Pituitary stalk interruption syndrome presenting as short stature: a case report

INTRODUCTION: Pituitary stalk interruption syndrome is a rare congenital abnormality of the pituitary that is responsible for anterior pituitary deficiency. It is characterized by a classic triad of interrupted pituitary stalk, absent or ectopic posterior pituitary, and anterior pituitary hypoplasia or aplasia. Clinical presentation varies according to age. In adults it presents as short stature and anterior pituitary deficiency. Without early diagnosis and treatment, mortality and morbidity in these patients is high. Early diagnosis and treatment of this rare disease can prevent permanent short statue of the patient. We report the first case of pituitary stalk interruption syndrome from Pakistan. CASE PRESENTATION: A 17-year-old Pakistani young man presented with short stature and underdeveloped secondary sexual characters. His siblings and parents were healthy, with normal height. An examination showed his blood pressure was 90/60mmHg, and his height, weight, and body mass index were 142cm, 34.5kg, and 17.10kg/m2, respectively. He had no hair growth on his face, axilla, or pubis. His testes were between 1 and 2mL in size, with a 4cm-at-stretch micropenis. His lab investigations showed that his thyroid stimulating hormone (TSH) was 8.58uIU/mL (0.4 to 4.2), his free thyroid hormone level FT4 was 0.46ng/dL (0.89 to 1.76), his prolactin was 21.1ng/mL (3.0 to 14.7), and his baseline cortisol was 0.30ug/dL (4.3 to 22.4). His cortisol level after 60 minutes of cosyntropin injection was 3.5ug/dL (4.3 to 22.4), his insulin like growth factor IGF-1 was 31.56ng/mL (247.3 to 481.7), his testosterone level was under 2.5ng/dL (2 to 800), his follicle stimulating hormone FSH was 0.41uIU/mL (0.0 to 10.0), and his leutinizing hormone LH was under 0.1uIU/mL (1.2 to 7.8). His bone age was 10 years according to the Greulich and Pyle method, as shown by X-rays. The results from his pituitary magnetic resonance imaging scan were consistent with pituitary stalk interruption syndrome. CONCLUSIONS: We describe a young man who presented with short stature and was found to have pituitary stalk interruption syndrome. Despite the fact that this is a rare disorder, it should always be kept in the differential diagnosis of a patient presenting with short stature. Patients with this disease have an excellent opportunity to reach normal height if they present before the joining of epiphyses.