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

Presentation and Care for Children with Peripheral Precocious Puberty

Peripheral precocious puberty (PPP) refers to the early onset of sexual maturation that is independent of central nervous system control. The extensive differential diagnosis includes congenital and acquired causes. Presenting features depend on which class of sex steroids is involved, and diagnosis rests on hormonal and, if indicated, imaging and/or genetic studies. Effective treatment exists for nearly all causes of PPP. Ongoing research will advance our therapeutic armamentarium and understanding of the pathophysiologic basis of these conditions.

Update on Adrenarche-Still a Mystery

CONTEXT

Adrenarche marks the timepoint of human adrenal development when the cortex starts secreting androgens in increasing amounts, in healthy children at age 8-9 years, with premature adrenarche (PA) earlier. Because the molecular regulation and significance of adrenarche are unknown, this prepubertal event is characterized descriptively, and PA is a diagnosis by exclusion with unclear long-term consequences.

EVIDENCE ACQUISITION

We searched the literature of the past 5 years, including original articles, reviews, and meta-analyses from PubMed, ScienceDirect, Web of Science, Embase, and Scopus, using search terms adrenarche, pubarche, DHEAS, steroidogenesis, adrenal, and zona reticularis.

EVIDENCE SYNTHESIS

Numerous studies addressed different topics of adrenarche and PA. Although basic studies on human adrenal development, zonation, and zona reticularis function enhanced our knowledge, the exact mechanism leading to adrenarche remains unsolved. Many regulators seem involved. A promising marker of adrenarche (11-ketotestosterone) was found in the 11-oxy androgen pathway. By current definition, the prevalence of PA can be as high as 9% to 23% in girls and 2% to 10% in boys, but only a subset of these children might face related adverse health outcomes.

CONCLUSION

New criteria for defining adrenarche and PA are needed to identify children at risk for later disease and to spare children with a normal variation. Further research is therefore required to understand adrenarche. Prospective, long-term studies should characterize prenatal or early postnatal developmental pathways that modulate trajectories of birth size, early postnatal growth, childhood overweight/obesity, adrenarche and puberty onset, and lead to abnormal sexual maturation, fertility, and other adverse outcomes.

Normal and Premature Adrenarche

Adrenarche is the maturational increase in adrenal androgen production that normally begins in early childhood. It results from changes in the secretory response to adrenocorticotropin (ACTH) that are best indexed by dehydroepiandrosterone sulfate (DHEAS) rise. These changes are related to the development of the zona reticularis (ZR) and its unique gene/enzyme expression pattern of low 3ß-hydroxysteroid dehydrogenase type 2 with high cytochrome b5A, sulfotransferase 2A1, and 17ß-hydroxysteroid dehydrogenase type 5. Recently 11-ketotestosterone was identified as an important bioactive adrenarchal androgen. Birth weight, body growth, obesity, and prolactin are related to ZR development. Adrenarchal androgens normally contribute to the onset of sexual pubic hair (pubarche) and sebaceous and apocrine gland development. Premature adrenarche causes ≥90% of premature pubarche (PP). Its cause is unknown. Affected children have a significantly increased growth rate with proportionate bone age advancement that typically does not compromise growth potential. Serum DHEAS and testosterone levels increase to levels normal for early female puberty. It is associated with mildly increased risks for obesity, insulin resistance, and possibly mood disorder and polycystic ovary syndrome. Between 5% and 10% of PP is due to virilizing disorders, which are usually characterized by more rapid advancement of pubarche and compromise of adult height potential than premature adrenarche. Most cases are due to nonclassic congenital adrenal hyperplasia. Algorithms are presented for the differential diagnosis of PP. This review highlights recent advances in molecular genetic and developmental biologic understanding of ZR development and insights into adrenarche emanating from mass spectrometric steroid assays.

Diagnosis and management of precocious sexual maturation: an updated review

The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. It is classified as central precocious puberty when premature maturation of the hypothalamic-pituitary-gonadal axis occurs, and as peripheral precocious puberty when there is excessive secretion of sex hormones, independent of gonadotropin secretion. Precocious sexual maturation is more common in girls, generally central precocious puberty of idiopathic origin. In boys, it tends to be linked to central nervous system abnormalities. Clinical evaluation should include a detailed history and physical examination, including anthropometric measurements, calculation of growth velocity, and evaluation of secondary sexual characteristics. The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. Hormonal assessment and imaging are required for diagnosis and identification of the etiology. Genetic testing should be considered if there is a family history of precocious puberty or other clinical features suggestive of a genetic syndrome. Long-acting gonadotropin-releasing hormone analogs are the standard of care for central precocious puberty management, while peripheral precocious puberty management depends on the etiology.Conclusion: The aim of this review is to address the epidemiology, etiology, clinical assessment, and management of precocious sexual maturation. What is Known: • The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. • Long-acting gonadotropin-releasing hormone agonist (GnRHa) is the standard of care for CPP management, and adequate hormone suppression results in the stabilization of pubertal progression, a decline in growth velocity, and a decrease in bone age advancement. What is New: • Most cases of precocious sexual maturation are gonadotropin-dependent and currently assumed to be idiopathic, but mutations in genes involved in pubertal development have been identified, such as MKRN3 and DLK1. • A different preparation of long-acting GnRHa is now available: 6-month subcutaneous injection.

Precocious sexual development in a male toddler caused by unrecognized transdermal exposure to testosterone: case report and review of the literature

OBJECTIVES

Exogenous exposure to transdermal testosterone is often overlooked as a cause of precocious sexual development in children.

CASE PRESENTATION

A 16-month-old male presented for a second opinion consultation before commencing treatment with bicalutamide and anastrozole for a presumptive diagnosis of familial gonadotropin-independent male-limited sexual precocity. Enlargement of the penis was first observed at four months of age. The initial evaluation showed isolated elevation of his plasma testosterone level; however, by 16 months, his testosterone level was prepubertal and no pathogenic variants in the LHC GR gene were identified. The history revealed that his grandfather, who had cared for him regularly in the first year of life, had used testosterone gel for treatment of hypogonadism.

CONCLUSIONS

Despite the 2009 "black box" warning issued by the United States Food and Drug Administration (FDA) regarding potential consequences of transdermal testosterone exposure to women and children, this continues to be an important cause of sexual precocity in children. Children are often subjected to unnecessary and costly evaluation before this exposure is recognized, underscoring the importance of obtaining a thorough medical, family, and social history tailored to the differential diagnosis.