A case of apparent hypopituitarism complicating chronic inflammatory bowel disease in childhood and adolescence.

There is conflicting evidence regarding the adequacy of hypothalamic-pituitary function in children and adolescents with chronic inflammatory bowel disease complicated by growth retardation and delayed sexual maturation. A child with Crohn's disease, who has never received corticosteroid therapy, had delay of both growth and sexual maturation and has been investigated over the course of his disease. In addition to a skull X-ray (normal) and thyroid function tests (normal), a standard insulin tolerance test (insulin 0.15 u/kg) and a standard gonadotropin-releasing hormone (Gn-RH) test (100 microgram Gn-RH i/v) were performed when the bowel disease was in relapse and again during a remission of the bowel disease, achieved by surgery. When the bowel disease was in relapse (coincident with growth arrest) results showed an inadequate release of gonadotrophins and of growth hormone (even after pre-treatment with stilboestrol) but normal release of cortisol and prolactin. During a remission of the bowel disease coinciding with a period of rapid "catch-up" growth, release of growth hormone was normal and that of gonadotrophins supranormal. The demonstration of a reversible apparent partial hypopituitarism in this boy not only re-questions the adequacy of hypothalamic-pituitary function in inflammatory bowel disease but also indicates a potential diagnostic pitfall in the routine investigation of growth retardation if gastrointestinal symptoms are not prominent at presentation.