We herein report two cases of primary adrenal insufficiency (AI) associated with antiphospholipid syndrome (APS). In both patients, the main finding that led to the diagnosis was hyponatraemia. The major difference between the two cases was the time at which AI evolved during the course of APS. In the first patient, AI developed acutely along with other presenting features of APS. In the second patient, the AI was unmasked during a stressful situation induced by severe inflammation that occurred 7 years after the first APS manifestation and had probably evolved slowly during the previous few years. These cases emphasise the importance of considering AI in patients with either suspected or newly diagnosed APS as well as in patients who have long been known to have APS. The symptoms and signs alerting the clinician to possible AI are general abdominal complaints, fever, hypotension, and hyponatraemia. Conversely, patients with primary AI should be questioned about the signs and symptoms of APS.
Keywords: Adrenal insufficiency; adrenocorticotropic hormone; antiphospholipid syndrome; hyponatraemia; plasma renin activity; pulmonary embolism; systemic lupus erythematosus.