Introduction: Pituitary imaging is important for the evaluation of hypothalamo-pituitary axis defects in patients diagnosed with childhood-onset growth hormone deficiency (CO-GHD). Published evidence shows that there is a close relationship between structural changes in the pituitary gland and growth hormone deficiency.
Aim: To evaluate the relationship between clinical, laboratory and magnetic resonance imaging of the pituitary gland in a cohort of CO-GHD patients during the transition period, and to assess the value of pituitary volume as a diagnostic predictor of persistent GHD.
Methods: Retrospective case review of patients diagnosed with CO-GHD referred to our adolescent unit between 2012 and 2020. Adult GHD (AGHD) was defined as a stimulated GH peak < 3 µg/l. Published normative data on pituitary diameters were used to calculate pituitary volumes.
Patients: The study included data from 102 individuals (75 males) diagnosed with CO-GHD (75 patients with Isolated growth hormone deficiency, IGHD; and 27 with multiple pituitary hormone deficiency, MPHD), who underwent retesting of GH reserve at 18.04 years of age (IQR: 17.1-19.1). Patients who had a history of head injuries or radiation exposure were not included. MRI findings were evaluated in 87 individuals.
Results: AGHD was confirmed in 49 individuals with IGHD (66%) and 23 with MPHD (85%), p: 0.015. In our cohort PG volume was negatively correlated with MPHD (p: 0.006) and persistence of growth hormone deficiency in adulthood (p: 0.024). Having an anatomically normal pituitary gland (PG), did not decrease the likelihood of being diagnosed with ADHD (Table 1). Multivariant analysis of logistic regression suggested that pituitary volume, CO-MPHD and IGF1 (SD) off GH therapy are good predictors of AGHD ([SE 88.5 %, SP 27.3%] p 0.02).
|MRI findings||Non AGHD||AGHD||P value|
|Pituitary volume (SD)||0.3 ±1.28||-0.47 ±1.36||0.024|
|Anatomically normal pituitary gland||56.7 %||73.9%||0.089|
|Abnormal posterior pituitary gland (APP)||20 %||47.8 %||0.009*|
|Combined Small anterior pituitary gland and abnormal posterior pituitary gland||13.3 %||55 %||0.005*|
|Septo Optic Dysplasia||11.53 %||21.3 %||0.28|
|IGF-1 off treatment (SD)||0.73 ±1.31||-0.67 ±2.11||0.001*|
Conclusions: Measurement of pituitary gland volume by MRI combined with IGF-1 concentrations off GH treatment, could help clinicians to rationalise the extent of GH axis re-assessment in patients with IGHD/MPHD at transition.
22 Sep 2021 - 26 Sep 2021