Practice Lesson of the Week

Sexual precocity in a 4 year old boy

BMJ 2010; 340 doi: (Published 14 May 2010) Cite this as: BMJ 2010;340:c2319
  1. A Mason, research fellow in paediatric endocrinology 1,
  2. E McNeill, endocrine nurse specialist 1,
  3. A M Wallace, consultant clinical biochemist2,
  4. J M Connell, dean of medicine and professor of endocrinology 3,
  5. M D C Donaldson, senior lecturer in child health 1
  1. 1Royal Hospital for Sick Children, Glasgow G3 8SJ
  2. 2Department of Clinical Biochemistry, Glasgow Royal Infirmary, Glasgow
  3. 3Ninewells Hospital and School of Medicine, University of Dundee
  1. Correspondence to: M D C Donaldson M.Donaldson{at}
  • Accepted 20 April 2010

Caution men treated with testosterone gel to wear clothing when in close contact with children

A boy aged 4.8 years was referred by his general practitioner with a year’s history of progressive pubic hair development and increase in length and width of the penis (figure ). Parents had also noticed a growth spurt in the previous year; the boy was now wearing age 6-7 clothes and his shoe size had increased during the past six months. There was no axillary hair, acne, or body odour.

Genitalia of 4 year old boy exposed to testosterone gel showing penile enlargement (Tanner stage G4) and pubic hair development (Tanner stage P4)

The mother was aged 43 years and in good health. The father, aged 50, had undergone pituitary surgery and radiotherapy followed by bilateral adrenalectomy for Cushing’s disease at the age of 19 and was receiving hormone replacement therapy for adrenal insufficiency and central hypogonadism.

On examination the boy measured 115.1 cm and weighed 23.8 kg. Both these measurements are above the 97th centile, according to current UK growth standards, with height well above the range expected for the parents’ heights (mother 3rd-10th centile, father 10th centile). The penis was 5.5 cm long and 6.5 cm in circumference, equivalent to Tanner stage G41 (see box); pubic hair Tanner stage 3-4; axillary hair Tanner …

View Full Text

Log in

Log in through your institution


* For online subscription