12 results
Physiologic Approach to Hypotonic Hyponatremia
The next time you have a case of hypotonic hyponatremia, give the
, Renal Sodium loss ... , Hypervolemia with ... intake (Primary polydipsia ... #differential # ... diagnosis #table
Cerebral Salt Wasting vs SIADH - Pathophysiology 
1) Neurological event
2) Sodium loss from tubules
3) Naturiesis →
Neurological event 2) Sodium ... → ADH → water reabsorption ... Pathophysiology #diagnosis ... #nephrology #hyponatremia ... #comparison
Hyponatremia - Differential Diagnosis Algorithm
Hypovolemic - Give volume
Hypervolemic (Edematous) - Look for and treat underlying cause
Hyponatremia - Differential ... Hypovolemic - Give ... - Primary Polydipsia ... , SSRIs) - SIADH ... #sodium
Modified Hyponatremia Algorithm
Hypertonic Hyponatremia: Hyperglycemia, Mannitol, Urologic irrigants
Hypotonic Hyponatremia: 
 • ADH ON (UOsm > 100):
ON (UNa < 30): Hypovolemia ... OFF (UNa > 30): SIADH ... 100): Primary polydipsia ... #Algorithm #diagnosis ... #sodium #nephrology
Causes of Hyponatremia - Differential Diagnosis Algorithm
Syndrome of Inappropriate ADH - Euvolemic; no physiologic stimulus to
Causes of Hyponatremia ... - Differential ... Euvolemic; no physiologic ... Malignancy True hypovolemia ... suppression • Primary polydipsia
Causes of Hyponatremia - Differential Diagnosis Algorithm
Syndrome of Inappropriate ADH - Euvolemic; no physiologic stimulus to
Causes of Hyponatremia ... - Differential ... Euvolemic; no physiologic ... Malignancy True hypovolemia ... suppression • Primary polydipsia
Hyponatremia - Differential Diagnosis Algorithm
ADH Independent:
 • Tea and Toast Syndrome, Beer Potomania - Low solute
Hyponatremia - Differential ... ADH Independent ... • Psychogenic Polydipsia ... • Hypovolemic - ... insufficiency, SIADH
Hyponatremia - Differential Diagnosis by Mechanism
Decr Blood Pressure (“Decr Effective Circulating Volume”) 
 - Volume depletion
Hyponatremia - Differential ... Diagnosis by Mechanism ... secretion (SIADH ... failure - Primary polydipsia ... #Causes #Sodium
Hyponatremia - Differential Algorithm
Isotonic Hyponatremia: Hyperlipidemia, Hyperproteinemia, Recent TURP
Hypotonic Hyponatremia: 
 • Hypovolemia: Diuretics/Nephropathies, Vomiting, Diarrhea,
Hyponatremia - Differential ... • Euvolemia: SIADH ... Potomania, Psychogenic polydipsia ... Algorithm #diagnosis ... causes #nephrology #sodium
Primary Polydipsia
Definition: Excessive volitional water intake
Epidemiology:
 • 6-20% of patients with psychiatric disorders - Most commonly
Physiology" • ... diabetes insipidus Differential ... Pseudohyponatremia, SIADH ... , Urine Sodium ... #diagnosis #management