Assessment of long-term renal complications in extremely low birth weight children

• Published in: Pediatric nephrology (Berlin, West) Vol. 26; no. 7; pp. 1095 - 1103
• Main Authors: Kwinta, Przemko, Klimek, Małgorzata, Drozdz, Dorota, Grudzień, Andrzej, Jagła, Mateusz, Zasada, Magdalena, Pietrzyk, Jacek Jozef
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-07-2011; Springer; Springer Nature B.V
• Subjects: Age Factors; Aging; Albuminuria - etiology; Analysis; Biomarkers - blood; Birth weight; Blood Pressure; Blood Pressure Monitoring, Ambulatory; Case-Control Studies; Chi-Square Distribution; Child; Children; Creatinine; Cross-Sectional Studies; Cystatin C - blood; Female; Gestational Age; Humans; Hypertension; Hypertension - etiology; Infant, Extremely Low Birth Weight; Infant, Newborn; Intensive care; Kidney - diagnostic imaging; Kidney Diseases - blood; Kidney Diseases - diagnostic imaging; Kidney Diseases - etiology; Kidney Diseases - physiopathology; Kidneys; Logistic Models; Male; Medicine & Public Health; Nephrology; Odds Ratio; Organ Size; Original; Original Article; Oxygen therapy; Pediatrics; Poland; Polish Americans; Premature babies; Premature birth; Respiratory distress syndrome; Risk Assessment; Risk Factors; Ultrasonic imaging; Ultrasonography, Doppler, Color; Urology; Poland; ABPM; Cystatin C; Blood pressure; Kidney volume; ELBW; Renal ultrasound; Microalbuminuria; Preterm
• ISSN: 0931-041X; 1432-198X
• DOI: 10.1007/s00467-011-1840-y

We assessed the long-term renal complications in a regional cohort of extremely low birth weight (ELBW) children born in 2002–2004. The study group, comprising 78 children born as ELBW infants (88% of the available cohort), was evaluated with measurement of serum cystatin C, urinary albumin excretion, renal ultrasound, and 24-h ambulatory blood pressure measurements. The control group included 38 children born full-term selected from one general practice in the district. Study patients were evaluated at a mean age of 6.7 years, and had a median birthweight of 890 g (25th–75th percentile: 760–950 g) and a median gestational age of 27 weeks (25th–75th percentile: 26–29 weeks). Mean serum cystatin C levels were significantly higher (0.64 vs. 0.59 mg/l;
p
 = 0.01) in the ELBW group. Hypertension was diagnosed in 8/78 ELBW and 2/38 of the control children (
p
 = 0.5). Microalbuminuria (>20 mg/g of creatinine) was detected only in five ELBW children (
p
 = 0.17). The mean renal volume was significantly lower in the ELBW group (absolute kidney volume 81 ml vs. 113 ml;
p
 < 0.001, relative kidney volume 85 vs. 97%;
p
 < 0.001). Abnormally small kidneys (<2/3 of predicted size) were detected in 19 ELBW and four control children (
p
 = 0.08). Multivariate logistic regression revealed that the only independent risk factor for renal complications was weight gained during neonatal hospitalization (odds ratio: 0.67; 95% confidence interval: 0.39–0.94). Serum cystatin C and kidney volume are significantly lower in school-age ELBW children. It is important to include systematic renal evaluation in the follow-up programs of ELBW infants.