Congenital Hypopituitarism: Clinico-Radiological Correlation

BACKGROUND: Non-tumoral causes constitute a major group of childhood hypopituitarism. The structural abnormalities of the stalk and the pituitary gland correlate with number and severity of concurrent hormone deficiencies. We describe clinico-radiological correlates in patients with non-tumoral hypopituitarism. PATIENTS AND METHODS: Thirty-one children (23 boys) with congenital hypopituitarism, aged 1-17 years, with a peak GH levels of < 7 ng/ml after two pharmacological stimuli (insulin induced hypoglycemia [IIH] and clonidine) were included in the study. MRI tetrad of absent or hypoplastic pituitary, empty sella, redundant or absent stalk and absent/ectopic posterior pituitary bright spot (EPPBS) was considered as a radiological diagnostic criterion and these abnormalities were correlated with number of hormone deficiencies, severity of GH deficiency and mode of presentation at the time of delivery. RESULTS: Twenty (66%) children had vertex presentation, nine breech, and two children were delivered by lower segment Cesarean section (LSCS). Seven (78%) out of nine in the breech delivery group, 14 (70%) out of 20 in the vertex group and one out of two (50%) in the LSCS group had multiple pituitary hormone deficiencies (MPHD) (p = 0.665). Hypoplastic pituitary gland and posterior pituitary abnormalities were more frequent in patients with isolated growth hormone deficiency (IGHD) as opposed to MPHD (87.5% vs 65.2%, p = 0.08, 63% vs 47%, p = 0.64), whereas empty sella and stalk abnormalities were found more frequently in MPHD than in the IGHD group (76% vs 50%, p = 0.45 and 82.6% vs 37.5%, p = 0.01). Higher frequency of MR abnormalities was found in those with a peak GH response of < 3 ng/ml irrespective of the number of other pituitary hormone deficiencies (82.6% vs 37.5%, p = 0.02). Sixteen patients had MRI tetrad and it was more prevalent in the IGHD than in the MPHD group (75% and 44%, p = 0.01) and correlated with the severity of GH deficiency (r = 0.57, p = 0.01). The imaging abnormalities were also more prevalent in children with breech as compared to vertex presentation and correlated with severity of GH deficiency (100% vs 60%, p = 0.03, r = 0.52). CONCLUSION: Imaging abnormalities are frequent in patients with non-tumoral hypopituitarism and correlate best with severity of GH deficiency rather than number of hormone deficiencies and breech presentation.