ABSTRACT
AIM: The aim of this study was to evaluate the positive predictive value of two growth hormone stimulation tests (insulin-induced hypoglycemia and clonidine) for stature below percentile 10 in patients treated for acute lymphoblastic leukemia in childhood. METHODS: The study population was a cohort of 30 patients (aged 14.1+/-2.9 years; 20 male) treated for acute lymphoblastic leukemia during childhood and then examined after insulin-induced hypoglycemia (30 patients) and clonidine (16 patients) tests. The follow-up time was 7.7+/-2.8 years since treatment and 2.3+/-1.3 years after administration of the tests. RESULTS: In the last evaluation, 12 patients (40%) were below and 18 (60%) were above percentile 10. The insulin-induced hypoglycemia test response was: 9 patients (30%) had growth hormone peak <5 ng/mL and 19 (63.3%) <7 ng/mL. The clonidine test response was: 7 patients had growth hormone peak <5 ng/mL and 8 (50%) <7 ng/mL. For stature below of the percentile 10, the positive predictive values of insulin-induced hypoglycemia test (33%) and clonidine (28%) were low when growth hormone peak <5 ng/mL was considered; however, when growth hormone peak <7 ng/mL was considered, the positive predictive values were 83% and 50% for the insulin-induced hypoglycemia and clonidine tests, respectively. CONCLUSIONS: In patients treated for acute lymphoblastic leukemia in childhood, the positive predictive values for statural deficit of both tests were low, except for the insulin-induced hypoglycemia test when a growth hormone peak <7 ng/mL was considered.
Subject(s)
Body Height/drug effects , Body Height/radiation effects , Human Growth Hormone/deficiency , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Adolescent , Adrenergic alpha-Agonists , Child , Child, Preschool , Clonidine , Cohort Studies , Drug Therapy, Combination , Female , Human Growth Hormone/blood , Humans , Hypoglycemic Agents , Insulin , Male , Predictive Value of TestsABSTRACT
In view of the correlation of the circadian system with the estrous cycle in the rat, some investigators have proposed the induction of polycystic ovaries by exposing rats to continuous light. However, there is divergence with respect to time of exposure and light intensity. in the present paper we propose a simple and efficient experimental model for the study of polycystic ovarian physiopathology in rats. Twenty female Wistar rats weighing 200-220 g were initially submitted to a 14-h light/10-h dark cycle. of the animals with regular estrous cycles, 9 were exposed to continuous light (600 lux) for 74 days (group 1) and 6 remained under the initial lighting conditions. A daily vaginal smear was used as indirect evidence for the changes in the estrous cycle. Plasma gonadotropin measurement and histological ovarian analysis showed that 90% of the animals in group 1 developed cystic follicles with the absence of the corpus luteum, despite the lack of reduction in ovarian weight commonly observed under 24-h lghting. This observation may be explained by the reduced time of stress to which the animals were submitted, since polycystic ovarian development occurred within less than 75 days of continuous exposure to 600-lux light, a time relatively shorter than commonly reported in the literature
