Mild Wolf-Hirschhorn phenotype and partial GH deficiency in a patient with a 4p terminal deletion.

Abstract

Wolf-Hirschhorn syndrome (WHS) is caused by a variably-sized deletion of chromosome 4 involving band 4p16 whose typical craniofacial features are "Greek warrior helmet appearance" of the nose, microcephaly, and prominent glabella. Almost all patients show mental retardation and pre- and post-natal growth delay. Patient was born at term, after a pregnancy characterized by intra-uterine growth retardation (IUGR). Delivery was uneventful. Developmental delay was evident since the first months of life. At 2 years, he developed generalized tonic-clonic seizures. Because of short stature, low growth velocity and delayed bone age, at 4 years he underwent growth hormone (GH) evaluation. Peak GH after two provocative tests revealed a partial GH deficiency. Clinical observation at 7 years disclosed a distinctive facial appearance, with microcephaly, prominent eyes, and beaked nose. Brain MRI showed left temporal mesial sclerosis. GTG banded karyotype was normal. Because of mental retardation, subtelomeric fluorescence in situ hybridization (FISH) analysis was performed, disclosing a relatively large deletion involving 4p16.2 --> pter (about 4.5 Mb), in the proband, not present in the parents. The smallest deletion detected in a WHS patient thus far includes two candidate genes, WHSC1 and WHSC2. Interestingly, that patient did not show shortness of stature, and that could be due to the haploinsufficiency of other genes localized in the flanking regions. Contribution of GH alterations and possible GH therapy should be further considered in WHS patients.