Biomedical subjects

S Zucchini

Publications and source records attributed to S Zucchini.

5 recordsLinked to original sources

PubMed1992

Magnetic resonance imaging of the pituitary area in children treated for acute lymphoblastic leukemia with low-dose (18-Gy) cranial irradiation. Relationships to growth and growth hormone secretion.

OBJECTIVE: To determine the effects of 18-Gy cranial irradiation on growth, growth hormone (GH) secretion, and pituitary magnetic resonance imaging in children who underwent previous irradiation for treatment of acute lymphoblastic leukemia. DESIGN: Clinical survey. SETTING: Department of Pediatrics of the University of Bologna (Italy). PATIENTS: Ten boys and 18 girls who were treated for acute lymphoblastic leukemia; median age at diagnosis was 3.1 years and at the end of follow-up was 11.5 years. MEASUREMENTS AND RESULTS: Height was periodically measured from diagnosis until the end of follow-up, when GH secretion study and magnetic resonance imaging were performed. The mean height SD score was significantly lower than at diagnosis only at the end of treatment. Nocturnal mean GH concentration and GH response to pharmacological tests (arginine and levodopa [L-dopa]) were pathological in 22 cases (81.5%) and 18 cases (64.3%), respectively. Sixteen cases (59.2%) had a blunted GH release to the three tests. Mean pituitary anterior lobe height was reduced and seven subjects (25%) showed an empty sella. CONCLUSIONS: Cranial irradiation with 18 Gy does not seem to influence the growth pattern of most children who are treated for acute lymphoblastic leukemia, despite severe impairment of GH secretion and morphological abnormalities of the sellar area. However, a follow-up until final height is necessary.

Adolescent↗

PubMed1992

Pitfalls in diagnosing impaired growth hormone (GH) secretion: retesting after replacement therapy of 63 patients defined as GH deficient.

Possible causes of error in the diagnosis of isolated GH deficiency are the variability of GH response to repeated tests, the existence of transient GH deficiencies, and the low GH levels found in short statured children with delayed puberty. Sixty-three patients with variously expressed GH deficiency were retested (1 sleep test and 2 pharmacological tests) after 1-3.9 yr of GH therapy (dose, 15 U/m2.week). Forty-eight subjects had arginine, L-dopa, and sleep tests (mean serum GH concentration) twice, while 15 had only arginine and L-dopa tests. All patients were retested 1 month after withdrawal from therapy. The criteria used to subdivide the patients were pubertal development and response to pharmacological and sleep tests at first diagnosis and on retesting. The initial diagnosis in 33 subjects (52.4%) was not confirmed, and 13 (20.6%) were no longer deficient on retesting. The percentage of normalization was high for the sleep test (43.9%), lower for the pharmacological test (24.5%), and lower still (12.9%) for pharmacological and sleep tests considered together. While none of the 28 subjects who remained prepubertal at retesting normalized in any of the tests, 13 of the 35 subjects retested during puberty did. When normalization was observed in pubertal subjects, it occurred predominantly in the sleep test. Growth velocity and height age/bone age increment ratio after the first year of therapy were no different for the groups of subjects classified according to GH secretion on retesting. Our study demonstrates that a number of children diagnosed as GH deficient do not have a true deficiency. However, such a diagnostic error seems to have little effect, at least in the first year of therapy, on the effectiveness of GH treatment.

Adolescent↗

PubMed1990

Endocrine function and morphological findings in patients with disorders of the hypothalamo-pituitary area: a study with magnetic resonance.

