ESPN 53rd Annual Meeting

ESPN 2021

Kidney Failure – an overlooked feature of Down Syndrome
Marieke S.E. CHATELION COUNET 1 Hans Pottel 2 Roos N. van der Plas 4 Michel Weijerman 3 Chantal J.M. Broers 4 Emil den Bakker 1 Arend Bökenkamp 1

1- Emma Children’s Hospital, Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Pediatric Nephrology, Amsterdam, The Netherlands
2- Department of Public Health and Primary Care, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium
3- Alrijne Ziekenhuis, Department of Pediatrics, Leiderdorp, The Netherland
4- Emma Children’s Hospital, Amsterdam UMC, Vrije Universiteit Amsterdam, Department of Pediatrics, Amsterdam, The Netherlands

OBJECTIVES: Life expectancy of children with Down syndrome (DS) has increased significantly in the last decades. DS is associated with a fourfold risk of urinary tract abnormalities, still data on renal dysfunction in DS patients are conflicting. The present study was set out to assess kidney function in a large pediatric tertiary DS clinic.

METHODS: Retrospective analysis of data collected during routine visits at the DS outpatient clinic of VU medical center. All patients aged between 2 and 18 years in whom serum creatinine had been measured were eligible for inclusion. Exclusion criteria were glucocorticosteroid use, neuromuscular disease or primary referral to a nephrologist or urologist. Kidney function was assessed using the full-age spectrum equations, i.e. FASheight (107.3/[sCr (mg/dL)/Q (Q = height-based median reference value)]) and FAScys= (107.3/sCys (mg/L)/0.82). In a subgroup of 74 patients, a total of 236 serial creatinine measurements with a minimum interval of 2 years were analysed by linear mixed modelling.

RESULTS: Creatinine was available in 189 patients (63% boys, aged 10.8 ± 5.0 years), cystatin C in 143 (64% boys). Mean FASheight was 83.6 ± 16.7 mL/min/1.73m2 and mean FAScys 87.3 ± 12.0 mL/min/1.73m2. Based on FASheight 32% of the patients had CKD stage I, 62% stage II and 6% stage III. There was no relation between kidney function and co-morbidity (i.e. celiac disease, congenital heart disease, hypothyroidism or history of leukemia). Serial measurements showed a significant decline of FASheight (slope -2.11 ml/min/1.73m2/year [95% CI -2.51 to -1.70], p < 0.0001).

CONCLUSION: Mildly to moderately impaired renal function is a common finding in children with Down syndrome. The progressive loss of GFR is troublesome and calls for regular monitoring of kidney function both in children and in adults with Down syndrome to identify potentially treatable risk factors for disease progression such as hypertension and microalbuminuria.