Syndrome of Inappropriate Antidiuretic Hormone Secretion (SIADH) and Subsequent Central Diabetes Insipidus: A Rare Presentation of Pituitary Apoplexy

Table 1

(a) Standard blood test screen at admission

Na^+	126		(137 - 145)	mmol/l
K^+	3.5		(3.5 - 4.6)	mmol/l
CRP	1.8		(<8)	mg/l
Leucocytes	6.4		(3.5 - 10)	10^9/l
TSH	0.4		(0.3 - 4.5)	10^3 IU/l
T3	3.1		(3.9 - 6.8)	pmol/l
T4	11.4		(12 - 21)	pmol/l

(b) Extended blood and urine tests

Prolactin	1375		(90 - 580)	10^3 IU/l
ACTH	36		(7 - 64)	ng/l
Cortisol 0 min	541			nmol/l
Cortisol 30 min	797		(> 500)	nmol/l
FSH	23			IU/l
LH	6.7			IU/l
Estrogen	<15			pmol/l
IGF-1	192		(70-210)	μg/l
Osmolality	241		(280-300)	mmol/kg
Urine
U-Osmolality	744		(300 - 900)	mmol/kg
U-Na^+	140			mmol/l

Biochemistry: standard blood test screen and extended blood and urine tests. This table shows selected blood sample concentrations from the standard blood test screening performed on the day of hospital admission and the extended blood test analysis performed on day two of admission. Parenthesis illustrates the normal range. = below normal range. = above normal range. CRP= C reactive protein, TSH = thyroid stimulating hormone, T₃= triiodothyronine, T₄= thyronine, ACTH= adrenocorticotropic hormone, FSH= follicle-stimulating hormone, LH= luteinizing hormone, and IGF-1= insulin-like growth factor 1.