NONSYNDROMAL OVERGROWTH IN MALES WITH MILD PSYCHOMOTOR DELAY

Over the last 3 years we ascertained 42 patients for statural overgrow th and/or macrocephaly, who also had mild developmental delay. There w ere 39 males and three females, two of whom were sisters. In no case w as tall stature a familial characteristic, Family history was unremark able, except for the case of the two sisters. Physical examination did not demonstrate any consistent pattern of malformations or anomalies identifying a syndrome, known or unknown, Chromosomes were apparently normal and the molecular test for the fragile X syndrome yielded norma l results in all cases, Muscular hypotonia, advanced bone age, and epi lepsy were relatively consistent manifestations, The hypothalamus-pitu itary axis seemed to be intact when tested through the blood levels of insulin-like growth factors I and II and of the insulinlike growth bi nding protein 3, and the excess of growth was apparently growth hormon e independent. The condition comprising excessive growth, developmenta l delay, muscular hypotonia, absence of a consistent pattern of physic al anomalies, and apparently sporadic occurrence, largely limited to m ales, may be heterogenous. (C) 1998 Wiley-Liss, Inc.