Endocrine Abstracts

Topical testosterone gels are now a widely used method of testosterone replacement therapy and have been shown to be convenient and effective. The unintentional transfer of testosterone gel to children or partners by skin contact with the application site causing hyperandrogenism has been described.

A 3-year-old well girl was referred for assessment of precocious puberty. Pubic hair had been first noted by her mother 9 months earlier. There was no history of acne, body odour or vaginal discharge. Examination revealed a tall girl (>99.9th centile; MPH 75th centile) with no breast development but Tanner stage III pubic hair and clitoromegaly. Full physical examination was otherwise normal. She was normotensive. Testosterone levels were elevated at 2.5 nmol/l, as was her Androstenedione level at 1.1 nmol/l. 17-OH progesterone was normal and tumour markers were negative. Urine steroid profile was quantitatively normal but there was a modest increase in androgen metabolites. Bone age was advanced by 16 months. Ultrasound and MRI imaging of her ovaries and adrenals did not reveal a source of androgen production. Upon further direct questioning, her father revealed he was using topical testosterone replacement therapy, applied nightly to his shoulders. The patient was a poor sleeper and often came into the parent’s bed to sleep. Her father was advised to switch application of the gel to the mornings. Her repeat testosterone level fell to <0.7 nmol/l upon retesting 4 months later and the clitoromegaly resolved. At follow up a further 6 months later, testosterone level had risen to 2.5 nmol/l. Measures to minimize secondary exposure were discussed again including showering prior to any contact with his daughter. Follow-up testing after these measures were adopted revealed normal undetectable testosterone levels (<0.7 nmol/l). Measures to minimize the risk of secondary exposure should be explained to patients using topical testosterone therapy.