A 72 year old woman with allergic bronchopulmonaryaspergillosis and asthma presented to the emergency departmentwith a two week history of increasing tiredness and shortnessof breath. She had no headache, visual disturbance, abdominalpain, nausea, vomiting, or collapse. Her medication includedSeretide 250 Evohaler (fluticasone 250 μg and salmeterol 25μg) one puff twice daily for four years and inhaled Salbutamol.She had been treated with itraconazole 200 mg daily for twoyears, after unsuccessful attempts to stop this medication dueto recurrence of the disease. She had never required treatmentwith oral corticosteroids. There was no family history ofautoimmune disorders.Observations were stable on admission, specifically no posturalhypotension. General physical examination was unremarkable.There was no hyperpigmentation, visual field defects, or clinicalfeatures of Cushing’s syndrome.Full blood count, serum glucose, renal, and liver function testswere within normal limits. Random serum cortisol (1300 hours)was 4 nmol/L (9 am cortisol range, 138-635). Pituitary profiletests including TSH, FSH, LH, prolactin, and IGF-1 were withinnormal limits for the patient’s age. Adrenocorticotrophichormone was less than 10 ng/L (7-51) and adrenalautoantibodies were negative. Chest radiograph and magneticresonance imaging of pituitary showed no abnormal findings.
Questions1. What is the most likely diagnosis based on the hormoneprofile?2. What is the likely cause of the diagnosis in this case?3. How would you manage and follow up with this patient?