Endocrine Abstracts

Introduction: Pituitary dysfunction is a recognised complication of traumatic brain injury; it usually involves multiple hormones and can be transient. We present a case of traumatic pituitary haemorrhage resulting in late onset persistent isolated cortisol insufficiency. Case report: A 40 year old man sustained head injury following a road traffic collision. CT brain scan soon after the event was unremarkable. He then developed drowsiness and confusion. MRI scan of the brain suggested pituitary haemorrhage. Pituitary function tests showed low testosterone and LH. Thyroid function, baseline cortisol and prolactin level were normal. He required orthopaedic surgery for other injuries, and was commenced on steroids to cover the peri-operative period, and discharged on oral Hydrocortisone until dynamic pituitary testing. Two Glucagon Stimulation Tests and Short Synacthen Tests 6 and 12 weeks post injury showed normal cortisol and growth hormone responses. The patient was weaned off steroids; however he did not feel well. An Insulin Stress Test performed at 16 weeks revealed cortisol insufficiency with normal growth hormone response. He is currently on maintenance dose Hydrocortisone. Subsequent MRI scans have shown an enlarged pituitary gland with hemosiderin staining in keeping with chronic pituitary haemorrhage. Discussion: This gentleman sustained traumatic pituitary bleeding, following which he developed transient testosterone but late onset sustained cortisol insufficiency. The initially low testosterone level could be explained by the natural physiological response to stress, which mimics secondary hypogonadism. He, therefore, has isolated cortisol deficiency post traumatic brain injury, which has a prevalence of about 1%. He suffered a cortisol crisis during an infection nearly 18 months after the head injury, suggesting the deficiency is permanent.

Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.

Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.

Insulin Stress at 16 Weeks Post Injury