Evaluation of the sellar area was performed with magnetic resonance imaging in 101 patients (age range 0.8-27 years) with hypopituitarism, isolated diabetes insipidus, hypogonadotrophic hypogonadism, and central precocious puberty. The hypopituitary patients (n = 70) included multiple pituitary deficiency (n = 23), pituitary deficiency with diabetes insipidus (n = 5), and isolated growth hormone deficiency (n = 42). The patients with multiple pituitary deficiency showed pathological morphological findings in all cases, with stalk and posterior lobe always involved. The group with associated diabetes insipidus had abnormal stalk in four of five cases and posterior lobe not visible in all cases. Only five of 42 (12%) patients with isolated growth hormone deficiency had abnormalities of the sellar area. In two out of four patients with isolated diabetes insipidus posterior lobe was not seen. All patients with hypogonadotrophic hypogonadism (three with Kallmann's syndrome, one Prader-Willi syndrome, and two idiopathic hypogonadism) appeared normal. In precocious puberty (n = 21) the three patients with onset of symptoms before age 2 years exhibited a hypothalamic hamartoma, whereas in the others with onset of puberty between age 2 and 7 the magnetic resonance image was normal in 17 of 18 patients. The probability of finding a pathological magnetic resonance image was considerably high in our patients with multiple pituitary deficiency, isolated diabetes insipidus, and precocious puberty with very early onset of symptoms. On the contrary, purely functional abnormality is suggested in most patients with isolated growth hormone deficiency, hypogonadotrophic hypogonadism, and precocious puberty with later onset of symptoms.

Adolescent↗

PubMed1990

Variability of growth hormone response to pharmacological and sleep tests performed twice in short children.

Forty-nine children with short stature (age range, 4.1-15.9 yr) were examined. Twenty-four (group 1) were submitted twice to an arginine and a sleep test (12-h overnight GH profile). Twenty-five patients (group 2) were submitted twice to an arginine and L-dopa test. Coefficients of variation were calculated between both the results of pharmacological (peak and area under the curve) and sleep tests [mean GH concentration (MGHC), peak, area under the curve, number of peaks above 5 micrograms/L, and peak area]. In group 1 the coefficient of variation of sleep test parameters was significantly lower than that of pharmacological tests (P less than 0.01 to less than 0.001). In the sleep test the area under the curve and MGHC were the most constant parameters. Group 2 showed no difference between the coefficients of variation of the two pharmacological tests. Considering groups 1 and 2 together, the coefficients of variation of the sleep test, in particular the MGHC and area under the curve, were lower than those of the two pharmacological tests. Eight of 24 subjects in group 1 showed a low GH level in 1 series of tests, and a normal level in the other series. Five of 18 subjects in group 2 showed an abnormally low GH response to the arginine and L-dopa tests and a normal response to the 2 repeated tests. Therefore, to prevent an erroneous interpretation of the GH test results, it is very important to perform a sleep test and repeat it whenever GH secretion seems to be deficient or at the lower limits of normalcy.

Adolescent↗

PubMedDate not supplied

[Cryptorchidism].

Cryptorchidism is a frequent abnormality which affects approximately 1% of children at age 1 year. Many nonscrotal testes are retractile and require no therapy. The pathogenesis remains controversial and involves possible mechanical, dysgenetic or hormonal factors. The latter are consistent with a partial defect in the hypothalamo-pituitary-gonadal axis, which may cause progressive histologic alterations in the testes after the first 6 months of life. Ultrasound is the simplest diagnostic technique (after clinical examination) to identify the testes in the inguinal region, while Magnetic Resonance Imaging can be performed to visualize abdominal testes. Therapy is still a matter of controversy. Hormonal treatments with HCG, LHRH or both should be used as first-intention treatment and their efficacy ranges from 0% to 60% in the various studies. LHRH nasal spray seems less effective if used alone. An early surgical treatment is recommended if the gonad is in the abdomen or close to the internal inguinal ring. The risk of cancer is increased in subjects with a history of cryptorchidism and even includes the contralateral descended testes. Early orchidopexy is not associated with a certain decrease of the risk. Cancer can be prevented by searching for in situ carcinoma with a biopsy performed after puberty. Fertility is impaired mainly in men with a history of bilateral cryptorchidism. There is weak evidence that early orchidopexy may improve fertility rates.

Adolescent↗