spectrum Beta-Lactamase Producing Enterobacterales in Stool Cultures of Preterm Infants Does Not Correlate with Increased Risk of Necrotizing Enterocolitis: A 12-Year Retrospective Case-Control Analysis
5. Frontiers in Pediatrics — Assessing the Relationship Between Nucleated Red Blood Cell Count at Birth, Transfusion Volume, and the Development of Severe Bronchopulmonary Dysplasia
6. Frontiers in Pediatrics — Clinical characteristics and respiratory management of bronchopulmonary dysplasia in preterm infants: a retrospective case-control study
7. Kidney care at NICU discharge and follow-up recommendations for preterm infants <34 weeks
8. Kidney care at NICU discharge and follow-up recommendations for preterm infants<34 weeks - PMC
9. Toward a Harmonized Bronchopulmonary Dysplasia Definition: An International Delphi Process | Pediatrics | American Academy of Pediatrics
10. Kidney health outcomes in children born very prematurely compared to full-term counterparts: a systematic review and meta-analysis | Pediatric Nephrology | Springer Nature Link