Essential Diagnostic Criteria for the Diagnosis of Syndrome of Inappropriate Vasopressin release (SIADH)

The following criteria should be met in order to diagnose Syndrome of Inappropriate ADH release

1. Decreased extracellular fluid effective osmolality (<270 mOsm/kg H2O)

2. Inappropriate urinary concentration (>100 mOsm/kg H2O) along with Clinical euvolemia

3. Elevated urinary Sodium concentration (>20 mEq/L) under conditions of a normal salt and water intake

4. Absence of adrenal, thyroid, pituitary, or renal insufficiency or diuretic use