Final height in congenital adrenal hyperplasia due to 21-hydroxylase deficiency: the Italian experience.

Objective: To investigate the influence of target height (TH), gender, phenotype, glucocorticoid formulation and age at onset of treatment on final height (FH) in patients with 21-hydroxylase deficiency (21OHD).
Patients: Clinical data of 93 patients--46 simple virilizing (SV), 35 salt-wasting (SW) and 12 late onset (LO)--were collected in six pediatric endocrinology units in Italy.
Results: FH and TH were always below the mean height of the general population (mean FH, SDS: SW patients -1.3 +/- 1.2, SV patients -1.8 +/- 0.9, LO patients -1.7 +/- 1.1; mean TH, SDS: SW patients -0.6 +/- 0.8, SV patients -0.7 +/- 0.9, LO patients -1.4 +/- 1.3). FH was significantly below TH in patients with classic form (SW and SV, p <0.001), but not in LO patients. In classic form, TH seems to be related to FH, followed by age at onset of therapy and by steroid formulation, these variables explaining 30% of FH variance.
Conclusions: In the classic form, substitutive therapy started before 21 months of age improved the long-term outcome. Lower TH in LO patients could be due to undiagnosed non-classic 21OHD in some of their parents. FH in LO patients seems not to benefit from corticosteroid therapy, even if late diagnosis may partly account for this result.