Etiology of central precocious puberty in males: the results of the Italian Study Group for Physiopathology of Puberty.

We reviewed the hospital records of 45 boys, followed in 13 pediatric departments throughout Italy, who had undergone computed tomography and/or magnetic resonance imaging for central precocious puberty (CPP). Twenty-seven patients (60%) had idiopathic CPP and 18 (40%) neurogenic CPP. A hamartoma of the tuber cinereum was found in six patients (33%). All patients with hypothalamic hamartoma had earlier onset of symptoms than patients with idiopathic CPP. Five patients (27%) were affected by type 1 neurofibromatosis, two had ependymoma and five patients had an intracranial anomaly. Basal LH and basal and peak LH/FSH ratio were greater, but not significantly, in boys with neurogenic CPP than in boys with idiopathic CPP. The highest LH peak levels were observed in patients with hamartoma; however, no correlation was observed between LH peak and the size of the hamartomas. In addition, bone age at diagnosis was more advanced in patients with hamartoma than in patients with other conditions. In conclusion, gonadotrophin-dependent precocious puberty may be of idiopathic origin or may occur in association with any CNS disorder. Further studies are needed in order to evaluate the effects of nutritional, environmental and psychosocial factors on the timing of sexual maturation, to explain the high incidence of idiopathic CPP in our male patients.