Pituitary dysfunction, a relatively common complication of traumatic brain injury in humans, may afflict brain-injured dogs as well. It can go undetected on routine diagnostic testing and contribute to morbidity. Dogs (n = 17) with nonfatal head trauma and associated neurologic dysfunction were included in this study.
Blood collected between <1 and 1460 days posttrauma was assayed for thyroid-stimulating hormone (TSH), total thyroxine (TT4), free T4 (FT4), basal cortisol, endogenous adrenocorticotrophic hormone (ACTH), and insulin-like growth factor-1 (IGF-1). Decreased serum IGF-1 concentration was noted in 7 cases; TT4 and TSH were decreased in 4 cases; and FT4 measured in 3 of these dogs was also decreased. Cortisol and ACTH were undetectable in 2 dogs; an ACTH stimulation test performed on 1 was consistent with hypoadrenocorticism. Both dogs had multiple concurrent deficiencies with associated clinical signs suggestive of panhypopituitarism. The authors conclude that dogs with traumatic brain injury may develop hypothalamic-anterior pituitary dysfunction that might require treatment.
