Endocrine Abstracts

Background: Pseudo precocious puberty in young children usually arises from adrenal or less commonly testicular causes. Though rare, the possibility of an exogenous source should also be considered.

Case Report: A 2 year 2 month old male child presented with apparent overgrowth since about 1 year of age. His height was 108 cms [+6.29 SDs], weight 21 kgs [+4.54 SDs] and head circumference 52.2 cms [2.76 SDs]. He looked very mature for his age but had no dysmorphic features. He had significant penile development and stage 2 pubic hair but small testes. He also had morning erections and challenging behaviour but was developmentally age appropriate. Investigations confirmed a raised testosterone 3.4 nmol/l and IGF1 35.1 nmol/l but normal thyroid function and random cortisol. A urinary steroid profile excluded congenital adrenal hyperplasia and adrenal tumours and an abdominal ultrasound was normal. Shortly afterwards, the testosterone was repeated and was now 14.1 nmol/l; a GnRH test was unsuccessful but the basal gonadotrophins were undetectable. The plasma adrenal androgens were also low. His bone age was very advanced at 4.6 years. On further enquiry, it emerged that his father, who was an active carer, has been using daily topical testosterone gel for hypogonadism for over 2 years. His metered dose totalled 60.75 mg daily and was applied every morning to his bare hands and then transferred to his shoulder areas. He said he washed his hands after application. He was asked to stop using the gel and consider alternative replacement treatment: a repeat testosterone level in the child one month later was undetectable.

Discussion: Transfer of topical testosterone gel between adults, often between sexual partners, is well known but is rarely recognised in children. Apart for the exclusion of other causes of a raised testosterone in a young child, the extreme variation in the measured testosterone level was highly suggestive of an exogenous source. Routine enquiry about family use of testosterone gels should considered in pseudo precocious puberty in young children.