Diagnosis and Management of Secondary Adrenal Insufficiency with Hyperferritinemia

Introduction to Secondary Adrenal Insufficiency

The Endocrine Society recommends that a cortisol response to cosyntropin stimulation be used to diagnose secondary adrenal insufficiency, with a response of >18-20 μg/dL indicating intact adrenal gland function 1
Secondary adrenal insufficiency is characterized by low-normal ACTH levels combined with low baseline cortisol, indicating central (hypothalamic-pituitary) dysfunction 1
The American Association of Clinical Endocrinologists suggests that cortisol deficiency is a primary cause of profound fatigue and weakness in patients with secondary adrenal insufficiency 1

The European Association for the Study of the Liver states that a transferrin saturation of <45% is below the diagnostic threshold for iron overload, making hereditary hemochromatosis or primary iron overload extremely unlikely 2, 3, 1
Over 90% of hyperferritinemia cases with transferrin saturation <45% are due to secondary causes, including inflammation, metabolic syndrome, NAFLD, or chronic disease, according to the American College of Gastroenterology 3, 4
The American College of Physicians recommends that ferritin elevation as an acute-phase reactant rather than true iron overload be considered when transferrin saturation is normal 3, 1

The American Gastroenterological Association advises against diagnosing iron overload based on ferritin alone without confirming transferrin saturation ≥45% 2, 3, 4, 1
The Endocrine Society recommends that phlebotomy therapy not be initiated when transferrin saturation is <45%, as this indicates the ferritin elevation is not from iron overload 3, 4

The American College of Radiology suggests that pituitary MRI be used to evaluate for structural lesions causing isolated ACTH deficiency 1
The American Heart Association recommends that metabolic syndrome components be assessed to explain the hyperferritinemia 3, 4
The American College of Physicians advises against pursuing HFE genetic testing or liver biopsy for iron assessment when transferrin saturation is <45% 2, 3, 1
The Endocrine Society recommends that glucocorticoid replacement therapy be initiated for secondary adrenal insufficiency, and that the underlying cause of hyperferritinemia be addressed by treating metabolic syndrome or inflammatory conditions if identified 1, 3, 4