Endocrine Abstracts

Pituitary stalk interruption syndrome presents with a combination of a thin or disrupted pituitary stalk, underdeveloped or absent anterior pituitary, and a missing or ectopic posterior pituitary (EPP) as observed on magnetic resonance imaging (MRI). This condition, a congenital pituitary anomaly, lacks a precise prevalence estimate. In certain instances, the anomaly manifests solely as EPP or pituitary stalk interruption. We report a 5-day-old newborn was admitted due to poor feeding, lethargy, and hypoglycemic seizure. Upon examination, he was found to have undescended testes on one side with a micropenis (SPL 0.8 cm). Laboratory investigations revealed low cortisol levels at 13.4nmol/l (normal range: 82-579nmol/l) alongside decreased growth hormone levels (0.94ng/ml) during hypoglycemia. Additionally, on day 10 of life, serum LH was 0.100IU/l (normal range: 0.3-4.9IU/l), testosterone was 0.00086nmol/l (normal range:2.6-13.8nmol/l), Free T4 was 7.81 pmol/l(normal range: 11.6-29.6 pmol/l), TSH was 5.24U/l (normal range: 0.58-5.57U/l), and Prolactin was significantly elevated at 4293.6microU/l (normal range:less than 212microU/l). Given the markedly high prolactin levels, the possibility of Pituitary stalk interruption syndrome was considered, which was subsequently confirmed by MRI imaging. Clinical exome sequencing was done which revealed PROP 1 gene mutation. Treatment commenced with hydrocortisone replacement initially, followed by thyroid and testosterone replacement. Proposed mechanisms of PSIS encompass mutations in genes implicated in anterior pituitary development, including PIT1, PROP1, LHX3/lHX4, PROKR2, OTX2, TGIF, HESX1, ROBO1, and GPR161. In our instance, genetic assessment revealed a defect in the PROP1 gene. Given the relatively rare occurrence of pituitary stalk interruption syndrome, it is advisable to include magnetic resonance imaging (MRI) of the pituitary when evaluating especially in a newborn with suspected pituitary deficiency to ensure timely diagnosis and treatment. This case report underscores the importance of recognising PROP1 mutations as a potential aetiology for pituitary stalk interruption syndrome, particularly in cases with atypical presentations. Increased awareness of such genetic variations can lead to early diagnosis and appropriate management, thereby improving patient outcomes and guiding genetic counselling for affected families.