Biomedical subjects

L Tatò

Publications and source records attributed to L Tatò.

98 records · Page 6Linked to original sources

PubMedDate not supplied

[Acceleration of pubertal development].

Sexual precocity is defined as the appearance of physical signs of puberty at a time -3 SD before the mean age for the population, that is before 8 years for girls and 8.5-9.0 years for boys. The Authors discuss about etiology, therapeutic approach, indications for treatment, results and still open problems in this condition. From the pathogenetic point of view disorders that induce sexual precocity can be classified as gonadotropin-releasing hormone (Gn-RH) dependent or Gn-RH independent. Premature activation of the hypothalamic Gn-RH pulse generator may be induced by malformations, tumours and other neurogenic lesions of the CNS, while in more than 70% of patients the primary factor is not identifiable (idiopathic form). Idiopathic true precocious puberty is more frequent in females, whereas in males CNS lesions, especially neoplasms, are more prevalent. The main aims of therapy in precocious puberty are to inhibit puberty, to stop and possibly reverse the progression of secondary sex characteristics and particularly menses, to slow down skeletal maturation, to delay epiphyseas closure and consequently to improve final height, to preserve fertility, to improve psycho social well-being and naturally to treat the underlying cause, when known. Gonadotropin-releasing hormone agonists (Gn-RHa) are now the therapy of choice when the disease is Gn-RH dependent. They are effective both in arresting pubertal development and in improving final adult height. In selected cases with a great reduction of growth velocity an association with hGH therapy is possible. We must pay special attention to bone mineralization with this kind of treatment at this very delicate age.

Adolescent↗

PubMedDate not supplied

[Delayed puberty].

Delayed puberty can be defined as the absence of any signs of puberty in subjects that have attained an age at the upper limit (+2DS) for the onset of puberty, that means 13 years in girls and 14 years in boys. The causes of delayed puberty can be classified into three groups, functional temporary impairment in gonadotropin and sex steroid secretion (most frequently constitutional delay of puberty), hypothalamo-pituitary failure with deficiency in gonadotropin secretion, primary gonadal failure with increased gonadotropin levels. The Authors discuss about etiology, diagnostic testing and therapeutic approach in these conditions. The majority of children with delayed puberty are males that have only a constitutional delay of growth and puberty. It is difficult, in teenage years, to distinguish this common and benign condition from true gonadotropin deficiency, in spite of the variety of endocrine tests developed for this purpose. Individuals with constitutional delayed puberty with a bone age greater than 11.5 years, show after triptorelin stimulation an increase in LH capable of distinguishing them from patients with gonadotropin deficiency. In our opinion this could be an important screening test to exclude gonadotropin deficiency in boys with delayed puberty.

Adolescent↗

PubMedDate not supplied

[Sex differentiation and its anomalies].

Sex determination and differentiation is a sequential process that involves genetic, gonadal, phenotypic and psychological sex. Sex determination is primarily testis determination. The primary event is differentiation of the gonad; all subsequent sexual differentiation is hormonally controlled. The Authors present a classification of abnormal sexual development and consider the errors of primary sex differentiation (anomalies of sex chromosomes and of gonadogenesis) and the errors of sexual differentiation (inadequate masculinization of genetic male and virilization of genetic female). At the end the clinical approach to disorders of sexual differentiation is briefly considered.

Androgen-Insensitivity Syndrome↗

PubMedDate not supplied

[Endocrino-gynecologic problems of the female adolescent].

Adolescence is usually defined as the period of rapid physical and psychological growth and development occurring during the second decade of life. After the introduction about the physiology of puberty and menstrual cycle, the major problems in female adolescents are discussed: delayed puberty, hypo and hypergonadotropic hypogonadism, causes of primary and secondary amenorrhea, menstrual irregularity, dysfunctional uterine bleeding, dysmenorrhea, breast disorders, hirsutism, acne. Finally, adolescent pregnancy prevention and contraception are discussed. The Authors want to stress the importance of the endocrinological and gynaecological disorders in female adolescents and their impact on the psychological and emotional development at this very delicate age.

Acne Vulgaris↗

PubMedDate not supplied

[Bone mass formation in childhood and risk of osteoporosis].

