%0 Case Reports
%T A CASE OF HYPONATREMIA DUE TO PITUITARY METASTASIS OF LUNG CANCER.
%A Taskaldiran I
%A Gokbulut P
%A Koc G
%A Fırat S
%A Omma T
%A Kuşkonmaz SM
%A Culha C
%J Acta Endocrinol (Buchar)
%V 19
%N 4
%D 2023 Oct-Dec
%M 38933238
%F 1.104
%R 10.4183/aeb.2023.501
%X <B>UNASSIGNED: </B>Hyponatremia is a common electrolyte abnormality.<BR><B>UNASSIGNED: </B>We report a patient who presented with hyponatremia and diagnosed as small cell lung cancer metastatic to hypothalamus and pituitary.<BR><B>UNASSIGNED: </B>A 68 year old male patient was admitted with fever and cough and pneumonia was considered. Serum sodium level was 113 mmol/L. Syndrome of inappropriate ADH (SIADH) is considered. Thyroid function tests and cortisol levels pointed out a central deficiency in both axes. Pituitary MRI was performed and a hypothalamic and pituitary mass were observed. Prednisolone therapy was started followed by L thyroxine replacement. A chest computer tomography (CT) was taken 2 weeks later revealed a mass lesion. Bronchoscopic biopsy was performed and histopathological diagnosis of the tumor was reported as small cell lung cancer.<BR><B>UNASSIGNED: </B>Many mechanisms were considered as the cause of hyponatremia in our patient. SIADH, secondary adrenal insufficiency and secondary hypothyroidism due to pituitary metastasis are possible causes.<BR><B>UNASSIGNED: </B>The reason of hyponatremia is sometimes complex. When the underlying causes of hyponatremia are not evaluated in detail, many diagnoses can be missed.