Which endocrine disturbances can follow TBI?

• A. Diabetes insipidus and SIADH with dysnatremia
• B. Hyperthyroidism and hypogonadism
• C. Hypercalcemia
• D. Addison disease

Answer: (A)

The key idea is that injuries to the hypothalamic–pituitary axis after brain trauma commonly disrupt ADH regulation. This can produce two classic problems: diabetes insipidus, from a deficiency of antidiuretic hormone, and SIADH, from inappropriately excessive ADH release. Diabetes insipidus causes polyuria with risk of dehydration and tends to lead to high serum sodium (hypernatremia) if not matched by water intake. SIADH causes water retention with dilutional hyponatremia, leading to low serum sodium. The combination of DI and SIADH with dysnatremias is a well-recognized endocrine consequence after traumatic brain injury.

Other endocrine issues like hyperthyroidism or hypogonadism, adrenal insufficiency (Addison disease), or hypercalcemia can occur with pituitary or hypothalamic injury but are not as characteristic or as common in the acute post‑traumatic period as DI and SIADH with dysnatremia.