Less known aspects of central hypothyroidism: Part 1 - Acquired etiologies

Central hypothyroidism (CH) is a rare cause of hypothyroidism. CH is frequently overlooked, as its clinical picture is subtle and includes non-specific symptoms; furthermore, if measurement of TSH alone is used to screen for thyroid function, TSH concentrations can be normal or even above the upper normal reference limit. Indeed, certain patients are at risk of developing CH, such as those with a pituitary adenoma or hypophysitis, those who have been treated for a childhood malignancy, have suffered a head trauma, sub-arachnoid hemorrhage or meningitis, and those who are on drugs capable to reduce TSH secretion.

Chronic endocrine consequences of traumatic brain injury - what is the evidence?

Traumatic brain injury (TBI) is a major public health problem with potentially debilitating consequences for the individual. Hypopituitarism after TBI has received increasing attention over the past decade; development of the condition as a consequence of TBI was previously hardly mentioned in textbooks on the subject. Hypopituitarism has been reported in more than 25% of patients with TBI and is now thought to be one of the most important causes of treatable morbidity in TBI survivors. However, most clinicians dealing with neuroendocrine diseases and TBI generally do not see such a high incidence of hypopituitarism. This disproportion is not clearly explained, but recent data indicate that diagnostic testing, which is designed for high-risk populations and not for a cohort of patients with, for example, de novo isolated growth hormone deficiency (the predominant finding in TBI), might have overestimated the true risk and disease burden of hypopituitarism. In this Opinion article, we discuss current recommendations for post-traumatic hypopituitarism in light of recent evidence.