Glucose: A fuel for thought!

It is a privilege and an honour to deliver this, the Turner Gibson Oration for 1989. I chose the title of my lecture because glucose, as the essential substrate for brain function, is indeed the fuel for our thoughts. Although important at all ages, it has a particular significanice for the young child, since a normal supply of glucose is essential to protect brain development and hence the potential for thought in the child's brain. Thus, glucose should have a high priority in our own thinking as paediatricians. With this in mind, the purpose of my lecture is to fuel your own thoughts on your management of children who have disordered glucose homeostasis by examining controversy, challenging current dogma and providing new information.     

Adrenal Cortical Function in Children on Steroids

Adrenal cortical function was assessed in 20 children receiving 2·5 to 10 mg. prednisolone daily, by measuring plasma cortisol levels before and after the administration of the synthetic polypeptide β^1-24, tetracosactrin (Synacthen). 18 of the children were asthmatics, one had nephrosis, and one had dermatomyositis.Adrenal function was classified as (a) abnormal response to tetracosactrin, where basal plasma cortisol and post-tetracosactrin levels did not exceed 6 μg./100 ml.; (b) partial response, where there was a rise of 5-10 μg./100 ml. in plasma cortisol following tetracosactrin but the basal levels (< 10 μg./100 ml.) were below or only slightly above the lower normal limit; (c) normal response, where there was usually at least a doubling of the basal value and an incremental increase of at least 10 μg./100 ml. in the plasma cortisol concentrations following tetracosactrin.All 6 children receiving the higher dosage of 10 mg. prednisolone daily had abnormal adrenal function. 4 receiving the lower dosage of 2·5 mg./day had satisfactory adrenal reserve. Of the 10 children receiving the intermediate dosage of 5 mg. prednisolone daily, 2 had frankly abnormal adrenocortical function, 3 had poor adrenal reserve, and 5 produced good incremental values, though their baseline cortisol levels were low. At the 5 mg. prednisolone dose adrenocortical suppression was not correlated either with duration of therapy or with age.