Pediatric Hyponatremia Clinical Presentation

Updated: Apr 26, 2014
  • Author: Muthukumar Vellaichamy, MD, FAAP; Chief Editor: Timothy E Corden, MD  more...
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The history of patients with hyponatremia may include the following:

  • Hypotonic fluid use for maintenance hydration in hospitalized children (potential risk factor)

  • Feeding with hypotonic formula or excessive free water during infancy

  • Conditions that cause GI, Na-rich fluid loss, including the following:

    • Diarrhea

    • Vomiting

    • Fistulas

  • Renal disorders, including the following:

    • Salt-losing nephropathy

    • Acute renal failure

    • Chronic renal failure

  • Postoperative states [5]

  • Psychiatric conditions

  • Coma

  • Drug use

  • CNS and pulmonary diseases

  • Cirrhosis

  • Congestive heart failure

  • Acquired immunodeficiency syndrome (AIDS)



CNS findings

See the list below:

  • Early signs include the following:

    • Anorexia

    • Headache

    • Nausea

    • Emesis

  • Advanced signs include the following:

    • Impaired response to verbal stimuli

    • Impaired response to painful stimuli

    • Bizarre behavior

    • Hallucinations

    • Obtundation

    • Incontinence

    • Respiratory insufficiency

    • Seizure activity

  • Far-advanced signs include the following:

    • Decorticate or decerebrate posturing

    • Bradycardia

    • Hypertension or hypotension

    • Altered temperature regulation

    • Dilated pupils

    • Seizure activity

    • Respiratory arrest

    • Coma

Cardiovascular findings

See the list below:

  • Hypotension

  • Tachycardia

Musculoskeletal findings

See the list below:

  • Weakness

  • Muscular cramps



Hypervolemic hyponatremia (excess free-water retention)

See the list below:

  • Congestive heart failure

  • Cirrhosis

  • Nephrotic syndrome

  • Acute or chronic renal failure

Hypovolemic hyponatremia due to renal loss of sodium in excess of free-water

See the list below:

  • Diuretic excess

  • Osmotic diuresis

  • Salt-wasting diuresis

  • Adrenal insufficiency

  • Pseudohypoaldosteronism

Hypovolemic hyponatremia due to extrarenal loss of sodium in excess of free-water

See the list below:

  • GI conditions, such as the following:

    • Vomiting

    • Diarrhea

    • Drains

    • Fistula

  • Sweat

  • Cystic fibrosis

  • Cerebral salt-wasting syndrome (CSWS)

  • Third-spacing conditions, such as the following:

Normovolemic hyponatremia

See the list below:

  • Syndrome of inappropriate antidiuretic hormone secretion (SIADH)

    • Tumors - Adenocarcinoma of the duodenum, adenocarcinoma of the pancreas, carcinoma of the ureter, carcinoma of the prostate, Hodgkin disease, thymoma, acute leukemia, lymphosarcoma, or histiocytic lymphoma

    • Chest disorders - Infection (eg, tuberculosis or bacterial, mycoplasmal, viral, or fungal infection), positive-pressure ventilation, decreased left atrial pressure (eg, due to pneumothorax, atelectasis, asthma, cystic fibrosis, mitral valve commissurotomy, ligation of the patent ductus arteriosus ligation), or malignancy

    • CNS disorders - Infection (eg, tuberculous meningitis, bacterial meningitis, encephalitis), trauma, hypoxia-ischemia, psychosis, brain tumor, or miscellaneous CNS disorders (eg, Guillain-Barré syndrome, ventriculoatrial shunt obstruction, acute intermittent porphyria, cavernous sinus thrombosis, multiple sclerosis, anatomic abnormalities, vasculitis, stress, idiopathic causes)

    • Drugs (see image below)

      Drugs that impair water excretion. Drugs that impair water excretion.
  • Reset osmostat

  • Glucocorticoid deficiency

  • Hypothyroidism

  • Water intoxication due to intravenous (IV) therapy, tap-water enema, or psychogenic water drinking