SUN-434 Simultaneously Occurring Suprasellar Tumor and Meningitis: A Rare Cause of Hypopituitarism

Abstract

Background: The most common cause of hypopituitarism is pituitary adenoma. In recent years there is increased reporting of rare causes of hypopituitarism acquired in adulthood, such as other sellar and parasellar masses, brain damage, vascular lesions, infiltrative/immunological/inflammatory diseases and infectious diseases. We report an unusual case of hypopituitarism associated with simultaneously occurring suprasellar tumor and meningitis. Clinical case: A 45-year-old man was brought to the Emergency Department after being found collapsed at his home with a reduced level of consciousness. About 1 week ago, the patient was complaint headache, nausea and vomiting. He had no significant medical history. His initial assessment showed a blood pressure of 130/70 mmHg, heart rate 133/min, and body temperature 38.5 ºC. Initial laboratory finding revealed serum sodium level of 149 mmol/L (135-150), potassium level of 4.3 mmol/L (3.5-5.5), serum osmolality 292 mOsm/Kg (275-295) and urine osmolality 504 mOsm/Kg (400-800). His random cortisol level was 31.8 ug/dl, TSH 0.568 uIu/ml (0.55-4.78), and free T4 10.75 pmol/L (11.5-22.7). From clinical examination and initial investigations, he was diagnosed as having meningitis or encephalitis and was promptly commenced on empirical i.v. antibiotics. The magnetic resonance imaging (MRI) of the brain revealed diffuse leptomeningeal enhancement in both cerebral hemisphere and 1.8*1.5*1.1cm sized, oval-shaped mass in suprasellar portion, which combined peripheral edema. Examination of the cerebrospinal fluid (CSF) following lumbar puncture confirmed meningitis, antibiotics and antiviral agent were continued. After 2 weeks, he suddenly underwent hypotension and polyuria, despite inflammatory markers of blood were improved. Laboratory finding showed serum osmolality 337 mOsm/Kg, urine osmolality 271 mOsm/Kg, serum sodium 153 mmol/L, random cortisol 1.3 ug/dl, and free T4 5.19 uIu/ml. When coupled with the initial results of the brain imaging, this result helped to confirm a hypopituitarism associated with suprasellar tumor and meningitis. The patient's clinical status promptly improved with intravenous hydrocortisone and desmopressin. After that, levothyroxine supplement was started. He had good response to hormone replacement. Conclusion: Hypopituitarism may develop rapidly or slowly depending on the underlying etiology and may involve one, multiple, or all of the pituitary hormones. The clinical presentations of hypopituitarism are usually nonspecific and the recognition of these patients remains the challenge. We emphasize the importance of careful clinical assessment and focused investigations, including cranial imaging and pituitary hormone profiling to establish the underlying diagnosis.