Fig. 4

Serum AMH as a marker of increased intratesticular androgen activity in patients with precocious puberty. AMH levels at diagnosis, during and after treatment in six patients with central precocious puberty. Each color line represents a different patient. Serum AMH is low for age in four of the boys with precocious puberty, indicating that there is a high intratesticular testosterone concentration that inhibits AMH expression. When testosterone production is curtailed by treatment with a GnRH analogue, serum AMH recovers prepubertal levels until treatment is withdrawn. In the remaining two cases (arrows), diagnosed before the age of 1 year, the explanation for normal prepubertal AMH levels at diagnosis, indicating a lack of AMH expression in spite of high androgen levels, is that Sertoli cells do not yet express the androgen receptor at that age. The shaded areas represent normal reference AMH levels for age. Reprinted, with modifications, from: Copyright 2013 R.P. Grinspon et al [18]