Abstract
We describe a 53-year-old woman with portal-systemic encephalopathy and altered thyroid function. Endocrinological studies revealed low levels offree thyroid hormone with an inappropriately low level of thyroid-stimulating hormone that responded to bolus injection of thyrotropinreleasing hormone with a normal but somewhat delayed pattern. On the diagnosis of hypothalamic hypothyroidism, she was treated with levothyroxine sodium. Thyroid hormone replacement improved not only the symptoms of hypothyroidism but the hyperammonemiaand consciousnessdisturbance, which suggested a hitherto undescribed possibility that hypothyroidism may be an exacerbation factor of hyperammonemia and portal-systemic encephalopathy.
(Internal Medicine 32: 655-658, 1993)
