RESUMO
OBJECTIVE: To investigate growth and markers of collagen and bone metabolism in prepubertal children with asthma. STUDY DESIGN: We measured growth velocity over 12 months and markers of collagen types I and III synthesis (PINP, PICP, PIIINP), collagen type I degradation (ICTP), and bone metabolism (bone-specific alkaline phosphatase and osteocalcin) on one occasion in 56 prepubertal children with stable asthma, 39 of whom were treated with inhaled budesonide or beclomethasone. Collagen data were compared with normal control values. RESULTS: Children treated with inhaled steroids had reduced collagen synthesis (PINP, PIIINP) compared with control subjects (p = 0.038, p = 0.045), although PICP was increased (p = 0.05). Carboxyterminal telopeptide of type I collagen was reduced in patients treated with inhaled steroids (p < 0.0005) compared with nonsteroid-treated patients. Serum osteocalcin but not bone-specific alkaline phosphatase was significantly reduced in children treated with inhaled steroids (p < 0.02). Significant correlation was observed between PIIINP and ICTP and growth velocity. CONCLUSION: Collagen turnover is reduced in children with asthma receiving long-term inhaled steroid treatment. Markers of collagen synthesis provide a more accurate reflection of growth disturbance than osteocalcin and bone-specific alkaline phosphatase.
Assuntos
Asma/tratamento farmacológico , Beclometasona/uso terapêutico , Osso e Ossos/metabolismo , Budesonida/uso terapêutico , Colágeno/metabolismo , Glucocorticoides/uso terapêutico , Crescimento/efeitos dos fármacos , Administração por Inalação , Fosfatase Alcalina/sangue , Fosfatase Alcalina/metabolismo , Asma/metabolismo , Asma/fisiopatologia , Beclometasona/efeitos adversos , Beclometasona/sangue , Osso e Ossos/enzimologia , Broncodilatadores/efeitos adversos , Broncodilatadores/sangue , Broncodilatadores/uso terapêutico , Budesonida/efeitos adversos , Budesonida/sangue , Criança , Pré-Escolar , Colágeno/biossíntese , Colágeno/sangue , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/sangue , Humanos , Masculino , Osteocalcina/sangue , Osteocalcina/metabolismoRESUMO
The relationship between serum concentrations of the amino-terminal propeptide of type III procollagen (PIIINP) and growth was assessed in 307 healthy subjects and 82 children with disorders of growth (41 with insufficient growth hormone, 23 with short stature and normal endocrinologic studies, 18 with tall stature) by means of a recently developed, simplified PIIINP radioimmunoassay. The PIIINP value appeared to be related to height velocity; in healthy children of each sex, the pattern of change with age mirrored the shape of the standard height velocity curve; in children with disorders of growth, there was a statistical correlation (p less than 0.001) between PIIINP concentration and height velocity. However, measurement of serum PIIINP alone had no diagnostic value because there was considerable overlap of PIIINP values in children with growth hormone insufficiency, short stature, normal stature, and tall stature. The most appropriate application of PIIINP may be in the monitoring of prepubertal children receiving exogenous growth hormone therapy; in these patients, increases in height velocity were reflected by increases in PIIINP, and early increases in PIIINP may have predictive value.