Masked type 1 diabetes mellitus (T1DM) unveiled by glucocorticoid replacement: a case of simultaneous development of T1DM and hypophysitis in an elderly woman.

As a rare condition characterized by inflammation of the pituitary gland, hypophysitis usually results in hypopituitarism and pituitary enlargement. The most critical outcome of hypopituitarism is caused by secondary adrenal insufficiency. Glucocorticoid deficiency is a life-threatening condition, and patients who develop this deficiency require prompt diagnosis and treatment. However, a delayed diagnosis of hypopituitarism may occur due to its non-specific clinical manifestations. A common presenting sign of glucocorticoid deficiency is hypoglycemia. The amelioration of hyperglycemia has been observed in diabetic patients with adrenal insufficiency. We report the case of a 70-year-old Japanese woman who had suffered from fatigue and anorexia for several months; she was admitted based on refractory hyponatremia (sodium 125-128 mEq/L) and hypoglycemia (glucose 58-75 mg/dL). Laboratory findings and magnetic resonance imaging findings led to the diagnosis of panhypopituitarism caused by autoimmune hypophysitis. After receiving 10 mg/day of hydrocortisone, the patient developed severe hyperglycemia (glucose >500 mg/dL). Undetectable C-peptide levels and positive results of both insulinoma-associated antigen-2 antibodies and insulin autoantibodies indicated that she had experienced a recent onset of type 1 diabetes. The pathophysiological process indicated that overt hyperglycemia could be masked by the deficient action of glucocorticoids even in a diabetic patient with endogenous insulin deficiency. This uncommon case reinforces the importance of the prompt diagnosis and treatment of hypopituitarism. Clinicians should remain aware of the possibility of hidden diabetes when treating hypoglycemia in patients with adrenal insufficiency.

Atypical Familial Mediterranean Fever Complicated with Gastrointestinal Amyloidosis Diagnosed due to Paroxysmal Arthralgia and Intractable Diarrhea, Successfully Treated with Tocilizumab.

A 53-year-old man with recurrent episodes of large joint pain and a low-grade fever at irregular intervals for 16 years developed right knee and ankle arthralgia, watery diarrhea, and abdominal pain. Following an ileum and colon biopsy, he was diagnosed with gastrointestinal amyloidosis. We suspected familial Mediterranean fever (FMF) based on his history and administered colchicine; his symptoms subsequently improved. Thus, he was diagnosed with atypical FMF. After tocilizumab administration, the amyloid deposits disappeared. This case suggests that physicians should consider FMF even in cases with atypical symptoms in order to prevent the progression of amyloidosis and that amyloid deposits can be eliminated by interleukin (IL)-6 inhibition.