Postpartum headache: A broader differential

A 40-year-old female presented to the ED with a history of intermittent headaches since a vaginal delivery 8 days prior. Her pregnancy was unremarkable and was not complicated by pre-eclampsia. She did not present with signs or symptoms consistent with postdural puncture headache or pre-eclampsia. Her delivery was not complicated by hypotension or post-partum hemorrhage. By chance, she was found to be hyponatremic and admitted to internal medicine for further work-up. She was diagnosed with postpartum lymphocytic adenohypophysitis and treated with steroids. She was discharged with a steroid taper and had complete resolution on follow up. Lymphocytic hypophysitis (LH), or commonly known as autoimmune hypophysitis, is a rare inflammatory condition affecting the pituitary gland. Acute LH can result in sudden death as demonstrated in some case reports. The most common symptom in >50% of cases is headache. First-line pharmacological treatment consists of high-dose corticosteroids and is effective in reducing pituitary size and improving endocrine insufficiency in 75% of cases. LH is a potential cause of postpartum headache that can be easily screened for with history and routine bloodwork and has good outcomes with early intervention. LH should be added to the differential for postpartum headaches presenting to the emergency department and routine blood work should be considered for all postpartum headaches.