Premature Pubarche due to Exogenous Testosterone Gel or Intense Diaper Rash Prevention Cream Use: A Case Series.

BACKGROUND/AIMS: Premature pubarche is associated with conditions such as virilizing congenital adrenal hyperplasia, androgen-secreting tumors, and exogenous exposure to androgen products. We describe the clinical and hormonal features of a series of children who were referred to endocrine evaluation due to premature pubarche. METHODS: This is a retrospective case series study of 14 children with premature pubarche and/or virilization. Five were unintentionally exposed to testosterone gel (parental use). Nine patients were intensely exposed to diaper rash prevention creams. Clinical and laboratory data were revised. RESULTS: Moderate to severe virilization was detected in the 5 patients (2 boys and 3 girls) who were exposed to testosterone gel. These patients had pubic hair development associated with clitoromegaly (3/3), penile enlargement (2/2), and accelerated growth (5/5). Testosterone levels were elevated in 4/5 patients associated with normal prepubertal gonadotropin levels and adrenal androgen precursors. The 9 children who were intensely exposed to diaper rash prevention creams had mild pubarche (intermediate hair) without any other clinical manifestation of pubertal development. Three of them exhibited pubic hair thinning after cream withdrawal. CONCLUSION: Unintentional topical androgen exposure or the intense use of diaper rash prevention cream should be ruled out in children with precocious pubarche and/or virilization signs to avoid misdiagnosis and expendable investigation.

Sexual Precocity--Genetic Bases of Central Precocious Puberty and Autonomous Gonadal Activation.

Precocious puberty has been classically defined as the onset of sexual secondary characteristics in girls younger than 8 years and in boys younger than 9 years. The discovery of potential factors which trigger human puberty is one of the central mysteries of reproductive biology. Several approaches, including mutational analysis of candidate genes, large-scale genome-wide association studies, and (more recently) whole-exome sequencing, have been performed in attempt to identify novel genetic factors that modulate the human hypothalamic-pituitary-gonadal axis, resulting in premature sexual development. In the last two decades, it has been well established that autonomous gonadal activation can be caused by somatic (GNAS) or germline (LHCGR)-activating mutations of genes that encode essential elements for signal transduction of G protein-coupled receptors, resulting in peripheral precocious puberty in McCune-Albright syndrome and testotoxicosis, respectively. More recently, dominant activating and inactivating mutations of excitatory (KISS1/KISS1R) and inhibitory (MKRN3) modulators of gonadotropin-releasing hormone secretion, respectively, were associated with central precocious puberty phenotype. Indeed, loss-of-function mutations of MKRN3, a maternal imprinted gene located at chromosome 15q, currently represent a frequent cause of central precocious puberty diagnosed in families from distinct geographic origins. Here, we review the known genetic defects in central and peripheral precocious puberty.