Endocrine Abstracts

Testicular tumours are uncommon causes of precocious puberty (10%). The majority are Leydig cell tumours and require surgical removal plus chemotherapy. We present an 8 years (8.04 years) old male child who presented with rapid onset of pubic hair growth and right testicular swelling. Examination: his height was (143.3 cm, just above 99.6 th centile), weight (32.3 kg, 91st centile). Pubertal staging at A1, P2, G 4. Left testis 2 ml/right 8 ml. Bloods taken showed prepubertal LH (<0.2 IU/l) and FSH (0.3 IU/l), with high testosterone (7.7 nmol/l) but 17OHP (2.0 nmol/l), DHEAS (0.8 umol/l), Androstenedione (2.8 nmol/l) were normal. Tumour markers like Alfa Feto Protein (<1 kU/l) and total HCG (<1 IU/l) were also normal. Bone age (13 years) was advanced.

Pelvic ultrasound showed an enlarged right testis with a heterogeneous internal echo pattern, normal left testis and a normal CT abdomen. The right testis was removed by orchidectomy. Histology revealed Leydig cell hyperplasia with intact seminiferous tubules and no evidence of carcinomatous change. Post operative testosterone reduced to 1.6 nmol/l.

Conclusion: Onset of puberty has been caused by primary Leydig cell hyperplasia. Genetic analysis is pending but is most likely to show a gain of function mutation of the LH receptor. Continued endocrine surveillance of the contra lateral testis and assessment of adrenarche is still required. The learning point: Consider Leydig cell hyperplasia as a diagnosis in unilateral testicular swelling and do not assume a Leydig cell tumour is the cause.