Management of Hyponatremia in Typhoid Fever
The management of hyponatremia in typhoid fever should focus on fluid restriction to 1,000 mL/day for moderate hyponatremia (125-129 mEq/L) and more severe fluid restriction plus albumin infusion for severe hyponatremia (<125 mEq/L), while simultaneously treating the underlying typhoid infection with appropriate antibiotics. 1
Assessment of Hyponatremia Severity
Hyponatremia in typhoid fever should be classified based on severity:
- Mild: 130-135 mEq/L
- Moderate: 125-129 mEq/L
- Severe: <125 mEq/L 1
Management Algorithm for Hyponatremia in Typhoid Fever
Step 1: Assess Volume Status and Severity
- Determine if hyponatremia is hypovolemic, euvolemic, or hypervolemic
- Check serum sodium levels to classify severity
- Evaluate for symptoms of hyponatremia (headache, lethargy, seizures, altered mental status)
Step 2: Manage Hyponatremia Based on Severity
- Mild hyponatremia (130-135 mEq/L): Monitor sodium levels and restrict fluid intake
- Moderate hyponatremia (125-129 mEq/L): Restrict fluid to 1,000 mL/day and discontinue diuretics 1
- Severe hyponatremia (<125 mEq/L): Implement more severe fluid restriction plus albumin infusion 1
Step 3: Correct Sodium Levels Carefully
- Limit correction rate to 4-8 mEq/L per day, not exceeding 10-12 mEq/L in 24 hours 2
- For patients at high risk of osmotic demyelination syndrome (ODS), limit correction to 4-6 mEq/L per day, not exceeding 8 mEq/L in 24 hours 2
- Monitor serum sodium every 2-4 hours during active correction 1
Step 4: Treat Underlying Typhoid Infection
- Administer appropriate antibiotics for typhoid fever
- Ceftriaxone is an effective treatment option for typhoid fever, with dosages of 75 mg/kg/day for children and 4 g/day for adults 3
- Consider azithromycin for multi-drug resistant cases 4
Special Considerations
Risk of Osmotic Demyelination Syndrome (ODS)
Patients with typhoid fever may be at increased risk for ODS due to:
- Malnutrition commonly associated with prolonged illness
- Metabolic derangements
- Possible liver involvement
The risk of ODS may be higher in patients with:
- Advanced liver disease
- Alcoholism
- Severe hyponatremia
- Malnutrition
- Hypokalemia or hypophosphatemia 2
Monitoring During Treatment
- Regular monitoring of serum sodium levels is crucial
- Watch for signs of neurological deterioration that may indicate ODS (dysarthria, dysphagia, oculomotor dysfunction, quadriparesis) 2
- Monitor for improvement of typhoid symptoms (fever, abdominal pain, hepatosplenomegaly)
Case Example
A case report of an 8-year-old girl with typhoid fever presented with hyponatremia along with thrombocytopenia, ascites, and hepatosplenomegaly. She required multiple antibiotics including ciprofloxacin, ceftriaxone, and eventually azithromycin to resolve the infection 4. This highlights the importance of addressing both the electrolyte abnormality and the underlying infection.
Pitfalls to Avoid
Rapid correction of sodium: Avoid correcting serum sodium too quickly, as this increases the risk of ODS, especially in patients with risk factors 2
Inadequate treatment of underlying typhoid: Ensure appropriate antibiotic therapy is initiated promptly, as resolving the infection is crucial for managing associated electrolyte abnormalities 4
Overlooking volume status: Assess whether hyponatremia is hypovolemic, euvolemic, or hypervolemic to guide appropriate management 1
Neglecting monitoring: Regular monitoring of serum sodium levels during correction is essential to prevent complications 1
By following this structured approach to managing hyponatremia in typhoid fever, clinicians can effectively address both the electrolyte abnormality and the underlying infection while minimizing the risk of complications.