Introduction: Epidemiological data suggest that obesity was associated with increased risk of renal injury in children.
Objective: To assess urinary podocalyxin in obese children and adolescents as a marker of obesity related kidney disease (ORKD) compared to urinary albumin creatinine (A/C) ratio as the standard marker of glomerular injury.
Methodology: This case-control study included 64 obese children between 8 and 12 years old with long standing obesity (> 5 years duration) in addition to 34 healthy age and sex matched controls. Cases with diabetes mellitus, chronic illness, glomerulonephritis or other renal diseases as well as patients with endocrinal or genetic causes of obesity were excluded from the study. Study population were subjected to full history taking including age, sex, obesity onset and duration, feeding habits, dietary history, exercise, family history of obesity, type 2 diabetes mellitus, hypertension or renal diseases as well as thorough physical examination including anthropometry (weight, height, waist circumference, hip circumference, body composition), blood pressure assessment, pubertal staging, signs of insulin resistance as acanthosis nigricans. Urine samples for A/C ratio and podocalyxin were collected from study population as well as blood samples for assessment of serum creatinine and fasting lipid profile.
Results: The current study included 30 males and 34 females with mean age of 10.66 (± 1.69) years, mean birth weight of 3.15 (± 0.57) kg and mean duration of obesity of 7.9 (± 2.5) years. Family history was positive for obesity in 75%, T2D in 48.4%, hypertension in 42.2% and renal disorders in 10.9% within the study group. Most of the cases had normal renal function tests (95.3%). However, many patients had hypercholesteremia (85%), hypertriglyceridemia (92.2%). No statistically significant difference was found between cases and controls regarding urinary Podocalyxin (P =0.115). However, urinary A/C showed a statistically significant difference between both groups (P =0.021). No statistically significant correlation was detected between urinary podocalyxin and different study parameters. However, there was a statistically significant positive correlation between urinary A/C and weight SDS, BMI SDS, GFR as well as triglycerides. Obese children with microalbuminuria had a statistically significant higher waist-hip ratio and higher TG level compared to those with normal A/C ratio (P =0.034 & 0.018 respectively).
Conclusion: Urinary A/C ratio was increased in obese children and correlated significantly with BMI, GFR and TGs. On the other hand, urinary podocalyxin was not a sensitive marker of ORKD in children.
19 - 21 Sep 2019
European Society for Paediatric Endocrinology