What is the management for ICPI related hypophysitis?
There is some controversy regarding the optimal management of ICPI-related hypophysitis. Patients with central adrenal insufficiency should be treated with corticosteroids promptly and prior to other replacement hormones, especially thyroid hormone because initial treatment with thyroid hormone may precipitate an adrenal crisis in patients with coexisting impairment of the hypothalamic–pituitary–adrenal (HPA) axis. There has also been debate about whether to treat with high-dose corticosteroids (prednisone 1 mg/kg/day) or physiologic corticosteroid dosing. Recent studies have shown that high-dose steroids fail to promote resolution of pituitary enlargement and pituitary insufficiency and may cause central adrenal insufficiency (if not present before). High-dose steroids could be considered for patients with severe pituitary enlargement, especially if there is a risk for optic nerve compression. Stress dose steroids should be given initially if a patient presents with an adrenal crisis. Patients who have central hypothyroidism (determined by a low serum free thyroxine (T 4 ) level with or without a low total triiodothyronine [T 3 ]) may be placed on thyroid hormone replacement once their adrenal status has been determined to be normal or after corticosteroid replacement has begun. Treatment goals for central hypothyroidism are to maintain serum free T 4 levels in the middle or upper end of the reference range of the particular laboratory assay. Appropriate sex hormone replacement in hypogonadotropic hypogonadism patients (males with testosterone and premenopausal females with estrogen and progesterone as needed) can be considered as well.
It should be noted that in one long-term follow up study (median 33 months), central hypothyroidism resolved in 85% of patients, and hypogonadism resolved in 84% of patients, but corticotroph deficiency was rarely corrected. Therefore, patients with thyroid or gonadal dysfunction should be monitored for recovery if they are asymptomatic or, if started on medication, should later be tapered down or off to see if the respective axes have recovered. Patients with central adrenal insufficiency on physiologic replacement could be rechecked by withholding their steroid dose for 1 or 2 days, followed by measurement of baseline adrenal laboratory values and performance of a cosyntropin stimulation test; however, in most cases, lifelong corticosteroid replacement therapy will be necessary.