SUMMARY
The response of plasma 11-hydroxycorticosteroids (11-OHCS) to parenteral lysine-vasopressin (LVP) was studied in 47 patients with rheumatoid arthritis, 25 of whom had received long-term oral corticosteroid therapy; the remaining 22 had received no oral corticosteroids at any time, and served as controls. Both groups of patients showed excellent reproducibility of the plasma 11-OHCS response to LVP, when administered intravenously or intramuscularly. Comparable plasma 11-OHCS levels were reached in control patients when the intravenous LVP test was carried out in the morning and in the evening. Criteria of a normal response to both intramuscular and intravenous LVP were defined. In the control group, intravenous infusion of LVP led to a more sustained plasma 11-OHCS response than did intramuscular injection of the same dose. No such differences were observed in the corticosteroid-treated group, but the intramuscular test was subnormal more frequently than the intravenous test.
In the control patients, insulin-induced hypoglycaemia and intravenous LVP led to comparable plasma 11-OHCS response, although a higher mean level at 60 min. was observed in the former. This difference was not observed in the corticosteroid-treated patients.
Direct comparison of these three tests lead to the conclusion that the intramuscular LVP test is more sensitive than the intravenous LVP test, but less sensitive than the insulin hypoglycaemia test, in detecting corticosteroid-induced suppression of hypothalamo-pituitary-adrenal function. The intramuscular LVP test is therefore to be preferred to the intravenous test because of its greater sensitivity, its relative lack of side-effects, and its ease of performance.
Posterior subcapsular cataracts and glaucoma associated with long-term oral corticosteroid therapy. In patients with rheumatoid arthritis and related conditions.