Isolated ACTH deficiency associated with Crohn's disease

We report a case of a 37-yr-old man with a 11-yr history of Crohn's disease (CD), who presented with mucous diarrheas of 1-week duration and a 3-month history of anorexia, increasing fatigue and weight loss of 7 kg. The patient was treated with sulfasalazine 3g/day until 2 weeks prior to the present admission, when he reduced the dose to half as he considered the drug responsible for his symptoms. Despite aggressive iv rehydration and resolution of diarrheas with an increase in sulfasalazine dose, the patient remained hemodynamically unstable, while laboratory results showed anemia, hypoglycemia, hypertransaminasemia and hyponatremia with marked natriuresis. Thyroid function tests were consistent with primary hypothyroidism, without evidence of autoimmunity. Further laboratory investigation revealed a low basal cortisol and undetectable ACTH with preserved secretory responses of the other trophic pituitary hormones, establishing the diagnosis of isolated ACTH deficiency. Hydrocortisone replacement treatment induced a clinical and laboratory improvement. The autoimmune basis of isolated ACTH deficiency is discussed in association with the presumed contribution of immunologic reactions in the pathogenesis of CD. However more evidence is needed before isolated ACTH deficiency is added to the list of extraintestinal manifestations of CD.