reset osmostat

Etiology

• quadriplegia
• tuberculosis
• pregnancy
• psychiatric disorders
• chronic malnitrition
• old age

Pathology

• downward setting of the osmostat
• lowered osmolality setpoint leads to stable hypo-osmolar hyponatremia

Laboratory

• serum osmolality low after water ingestion, high after water restriction
• serum sodium: hyponatremia
  • mild, asymptomatic hyponatremia stable on multiple measurements

Differential diagnosis

• low solute diet
  • hyponatremia may be more pronounced
  • polydipsia, weight loss diet

More general terms

• osmostat
• sign/symptom

Additional terms

• osmolality (Osm)