Endocrine Abstracts

Adrenal insufficiency can arise from a primary adrenal disorder, secondary to adrenocorticotropic hormone deficiency, or by suppression of adrenocorticotropic hormone by exogenous glucocorticoid or opioid medications. Immune check point inhibitors (ICI) are reported to cause adrenal insufficiency, but this phenomenon has never been seen with ant-TNF inhibitors. We present a case of a 42-year-old female known to have severe Rheumatoid Arthritis resistant to traditional therapies who was started on Adalimumab (anti-TNF inhibitor) and one week later, presented to hospital with headaches and neck stiffness. She was initially treated as presumed meningoencephalitis but later on had a normal MRI Brain and normal CSF analysis. Due to ongoing dizziness, postural hypotension and episodes of vomiting, a 9 a.m cortisol was requested which came back low at 117 nmol/l (reference 133-537 nmol/l). A Short Synacthen test confirmed adrenal insufficiency (cortisol at 0 mins 40 nmol/l, at 30 mins 228 nmol/l, at 60 min 332 nmol/l). ACTH was found to be low at 2.0 ng/L (reference 10-50 ng/l) but rest of pituitary hormone profile was normal. She was started on oral hydrocortisone and her symptoms and later on biochemical markers improved drastically. This case was discussed in our local Pituitary MDT and with Rheumatology team, and they advocated the concurrent use of hydrocortisone and adalimumab. This case is unique as this phenomenon was never observed with monoclonal antibodies and this is the first ever case of suspected anti-TNF inhibitor induced secondary adrenal insufficiency. The likely explanations are either Adalimumab directly suppressed hypothalamic-hypophysial adrenal axis or caused an infection which resulted in indirect suppression of hypothalamic-hypophysial adrenal axis which ultimately caused secondary adrenal insufficiency. It is unclear how this patient developed secondary adrenal insufficiency, more research is needed in this area.