To The Editor: Adrenocortical insufficiency causes various physical symptoms, including weakness, fatigue, and loss of appetite due to cortisol deficiency. It is also known to cause psychiatric symptoms such as depression or apathy. However, there are only a few reports of delirium associated with this insufficiency (1). We present a case of delirium, which was caused by secondary adrenocortical insufficiency because of isolated adrenocorticotropic hormone deficiency.
“Mr. A,” a 74-year-old man without a history of neuropsychiatric disease, complained of diarrhea followed by fatigue and a loss of appetite. A general practitioner found hyponatremia, and an intravenous drip infusion of normal saline solution was performed for 1 week. However, the patient’s fatigue and loss of appetite remained. Two weeks later, he went into a delirious state and was admitted to our psychiatric unit.
On admission, a physical examination revealed weakness of the patient’s extremities. He did not have a history of receiving glucocorticoids or skin and mucosal pigmentation. Blood examinations showed hyponatremia (121 mEq/l), neutropenia, and eosinophilia (white blood cell: 4600/ml [20.3% neutrophils and 8.3% eosinocytes]). Potassium and plasma glucose were within normal limits. These findings led us to consider the possibility of adrenocortical insufficiency, and we consulted an endocrinologist for further evaluation. Additional tests revealed low levels of cortisol (1 mg/dl) and adrenocorticotropic hormone (5.9 pg/ml). The growth hormone, luteinizing hormone, follicle-stimulating hormone, all of the thyroid hormones, and prolactin levels were within normal limits. A quad pituitary stimulation with the corticotropin releasing hormone, growth hormone releasing hormone, thyrotropin releasing hormone, and gonadotropin releasing hormone caused a normal elevation of growth hormone, thyroid-stimulating hormone, prolactin, luteinizing hormone, and follicle-stimulating hormone levels. However, the adrenocorticotropic hormone level remained low. A magnetic resonance imaging study showed no tumor or atrophy of the pituitary. These results excluded panhypopituitarism and led us to diagnose the patient with secondary adrenocortical insufficiency because of isolated adrenocorticotropic hormone deficiency. A daily dose of hydrocortisone (20 mg by mouth) was administered, which resulted in a dramatic improvement of the patient’s consciousness level and hyponatremia, followed by recovery from the delirium in 3 days.
To our knowledge, our case is the second report of delirium associated with adrenocortical insufficiency because of isolated adrenocorticotropic hormone deficiency.
Isolated adrenocorticotropic hormone deficiency is a rare cause of secondary adrenocortical insufficiency generally observed in the elderly. Clinical features overlap greatly in isolated adrenocorticotropic hormone deficiency and Addison"s disease. Since symptoms are nonspecific, diagnosis is often delayed, particularly in the identification of isolated adrenocorticotropic hormone deficiency (2).
In our case, noticing neutropenia and eosinophilia, along with hyponatremia, was the key to the right diagnosis (2). Delirium can be found in adrenocortical insufficiency as well as cortisol excess. Therefore, in patients with delirium, recognizing the potential role of cortisol as a cause is important. If adrenocortical insufficiency lies behind the delirium, cortisol replacement will be the only effective treatment, and dramatic recovery from the delirious state can be expected.
1.Fang VS, Jaspan JB: Delirium and neuromuscular symptoms in an elderly man with isolated corticotroph-deficiency syndrome completely reversed with glucocorticoid replacement. J Clin Endocrinol Metab 1989; 69:1073–1077
2.Arlt W, Allolio B: Adrenal insufficiency. Lancet 2003; 361:1881–1893
The authors report no competing interests.
This letter (doi: 10.1176/appi.ajp.2007.07010193) was accepted for publication in April 2007.