[Ambulatory diagnostic methods in disorders of sex maturation]

The most important investigative methods for study of disorders of pubertal development are simple. However, they require a detailed knowledge of the normal course of puberty. In most cases the family history (height of the parents, course of puberty in the father, age at menarche of the mother), personal history (growth curve, height velocity) and physical examination (height measurement, evaluation of stage of pubertal development, bone age) make it possible to decied whether there is benign delayed growth and development (a variation of normal) or whether the patient is suffering from one of the rare types of true hypogonadism (hormonal disorder or types of true hypogonadism (hormonal disorder or chromosomal anomaly). Only when there is strong suspicion of hypogonadism should the expensive and complicated laboratory and chromosome studies be carried out. They serve to detect a disorder of the end organ or of the hypothalamus-pituitary system (determination of testosterone or estradiol, determination of LH and FSH before and after stimulation with the releasing hormone LHRH, determination of growth hormone before and after insulin and arginine, determination of TSH before and after TRH). Although endocrine disorders are rarely the cause of delayed puberty, their diagnosis is important with a view to causal treatment.