Serum kisspeptin, neurokinin Band inhibin B levels can be used as alternative parameters to distinguish idiopathic CPP from premature thelarche in the early stages of puberty.

Abstract

There is controversial results about serum kisspeptin, neurokinin-B (NKB), anti-Müllerian hormone (AMH)and inhibin B (INHB) levels in girls with central precocious puberty (CPP). Aim of this study is to evaluate serum levels of these four peptides in patients presented with early pubertal signs, and to evaluate their diagnostic validity in the diagnosis of CPP. Cross-sectional study. Study included 99 girls (51 CPP, 48 premature thelarche [PT]) whose breast development started before 8 years and 42 age-matched healthy prepubertal girls. Clinical findings, antropometric measurements, laboratory and radiological findings were recorded. Gonadotropin-releasing hormone (GnRH) stimulation test was performed in all cases with early breast development. Kisspeptin, NKB, INHBand AMH levels were measured in fasting serum samples using enzyme-linked immunosorbent assay method. There was no statistically significant difference between mean ages of girls with CPP (7.1 ± 1.2 years), PT (7.2 ± 1.3 years)and prepubertal controls (7.0 ± 1.0 years). Serum kisspeptin, NKBand INHB levels were higher in CPP group compared to PT and control groups, while serum AMH level was lower in CPP group. Serum kisspeptin, NKB, and INHB were all positively correlated with bone age (BA) advancement, and peak luteinizing hormonein GnRH test. Multiple stepwise regression analysis revealed that the most important factors used to differentiate CPP from PT were advanced BA, serum kisspeptin, NKB and INHB levels (AUC: 0.819, p < .001). We, firstshowed in the same patients' group that serum kisspeptin, NKB and INHB were higher in patients with CPP and can be used as alternative parameters to distinguish CPP from PT.