Endocrine Abstracts

The leading causes of TBI which may result in pituitary dysfunction are car accidents, falls, sports-related head injuries, violence and war accidents. The prevalence of pituitary dysfunction is approximately 15% following TBI. GH is the most common hormone lost after TBI, followed by gonadotropins (FSH and LH), ACTH and TSH. The proposed pathophysiological mechanisms responsible for the development of pituitary dysfunction after TBI include sella turcica fractures, genetic predisposition, autoimmunity, ischemic changes, hypoxia, increased intracranial pressure, diffuse axonal injury, and persistent neuroinflammation. Recent studies revealed that pituitary dysfunction may also occur in athletes dealing with combative sports including boxing, kickboxing and football. These types of sports are characterized by chronic repetitive head trauma and they are accepted as mild TBI (mTBI) or concussion. The pituitary volume on MRI in retired boxers with hypopituitarism is significantly lower when compared to the boxers with normal pituitary function and healthy subjects. Pituitary dysfunction in TBI victims including athletes may occur during acute phase just after head trauma, it may improve with time or new deficiencies may develop during follow-up. Severity of TBI, patients demographics, radiologic abnormalities and hypopituitarism, ACTH deficiency in particular during acute phase are the risk factors for TBI-induced pituitary dysfunction. Cortisol, thyroid hormone and AVP deficiencies should be investigated during early phase after TBI and screening of gonadotropins and GH is recommended to be delayed 6 to 12 months following TBI. Hypopituitarism may be very easily overlooked because of non-specific or mild symptoms at least in some patients. For this reason, the great majority of the patients suffered from TBI remain undiagnosed and untreated. We recommend an approach to the diagnosis of pituitary dysfunction in the patients with head injury history in routine clinical practice. Treatment of hypopituitarism due to TBI is the appropriate replacement of deficient hormones.