BackgroundThe incidence of adrenal injury after trauma is very rare. Bilateral adrenal injury, which may lead to acute adrenal insufficiency and death, whereas unilateral adrenal trauma is often asymptomatic and masked by injuries to other organs. However, when unilateral adrenal trauma is associated with multiple injuries including brain trauma, critical illness‑related corticosteroid insufficiency (CIRCI) may be present; despite the importance, criteria for the diagnosis are not well established.Case presentationWe report a 16-year-old multi-trauma, brain-injured patient with unilateral adrenal gland injury. An intraparenchymal catheter for intracranial pressure (ICP) monitoring was inserted and craniectomy was performed. Postoperatively, the patient was admitted in the Intensive Care Unit (ICU) under sedation. He presented severe circulatory shock (noradrenaline dose of 1.86 μg/kg/min). which was not reversed despite red blood cell transfusions (noradrenaline increased to 2 μg/kg/min, lactate 1.8-2.1 mmol/L, although Hct was stabilized to 34 g/dl). Empiric hydrocortisone (150 mg intravenously) was administered for suspected adrenal insufficiency, after a blood sample for cortisol levels was drawn. An abrupt improvement in hemodynamics was noted [noradrenaline dose was reduced by half (1 μg/ kg/min) in less than 1 hour, and almost became insignificant during the next 8 hours, while lactate normalized (0.9 mmol/L)]. Hydrocortizone administration was continued for nine days. Fluid balance was restored after the first day. Baseline cortisol levels were 11.45 μg/dl. ICP was steadily less than 20 mmHg. Adrenal hematoma dimensions had increased (4 x 2.7 cm), as seen in the abdominal CT scan performed 9 hours after admission. Twenty days later, a follow up CT scan revealed regression of the hematoma. His remaining ICU course was complicated by fever and sepsis and remained in the ICU for 41 days.ConclusionAlthough, data do not support the use of empiric steroids in trauma patients (with or without brain injury), this case demonstrates that adrenal insufficiency must be considered in the differential diagnosis when shock exists; adrenal gland injury, even unilateral, may play an additional factor. An urgent decision is needed, that can influence outcome.