65 results
Polyuria - Differential Diagnosis Algorithm
Urine Output > 3L /day
Water Diuresis (Urine Osm <100 mOsm/kg)
 • Primary
kg) • Primary Polydipsia ... Central Diabetes Insipidus ... Nephrogenic Diabetes Insipidus
Classification of Diabetes Insipidus

Central or neurogenic diabetes insipidus:
 - Congenital - Structural malformations affecting the hypothalamus
Classification of Diabetes Insipidus ... neurogenic diabetes insipidus ... Nephrogenic diabetes insipidus ... demeclocycline) Primary polydipsia ... #Diabetes #Insipidus
Causes of Polyuria - Differential Diagnosis Algorithm
Polyuria - Urine Output > 3L/day, Increased Urine Volume (>2ml/min)
Osmotic
Test • Primary polydipsia ... Central Diabetes Insipidus ... Nephrogenic Diabetes Insipidus
Polyuria - Differential Diagnosis Algorithm
Polyuria = >3L Urine output / 24 hours
Urine osmolality = 2 (Na
kg • Diabetes Insipidus ... • Primary Polydipsia
Two-step Copeptin algorithm for differential diagnosis of Diabetes Insipidus (DI)

Baseline Copeptin < 21.4 pmol/L:
 • Arginine-stimulated
diagnosis of Diabetes Insipidus ... pmol/L → Primary polydipsia ... DI #Diabetes #Insipidus
Causes of Polyuria - Differential Diagnosis
Excess Intake of Water:
 • Primary polydipsia (a.k.a. "psychogenic polydipsia")
 •
Water: • Primary polydipsia ... "psychogenic polydipsia ... Diabetes Insipidus
Primary Polydipsia
Definition: Excessive volitional water intake
Epidemiology:
 • 6-20% of patients with psychiatric disorders - Most commonly
Primary Polydipsia ... smokers Primary Polydipsia ... Co-morbid diabetes insipidus ... Diagnosis: Diabetes Insipidus ... Alert_Oriented3 #Primary #Polydipsia
Increased Urination - Differential Diagnosis Framework - Increased Volume / Frequency
 • Increased osmotic load (Increased
resistance (Diabetes insipidus ... osm): Primary Polydipsia
Urine chemistry tests for the diagnostic evaluation of a patient with polyuria
UOsm <100 mOsm/Kg (H2O diuresis)
diuresis) • Primary polydipsia ... • Diabetes insipidus
Diabetes Insipidus vs Syndrome of Inappropriate ADH (SIADH) - Comparison Table

Diabetes Insipidus - Inadequate ADH
SIADH -
Diabetes Insipidus ... Table Diabetes Insipidus ... #Diabetes #Insipidus