Hyponatremia Disease Summary

Overview

Hyponatremia is serum sodium concentration <135 mEq/L due to the failure of normal water excretion, as stated in the Introduction section.

Hyponatremia is the most common body fluid disorder and electrolyte imbalance encountered in clinical practice. A detailed discussion about the prevalence of hyponatremia is in the Epidemiology section.

The most common causes of hyponatremia are medication effects, fluid retention, and the syndrome of inappropriate antidiuretic hormone secretion (SIADH), as stated in the Etiology section.  

The Pathophysiology section states that the osmolality (total concentration of solutes in water) of plasma plays a role in the pathophysiology of hyponatremia. The developmental process of hyponatremia is in this section.

The Risk Factors section enumerates the conditions that are associated with the development of hyponatremia.

The Classification section discusses different types of hyponatremia depending on the duration, severity or degree, tonicity, and extracellular volume status.

Hyponatremia_Disease Summary

History and Physical Examination

The Clinical Presentation section describes the clinical features suggestive of hyponatremia in affected patients.

The History section lists the information to be obtained in the evaluation of suspected patients with hyponatremia, while the Physical Examination section enumerates the signs that may be present in these patients.

Diagnosis

The Diagnosis or Diagnostic Criteria section features the essential and supplemental diagnostic criteria in the evaluation of the syndrome of inappropriate antidiuretic hormone secretion (SIADH).

Diagnostic tests that may be requested in patients suspected of hyponatremia are in the Laboratory Tests and Ancillaries section. 

Pseudohyponatremia as a condition that should be ruled out in the diagnosis of hyponatremia is discussed in the Differential Diagnosis section.

Management

Patients with hyponatremia should be assessed for volume status and hyperglycemia, and these are discussed in the Evaluation section.

General measures and treatment goals during hospital admissions in patients with hyponatremia are in the Principles of Therapy section.

The Nonpharmacological section explains the treatment of hyponatremia based on the patient’s extracellular volume status.

The Pharmacological Therapy section discusses treatment options in the management of hyponatremia such as salt tablets, Urea, and vasopressin receptor antagonists.