The Clinical Features and Prognosis of Nephrocalcinosis in Preterm Neonates : A Single Center Study in Korea

다국어 초록 (Multilingual Abstract)

Purpose: Nephrocalcinosis (NC) is frequently observed in premature infants. Small-scale studies have suggested that NC adversely affects renal function; however, the etiologic factors are still unclear. This prospective observational study aimed to iden- tify the factors that influence the development of NC, through urine analysis.
Methods: In total, 99 preterm infants (gestational age <34 weeks) diagnosed with NC in the neonatal intensive care unit (NICU) from October 2010 to March 2014 were evaluated. Data regarding perinatal characteristics, respiratory support, total parente- ral nutrition (TPN), and use of nephrotoxic drugs were analyzed. After an ultrasono- graphic diagnosis of NC, the infants were subjected to biweekly urine tests along with ultrasonographic follow-ups until the resolution of NC, in the outpatient department.
Results: NC was diagnosed in 23% (99/432) of the preterm infants admitted to the NICU. Their median gestational age and birth weight were 28+3 (range:23+5-35+2) weeks and 1,120 (range: 560-1,950) g, respectively. NC was diagnosed an average of 26.4±2.8 (range: 2-82) days after birth, and the corrected gestational age at that time was 32.4± 2.0 weeks. Preterm infants with NC had hyperoxaluria (oxalate/Cr=4.1 [oxalate/Cr< 0.3]), and low urinary citrate levels (citrate/Cr=0.03 [citrate/Cr>0.51]). The follow-up rate was 52% (27/52) and symptoms in none of the infants had progressed to nephro- lithiasis. In the infants that were followed up, NC was resolved at a mean age of 7.7 (range: 2-32) months.
Conclusion: Our results suggest that hyperoxaluria is a significant risk factor for the development of NC.

참고문헌 (Reference)

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