Normal-range albuminuria does not exclude nephropathy in diabetic children
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Clinically detectable diabetic nephropathy (DN) begins with the development of microalbuminuria (MA). However, early renal dysfunction may be overlooked despite using that method. On the other hand, the gold standard in DN detection—that is, renal biopsy—is highly invasive. The aim of this study was to evaluate the level of neutrophil-gelatinase-associated lipocalin (NGAL) and interleukin (IL)-18 and their relations to albumin excretion rate (AER) in children with normal-range albuminuria, e.g. in those considered as not presenting diabetic nephropathy. The study group consisted of 22 children (age 12.7 ± 3.5 years) with type 1 diabetes mellitus (T1DM). Long-term glycemic control was assessed on hemoglobin A1c (HbA1c) levels (8.52 ± 1.78%). All patients presented normal estimated glomerular filtration rate (eGFR) (141 ± 23 ml/min/1.73 m2) and normal urinary albumin excretion (13.09 ± 7.63 mg/24 h). Fourteen healthy children served as a control group. Children with T1DM showed increased NGAL values with respect to controls—interestingly, both in serum (sNGAL) (867.43 ± 341.98 vs. 655.29 ± 196.17 ng/ml; p = 0.04) and in urine (uNGAL) (420.04 ± 374.16 vs. 156.53 ± 185.18 ng/ml, p = 0.04). IL-18 levels were not different in both groups both in serum (58.52 ± 20.11 vs. 69.79 ± 58.76 ng/ml; NS) and in urine (14.53 ± 12.74 vs. 14.60 ± 10.92 ng/ml; NS). Despite the relatively small study group, the positive correlation between sNGAL and AER was found [AER (mg/24 h) = 3.1893 + 0.01141 × sNGAL (ng/ml); r = 0.51; p = 0.014] as well as between uNGAL and AER [AER (mg/24 h) = 8.7538 + 0.01032 × uNGAL (ng/ml); r = 0.51; p = 0.016]. No relationship between sNGAL and uNGAL, and GFR and HbA1c were found. Normal-range albuminuria does not exclude diabetic nephropathy defined as increased sNGAL and uNGAL concentration. NGAL measurement can be more sensitive than MA and may become a useful tool for evaluating renal involvement in diabetic children.
KeywordsDiabetic nephropathy Biomarkers NGAL IL-18 Children
We thank Mrs. Milena Kornaszewska for her linguistic assistance and Marek Niedziela M.D., Ph.D for his kind contribution to improvement of our discussion.
- 7.Raile K, Galler A, Hofer S, Herbst A, Dunstheimer D, Busch P, Holl RW (2007) Diabetic nephropathy in 27, 805 children, adolescents and adults with type 1 diabetes: effect of diabetes duration, HbA1c, hypertension, dyslipidemia, diabetes onset and gender. Diabetes Care 30:2523–2528CrossRefPubMedGoogle Scholar
- 13.Trachtman H, Christen E, Cnaan A, Patrick J, Mai V, Mishra J, Jain A, Bullington N, Devarajan P, Investigators of the HUS-SYNSORB Pk Multicenter Clinical Trial (2006) Urinary neutrophil gelatinase-associated lipocalcin in D+HUS: a novel marker of renal injury. Pediatr Nephrol 21:989–994CrossRefPubMedGoogle Scholar
- 14.Suzuki M, Wiers KM, Klein-Gitelman MS, Haines KA, Olson J, Onel KB, O’Neil K, Passo MH, Singer NG, Tucker L, Ying J, Devarajan P, Brunner HI (2008) Neutrophil gelatinase-associated lipocalin as a biomarker of disease activity in pediatric lupus nephritis. Pediatr Nephrol 23:403–412CrossRefPubMedGoogle Scholar
- 22.Schultz CJ, Konopelska-Bahu T, Dalton RN, Carroll TA, Stratton I, Gale EA, Neil A, Dunger DB (1999) Microalbuminuria prevalence varies with age, sex, and puberty in children with type 1 diabetes followed from diagnosis in a longitudinal study. Oxford Regional Study Group. Diabetes Care 22:495–502CrossRefPubMedGoogle Scholar