Screening test for growth hormone deficiency: usefulness of L-dopa-propranolol provocative test

This is a retrospective review of 185 short children who were tested for growth hormone (GH) secretion using the L-dopa-propranolol provocative test. One hundred and thirty-three children were deemed to have passed the screening test when a GH concentration of greater than 15 miu/L was elicited after stimulation. Fifty-two failed the screening test, of which 33 were diagnosed as having growth hormone deficiency (GHD) when they had inadequate growth hormone response to insulin-induced hypoglycaemia. The other 19 were low-responders since they showed adequate GH response to insulin tolerance test (ITT). The low-responder rate to L-dopa-propranolol provocative test among short children who are not GH deficient was 12.5%. The low cost of L-dopa and propranolol, the simplicity and safety of the test, and the acceptable rate of low-responders make the test an effective screening test for GHD.