ESPE Abstracts

Introduction: Klotho is a protein which may serve as a regulator of GH secretion. Growth hormone deficiency is diagnosed in children with growth restriction when GH secretion in two GH stimulation tests do not exceed the level of 10 ng/ml.

Aim: The objective of the study was to investigate Klotho and FGF23 in children with growth hormone deficiency (GHD) and their responce to the treatment with recombinant human growth hormone (rHGH).

Patients and methods: The study group consisted of 78 patients (boys 45, girls 33) with GHD diagnosed in one pediatric tertiary center. Their median age was 7.43 years [4.88;10.48]. The control group consisted of 28 children of a similar age and sex. Prior to and following a period of 6 months of treatment with rHGH anthropometrical data were recorded, and biochemical parameters were measured: Klotho, FGF23, IGF-1, IGFBP-3, 25-OH vitamin D, PTH, calcium, phosphate, alkaline phosphatase. Blood was sampled in the morning in fasting conditions. SDS for height, BMI, IGF-1S, and IGFBP-3 was calculated.

Results: Klotho levels in the group of children with GHD before treatment with rHGH (1664.4 pg/ml [1233.14;2125.87]) was lower than in the control group (2081.82 pg/ml [1372.13;2730.81]). The difference was statistically significant (P=0.046). The treatment with rHGH caused acceleration of height velocity from 5.05+/−1,54 to 9.35+/−2.02 cm/yeat (P=0.000) and IGFSDS from −1.64 [−1.99;−1.31] to −0.75 [−1.31;−0.17]. After 6 months of treatment with rHGH in children with GHD Klotho levels increased to 2939.85 [1867.03;3853.04], P=0.000. We did not observed similar trend for FGF23. In children with GHD on rHGH treatment Klotho correlated positively with PTH (P=0.001), and IGF1 (P=0.007).

Conclusion: Klotho protein can be used as a sensitive marker of GHD. It also can be used as a marker of the response to the treatment with rHGH.