Involvement of hormonal circadian secretion in the growth of HIV-infected children

OBJECTIVE: To evalulae the circadian secretion of hormones involved in the regulation of growth in childhood, namely growth hormone, insulin-like growth factor (IGF)-I, cortisol, adrenocorticotropin hormone (ACTH), andn thyroid-stimulating hormone (TSH) in HIV-infected children. DESIGN: The circadian secretory pattern of growth hormone, IGF-I, cortisol, ACTH and TSH was evaluated in 14 HIV-infected children; 13 healthy age- and sex-matched children were chosen as controls. METHODS: Sampling was performed every 4 h from 0400 h to 2000 h and every 2 h from 2000 h to 0400 h. Rhythmometric data were analysed by single and population mean cosinor methods and by analysis of variance. RESULTS: A statistically significant circadian rhythm for growth hormone, IFG-I and cortisol was detectable in HIV-seropositive children, but the mean basel IGF-I levels were below the normal range of age in 12 patients. A statistically significant circadian rhythm was not detectable for ACTH or TSH. CONCLULSION: These results show that there is a loss of the physiological regulation of growth hormone-IGF-I axis and a modification of 24 h THS profile in our HIV-infected children. These abnormalities might be involved in the altered growth mechanisms leading to the failure to thrive that is a peculiar feature of HIV-infected children.