Primary adrenal insufficiency following traumatic brain injury: a case report and review of the literature.

Primary adrenal insufficiency (PAI) is a relatively rare but serious condition that can lead to signs and symptoms ranging from mild generalized weakness and fatigue to fulminant shock and death. We present the case of a previously healthy 31-year-old man who developed PAI while undergoing rehabilitation after a severe traumatic brain injury (TBI). The patient suffered a TBI with comminuted skull fractures, bifrontal confusions, and bilateral epidural hematomas in a jet-ski accident. Acute hospitalization was prolonged by several medical complications, and the patient was admitted for subacute rehabilitation 1 month after his injury with cognitive deficits, persistent agitation, confusion, generalized weakness, and poor endurance for therapy. His weakness, fatigue, and orthostasis did not improve with attempts at gradual remobilization. The patient also had persistent anorexia, nausea, and hyponatremia despite various treatment regimens. Endocrinology workup showed normal anterior pituitary function but an abnormal response to adrenocorticotropic hormone (ACTH) stimulation, leading to the diagnosis of PAI. The patient was treated with prednisone and fludrocortisone, which resulted in improvement in clinical symptoms followed by rapid gains in all functional areas. No previous descriptions of PAI following head injury were found in the medical literature. It is important for physiatrists to be aware of this entity because symptoms of adrenal insufficiency can be similar to those commonly seen with TBI alone. PAI may also be confused with other endocrine disorders more frequently seen after TBI such as the syndrome of inappropriate antidiuretic hormone secretion. Recognition and appropriate management of adrenal insufficiency can lead to significant clinical and functional gains.