Progressive Decline in Height Standard Deviation Scores in the First 5 Years of Life Distinguished Idiopathic Growth Hormone Deficiency from Familial Short Stature and Constitutional Delay of Growth.

BACKGROUND: Familial short stature (FSS) and constitutional delay of growth (CDG) are the most frequent norm variants in children presenting with short stature. Knowing the growth patterns of these entities in the first years of life might be helpful to distinguish them from growth hormone deficiency (GHD) or other chronic diseases.

METHODS: We studied the height in the first 5 years of life in 26 children with FSS, in 38 children with CDG and in 14 children with idiopathic GHD.

RESULTS: Height standard deviation scores (SDS) did not change between birth and 6 months of life, while height SDS decreased significantly afterwards in GHD, FSS, and CDG. The loss of height SDS was higher in the first 2 years of life than between 2 and 5 years of life in children with CDG (-0.92 vs. -0.11; p = 0.003) or FSS (-0.79 vs. -0.01; p = 0.002). In idiopathic GHD, the loss of height SDS did not differ between the first 2 years of life and the next 3 years (-0.78 vs. -0.77; p = 0.821).

CONCLUSION: Children with FSS and CDG showed a decline in height SDS mainly in the first 2 years of life, whereas the height SDS of children with idiopathic GHD decreased almost continuously over the first 5 years of life.