Q. What causes CPP/TPP ?
A. CPP occurs as an extreme variation of normal due to early HPG axis activation which may be idiopathic or it may be related to neurogenic causes with a spectrum of CNS lesions. In these instances, there is a premature decrease in the sensitivity of the gonadostat. In true precocity, the sexual maturation, growth spurt and advanced bone age are associated with pubertal levels of estrogens or androgens variable rise in the levels of gonadotropins. Increased rate of ossification results in early closure of epiphyses.

Q. Are there any specific sex differences as regards CPP ?
A. True or central precocious puberty is more common in females and the idiopathic form accounts for over 80% of cases in females but only 40% males. Organic causes involving the CNS are important in boys. Overall it is 10 fold more common in girls than boys.

Q. Which is the commonest CNS lesion causing CPP ?
A. In our country, TBM or other inflammatory lesion of CNS are important. With availability CT and MRI, underlying lesions like hypothalamic hamartomas are detected in patients who would have been diagnosed as idiopathic CPP in the past. Hamartoma is a nonprogressive hypothalamic development malformation, which constitutes an ectopic site for the production of gonadotropin releasing hormone (GnRH) that influences gonadotropin secretion. This abnormality may be associated with seizure disorders, especially gelastic epilepsy and occasionally with variable degrees of mental subnormality.

Q. Are there any other causes of precocious sexual development ?
A. One of the most intriguing complexes is the unusual syndrome of sexual precocity associated with juvenile hypothyroidism. This is the only form of sexual precocity where growth is arrested rather than stimulated. McCune Albright Syndrome may also be associated with CPP but frequently PPP due to ovarian cysts. A syndrome of gonadotropin independent precocious puberty resembling the true from has now been identified as occurring more frequently in males (familial testotoxicosis) and probably accounts for some of the familial forms of CPP reported in the past. The inheritance is sex limited autosomal dominant. Tumors like hepatoblastoma or teratoma may also produce CPP by releasing GnRH. Drugs or accidental ingestion of hormone containing pills, inadvertent use of anabolic steroids, food or vitamins contaminated with artificial estrogens, foreign body or tumors of the genital tract are some of the other causes which may cause confusion.