Hypopituitary Dwarfism

Abstract

The pediatric definition of the term dwarfism is applied to children whose height is 4 standard deviations or more (≥4 SD) below the mean of their coevals. Primary disturbances in growth regulation can be caused by a myriad of disease states. Intrinsic abnormalities of bone or cartilage as well as numerous systemic diseases affect growth (Table 26). The focus in this chapter

Table 26 Causes of Short Stature

is on growth retardation caused by hyposomatotropism. Several terms used in the past, including primordial dwarfism, ateleotic dwarfism, genetic dwarfism, and constitutional dwarfism, have been mostly discarded currently, owing to the meaningless nature of such terms. It used to be believed that growth hormone (GH) deficiency represented a relatively uncommon (5–10%) cause of growth retardation. This belief was fostered in an era when GH deficiency was a relatively simple and straightforward entity (i.e., failure to grow was clearly a result of failure to generate GH by the anterior pituitary). In the short span of merely the past 10 years, GH-related growth disorders have come to be recognized as a heterogeneous group of disorders with diverse underlying mechanisms. Indeed, this entity is rapidly being elevated to the status of a fairly common etiology for growth retardation. Regardless of the frequency of occurrence, GH-related growth disorder may be the only group— besides hypothyroidism—in which some therapeutic rewards are attainable; a fact that is especially important, since delays in diagnosis can cost tremendous psychosocial maladjustments.