Endocrine Abstracts

Background: Hyponatremia in not uncommon in elderly. Common causes include medication, heart, kidney and liver diseases, digestive loses, syndrome of inappropriate anti-diuretic hormone. Hormonal imbalances are sometimes overlooked. Sudden onset after a recently invasive procedure could challenge the diagnostic.

Methods: We present a case report of a severe hyponatremia diagnosed after a coronary angiogram. It is a rare case of hypopituitarism secondary to a pituitary macroadenoma.

Case reports: The patient is a 69 years old man that presented in December 2019 in cardiology department for a coronary angiogram. 48 h after angiography the patient was admitted in ICU for severe hyponatremia and rhabdomyolysis – interpreted at the time as side effect to the contrast agent. At that moment he had normal TSH (T4 or T3 were not analysed) and SIADH was infirmed. The adrenal insufficiency was not rule out. Progressively, in the next 6 month the patient presented asthenic syndrome and significant weight loss, which is why he came to our clinic for second opinion. He had a cardiological check-up and an endocrinological exam. The biological evaluation reveals mild hyponatremia, still elevated creatine kinase and also mild anemia. The hormonal profile established the panhypopituitarism and we started substitutive treatment, with rapidly normalisation of biological disturbance. The MRI exam revealed a pituitary macroadenoma, with of the optic chiasm compression, confirmed by visual field.

The patient needed to repeat coronary angiogram for unstable angina and revealed multiple coronary stenosis and 3 active stents were fitted. This time the procedure was performed after Cortisone dose supplementation, without electrolyte imbalance. Considering double antiplatelet therapy after coronary stenting and cardiac risk, the surgical treatment of macroadenoma was scheduled after 6 months, with closely ophthalmologic follow. Transsphenoidal hypophysectomy was successfully performed, and immunohistochemistry diagnosed a non-functional adenoma.

Conclusion: Hormonal imbalance should be suspected in a sudden-onset of life-threatening hyponatremia. Hypopituitarism is a rare cause of hyponatremia and in this case was overlooked, TSH value being normal, without initial testing of T4 and cortisol value. The acute illness and the iodine agent used for angiography revealed long-term hypocortisolemia. A noncardiac surgery could be very challenging in a recently stented patient, due to the risk of bleeding secondary to antiplatelet therapy and treatment discontinuation may lead to perioperative thrombotic cardiac events. In this case the multidisciplinary team was essential for ensuring an excellent outcome.