Recurrent anaphylactic reactions: an uncommon debut of lymphocytic hypophysitis

We report on a 24-year-old male, with exercise-induced asthma and intermittent abdominal pain since puberty, who suffered from recurrent anaphylactic reactions. He also complained of occasional headaches. After extensive studies he was eventually diagnosed with idiopathic anaphylaxis, once the following diagnoses had been excluded: allergic origin [foods (including ω5-gliadin), latex and drugs], hydatidosis, carcinoid syndrome, systemic mastocytosis, autonomic epilepsy, hereditary angioedema, pheocromocitoma, Meckel diverticle, medullar thyroid carcinoma, leukemia, hyper-IgE and hypereosinophilic syndromes. Given the frequency and severity of the attacks, we started off-label treatment with omalizumab, initially well tolerated. Some days after the second dose the patient started to develop recurrent urticaria. Because of these new symptoms, blood work was repeated, and elevated TSH, decreased T4, positive antithyroid antibodies and decreased cortisol levels with normal ACTH were found. The antiadrenal autoantibodies were negative. The MRI showed a slight thickening of the infundibulum, without pituitary adenoma. Suspecting an autoimmune hypophysitis, we looked for antipituitary antibodies; the result was positive. A clinical picture of recurrent anaphylactic reactions, the result of complicated adrenal crises in an asthmatic patient, was a manifestation of lymphocytic hypophysitis, a rare chronic inflammatory disease of autoimmune etiology. One year after replacement therapy had been started, the patient remained asymptomatic.