Adolescent boys with constitutional delay of growth and puberty grow faster than patients with organic growth hormone deficiency.

OBJECTIVE: Constitutional delay of growth and puberty (CDGP) is a tempo variant with a good prognosis. Healthy late-maturing adolescents grow slower than postulated by age-related references, and therefore, CDGP is frequently confused with growth hormone deficiency (GHD). For differential diagnosis, height velocity references for CDGP are needed. DESIGN AND PATIENTS: Here, we provide height velocity data for late-maturing boys based on mixed longitudinal and cross-sectional observations in a group of 38 German adolescents with proven CDGP and compare them with cross-sectional observations in a group of 164 adolescents with organic GHD from the National Cooperative Growth Study registry. RESULTS: In the critical age interval from 13.4 to 14.9 years, the growth of prepubertal adolescents with CDGP was faster (mean/median height velocity, 5.2/5.4 cm/years; quartiles, 4.4-6.2 cm/years) than that of prepubertal adolescents with organic GHD (3.5/3.2 cm/years; quartiles, 2.0-4.4 cm/years) in the cross-sectional analysis (p < .0001). Based on our mixed longitudinal and cross-sectional analysis, the height velocity of adolescent boys with CDGP exceeded previous model calculations on average by 1.0 cm. CONCLUSIONS: In conclusion, prepubertal adolescents with CDGP grow faster than patients with organic GHD. Previous model estimates underestimated height velocity of boys with CDGP.