TABLE 1

Patient’s laboratory test results

Laboratory testResults (reference range)a
Arterial blood gas
 pH7.665 (7.35–7.45)
 Partial pressure of carbon dioxide43.4 mm Hg (35–48)
 Partial pressure of oxygen95.9 mm Hg (83–108)
 Bicarbonate48.4 mmol/L (21–28)
Sodium138 mEq/L (135–145)
Fasting plasma glucose210 mg/dL (70–100)
Magnesium2.2 mg/dL (1.8–2.5)
Thyroid-stimulating hormone2.2 mIU/L (0.4–4.8)
Urine electrolytes, 24-hour
 Potassium117 mmol/24 hours (< 15)
 Sodium86 mmol/24 hours (40–220)
 Calcium172 mg/24 hours (< 228)
 Magnesium84 mg/24 hours (73–122)
Urine creatinine, 24-hour16 mg/kg/24 hours (15–20)
Transtubular potassium gradient9 (< 2 in hypokalemia)
Plasma aldosterone concentration5.24 ng/dL (2.2–35.3)
Direct renin concentration6.09 mIU/L (4.4–46.1)
Serum cortisol
 Measured at 8 AM50.3 μg/dL (6.2–18.0)
 Overnight 1-mg dexamethasone suppression test48.0 μg/dL (< 2.0)
 High-dose (8 mg) dexamethasone suppression test42.7 μg/dL (> 50% reduction from baseline)
Urine cortisol, 24-hour2,800 μg/24 hours (28.5–213.7)
Plasma adrenocorticotropic hormone326 pg/mL (15–65)
  • aResults outside reference range are shown in bold.