Primary Polydipsia
Definition: Excessive volitional water intake
Epidemiology:
• 6-20% of patients with psychiatric disorders - Most commonly schizophrenia (10-20%)
• Other associations: affective & anxiety disorders, anorexia nervosa, & developmental disabilities
• Symptomatic hyponatremia occurs in only 2-5%
• 70% of pts are tobacco users; in one study, all of those with symptomatic hyponatremia were heavy smokers
Primary Polydipsia Physiology"
• Malfunction of hypothalamic thirst center
• ADH suppression and Thirst set points are different - Thirst persists even with suppressed ADH
• Suggested explanations:
- Hippocampal neuroendocrine dysfunction
- K+ deficits impairing urine concentrating abilities
- Co-morbid diabetes insipidus
Differential Diagnosis: Diabetes Insipidus, Impaired Urinary Dilution, Pseudohyponatremia, SIADH, MDMA intoxication
Initial Workup: Serum Osm, Urine Osm, Serum Sodium, Urine Sodium
By @Alert_Oriented3
#Primary #Polydipsia #diagnosis #management #nephrology
