Dehydration - Differential Diagnosis

Differential Diagnosis

In humans, dehydration can be caused by a wide range of diseases and states that impair water homeostasis in the body. These include:

• External or stress-related causes
  • Prolonged physical activity with sweating without consuming adequate water, especially in a hot and/or dry environment
  • Prolonged exposure to dry air, e.g., in high-flying airplanes (5%–12% relative humidity)
  • Blood loss or hypotension due to physical trauma
  • Diarrhea
  • Hyperthermia
  • Shock (hypovolemic)
  • Vomiting
  • Burns
  • Lacrimation
  • Use of methamphetamine, amphetamine and other stimulants
  • Excessive consumption of alcoholic beverages

• Infectious diseases
  • Cholera
  • Gastroenteritis
  • Shigellosis
  • Yellow fever

• Malnutrition
  • Electrolyte disturbance
    • Hypernatremia (also caused by dehydration)
    • Hyponatremia, especially from restricted salt diets
  • Fasting
  • Recent rapid weight loss may reflect progressive depletion of fluid volume (the loss of 1 L of fluid results in a weight loss of 1 kg (2.2 lb)).
  • Patient refusal of nutrition and hydration
  • Inability to swallow (obstruction of the oesophagus)

Other causes of obligate water loss

• Severe hyperglycemia, especially in diabetes mellitus
  • Glycosuria
  • Uremia
• Diabetes insipidus
• Acute emergency dehydration event
• Foodborne illness