Aynsley-Green A, Zachmann M, Illig R, Rampini S, Prader A
Clin Endocrinol (Oxf). 1976 Jul;5(4):381-91. doi: 10.1111/j.1365-2265.1976.tb01966.x.
An evaluation of twenty-one boys, including a discordant pair of identical twins, is presented in whom bilateral anorchia was found with a negative family history and without history of breech presentation or of postnatal testicular trauma, torsion or orchitis. The most likely cause is prenatal testicular torsion. The incidence of the condition in our hospital is 1 in 177 cases of cryptorchidism. Prepubertal growth was normal before treatment, and testosterone replacement therapy allowed a normal pubertal growth spurt and skeletal maturation. Although demonstrable basal urinary testosterone was found in the subjects with a postpubertal bone age, most patients tested showed no increase after stimulation with human chorionic gonadotrophin. In the presence of a normal penis and scotum, such findings, together with a high basal FSH and an increased response of plasma LH to LHRH, make surgical exploration unnecessary. In the rare patient who shows a positive but subnormal response of testosterone to HCG, Leydig cells are presumed to be present either ectopically or in rudimentary testes, and further surgical exploration is indicated.