MO1025: Periostin as a Potential Biomarker of Renal and Arterial Damage in Children with Tuberous Sclerosis Complex

Abstract BACKGROUND AND AIMS Experimental data suggest that periostin is involved in the formation of renal cysts. Tuberous sclerosis complex (TSC) is a multisystem genetic disease characterized by the formation of lesions in virtually all organs, including the kidney—most commonly angiomyolipomas (AML) and cysts. There are no reliable markers of progression of renal lesions in patients with TSC. The study aimed to evaluate serum periostin levels in children with TSC and to assess the usefulness of periostin as a marker of renal lesion severity and arterial damage in this group of patients. METHOD In a group of 35 children with TSC (mean age 8.46 ± 5.64 years, 17 boys, 18 girls), serum periostin levels (ng/mL), anthropometric parameters, renal changes (by ultrasound and magnetic resonance imaging), blood pressure and biochemical parameters were evaluated. The control group consisted of 25 healthy children (mean age 8.72 ± 4.73 years, 14 boys, 11 girls). In addition, central pressure and parameters of arterial structure and function (cIMT, PWV, AIx75HR) were assessed in 20 children with TSC and 17 healthy children (age ≥ 4 years). RESULTS Arterial hypertension was found in two (5.7%) patients; AML was present in 20 (57.1%) children, including 9 (27.3%) atypical AML and 22 (62.8%) had cysts in the kidneys. Children with TSC did not differ in periostin levels compared with healthy children [67.46 ± 35.61 versus 68.14 ± 24.07 (ng/mL), P = .499]. In children with TSC, periostin concentration was negatively correlated with age (r = −0.614, P < .001), height (r = −0.634, P < .001), body weight (r = −0.658, P < .001), maximum cyst size (r = −0.481, P = .004) and office and ABPM systolic and diastolic blood pressure (r = −0.396 to −0.621, P < .050). There was no relationship between periostin levels and AML size or arterial damage parameters. In multivariate analysis, the only determinant of serum periostin levels in children with TSC was age [beta = −0.547, 95% confidence interval (95% CI) (−0.831 to −0.262)]. CONCLUSION The usefulness of serum periostin determination as a marker of renal cystic lesions in children with tuberous sclerosis requires further study.