A child with manifestations of acrogeria and
metageria, two "
premature aging" syndromes, is presented. Because of his indistinct phenotype and because the question has been previously raised as to whether these conditions are separate, we propose the designation of
acrometageria to describe this phenotypic continuum. As there is much in common clinically between
acrometageria and the syndrome of
type III procollagen deficiency (Ehlers-Danlos type IV), it might be presumed that a similar pathogenesis for
acrometageria exists. This possibility has been tested previously, without demonstrating specific quantitative or qualitative deficits, but with some indirect evidence that
collagen metabolism is deranged in these patients. One such crude
indicator is the elevation of urinary
hyaluronic acid levels, demonstrated in our patient and also observed in the phenotypically distinct Werner and Hutchinson-Gilford
premature aging syndromes. On one hand, it could be argued that this supports the concept that
premature aging syndromes exist as a
biological continuum. On the other hand, it is equally valid to argue that syndromes of
premature aging are so described merely because they include recognizable changes of normal aging and that the demonstration of an underlying mutation in a
collagen gene, for example, invalidates their study as models of accelerated normal aging.