ESPE Yearbook of Paediatric Endocrinology

Brief Summary: this retrospective study describes clinical and biochemical parameters which, using the principal component analysis, help in the differential diagnosis between idiopathic central precocious puberty (ICPP) and premature thelarche (PT).

Breast development in girls before 8 years of age may be related to progressive CPP but can sometimes simply be the consequence of premature thelarche without activation of the hypothalamic-pituitary-gonadal axis.

This study showed that clinical, anthropometric, radiological, and biochemical markers in combination can distinguish between these two entities without need for GnRH stimulation testing

Between 2009 to 2019, 1316 girls were referred to a single tertiary centre of pediatric endocrinology in Denmark and included in the study. After applying exclusion criteria, 474 patients remained and were divided according to diagnosis (idiopathic central precocious puberty, organic central precocious puberty, premature thelarche, premature adrenarche, peripheral precocious puberty). ICPP in girls was defined as Tanner stage ≥ B2 before 8 years of age, and either a basal concentration of LH >0.3 IU/L and/or a pubertal response to a GnRH stimulation test (peak LH > 5 IU/L)¹.

Receiver operating analyses allowed the identification of markers to differentiate between girls with ICPP and PT (advancement in bone age, serum concentrations of basal FSH, basal LH, testosterone, androstenedione, and IGF-I). The use of principal component analysis increased their diagnostic value, which remains low when using them individually. Principal component analysis-derived clinical and hormone profiles could predict girls with ICPP from girls with PT with a specificity of 90% and sensitivity of 84%, outperforming any single marker. This offers clinicians an alternative approach in the early outpatient setting and before resorting to a stimulation test.

Reference: 1. Neely EK, Wilson DM, Lee PA, Stene M, Hintz RL. Spontaneous serum gonadotropin concentrations in the evaluation of precocious puberty. J Pediatr. 1995;127(1):47-52.