The appearance of postmenopausal osteoporosis is correlated with the peak bone mass achieved during adolescence and the bone loss during adult life. The magnitude of the peak bone mass depends on genetic (race, sex, heredity), nutritional (calcium supplementation, obesity) and environmental factors as well as physical activity. Sex steroids and other hormonal factors involved in puberty, like growth hormone and insulin-like growth factors, are very important in the bone mass increase during this period. This is confirmed by studies in men with histories of constitutional delay of puberty, who have a decreased bone mineral density, and in children with precocious puberty treated with GnRH analogs, where the reduction in bone mineral density previously demonstrated seems at least completely reversible.

Bone Density↗

PubMedDate not supplied

[Empty sella syndrome: 2 cases to show its polymorphism].

Magnetic resonance imaging has proved to be the best technique to visualise the sella and juxtasellar area and it is used successfully to evaluate children with hypopituitarism or other endocraniological disorders in this area. The Authors present two cases of "empty sella syndrome", both characterized by growth hormone deficiency associated with precocious puberty in one case and with delayed puberty in the other one. The Authors stress the importance of magnetic resonance imaging in defining the morphological aspects of the hypothalamo-pituitary region and that empty sella can be associated either with pituitary hypofunction or hyperfunction.

Adolescent↗

PubMedDate not supplied

[Growth and renal function].

Some genetic conditions, as cystinosis, familial hypophosphataemic rickets, type-I vitamin D-resistant rickets and renal tubular acidosis have an impact on growth and growth failure is one of the major problem in children with chronic renal failure (CRF). In early childhood, anorexia and malnutrition, electrolyte disturbances and metabolic acidosis are the main contributing factors for reduced growth, whereas renal osteodystrophy, anemia and hormonal disturbances are responsible for growth impairment later and during puberty. During infancy, loss of growth potential can be prevented by adequate nutrition. Later in life, catch-up growth cannot be induced by nutritional intervention or dialysis and renal transplantation allows catch-up growth in only a small percentage of patients. There is evidence for a state of resistance to growth hormone (GH) and insulin-like growth factor-I (IGF-I) in CRF. GH secretion is normal, but GH half-life is prolonged and the binding activity of the GH-binding protein is reduced, which points to a low receptor expression. IGF-I production may be diminished and the serum concentration of IGF-binding proteins (IGFBP-1 and 3) is increased. The imbalance between normal IGF-I and excessive IGFBP serum levels results in decreased IGF bioactivity that plays a pathogenic role in the growth failure. This insensitivity seems to be overcome by supraphysiological doses of recombinant human GH (rhGH). Many clinical studies have confirmed that rhGH increases growth velocity in children with CRF with and without dialysis and after renal transplant, without significant side-effects. The improvement of growth is more marked in prepubertal patients and during the first year of rhGH treatment. Long-term rhGH treatment in children with CRF improves the growth potential of children, achieving target adult height. The Authors discuss the recent studies employing rhGH in renal diseases and attempt to give some guide lines to rhGH treatment in these illnesses.

Acidosis, Renal Tubular↗

PubMedDate not supplied

[Mortality from renal causes of death in an Italian population under 20 years of age in the 1979-1991 period].

The present paper addresses mortality from urinary diseases (ICD9 codes 580-599) in the Italian pediatric population aged 0-19 years, in the period 1979-91. Mortality data were obtained from the Italian National Statistical Institute (ISTAT). A total number of 522 deaths were recorded among people aged 0-19 years, amounting to 0.33% of all casualties. Half of these deaths were due to renal failure (ICD9 codes: 584-586). While mortality from all causes decreased by 35% among the Italian pediatric population, mortality from urinary diseases remained stable during the same period, and even increased in the age range 0-4 years (from 3.47 per million person-years in 1979 to 9.83 per million person-years in 1990; p < 0.001). This outbreak in mortality was entirely due to an increase in casualties from acute renal failure (ICD9 code: 584). In conclusion, since the increase in mortality from urinary diseases among Italian children aged 0-4 years takes place in the presence of a substantial drop in mortality from all causes, attention should be paid to this problem and surveillance systems should be reinforced.

Adolescent↗