Background: Re-evaluation of the diagnosis of GHD at the completion of linear growth is a key task.
Objectives: To audit the impact of consensus recommendations on diagnosis of GHD and initiation of GH therapy in adolescents previously treated for a brain tumour (BT) or haematological malignancy (HM).
Population: Sixty one patients who had received GH therapy until final height following treatment for a BT (n=40) or a HM (n=21) were identified and would be considered within a high likelihood category for retesting as GHD (initial IGF-I test, followed by GH test if IGF-I > −2SDS). Of the BT patients 20 had involvement of the hypothalamic pituitary axis (BTHP) and had >3 other pituitary deficits, and by guidelines would not require retesting. Twenty had tumours distant from the HP axis (BTD).
Results: Of the 61 patients, three patients did not attend for retesting. All 20 BTHP patients were eligible for continuous GH therapy without retesting; however, seven were tested, with all except one fulfilling the criteria for GHD (IGF-1 SDS <−2 or peak GH <5 mcg/l). Of the 20 BTD patients 13 had IGF-1 measurements, 7 of whom had an IGF-1<−2 SDS, 5 of these underwent GH provocative testing, all of whom had GH levels of <5 mcg/l. Nine others were diagnosed as GHD on provocative testing. In contrast, of the 21 patients with HM 15 patients had IGF-1 measurements, only one of whom had a level <−2 SDS. Ten were diagnosed as GHD on provocative testing.
After retesting, 46 out of 58 patients were eligible for GH therapy in the transition period. However only 25 eligible patients (54%) restarted or continued GH therapy.
Conclusions: Current guidelines are effective for identifying patients with high likelihood of GHD (IGF-I levels in BT patients), but HM patients require IGF-I and GH testing. However our current endocrine care is failing to educate and encourage adolescents with GHD to restart GH therapy after the completion of growth.