Management of G6PD Deficiency Crisis
The management of a G6PD deficiency crisis primarily involves immediate discontinuation of the offending agent, supportive care, and specific interventions to address hemolysis while avoiding medications that can worsen the condition. 1
Immediate Management
1. Identify and Remove Triggering Agents
- Immediately discontinue any oxidative medications or foods (fava beans)
- Common triggers include:
- Antimalarials (primaquine, tafenoquine)
- Antibiotics (sulfonamides, nitrofurantoin)
- Analgesics (certain "pain killers")
- Rasburicase
- Fava beans
2. Supportive Care
- Ensure adequate hydration with IV fluids to maintain renal perfusion and facilitate clearance of hemolysis products
- Provide supplemental oxygen as needed
- Monitor vital signs and urine output
- Ensure adequate glucose availability (important for red cell metabolism) 1
3. Laboratory Monitoring
- Serial complete blood counts to track hemolysis progression
- Reticulocyte count
- Lactate dehydrogenase (LDH) levels
- Indirect bilirubin
- Haptoglobin levels (typically decreased)
- Urinalysis for hemoglobinuria
- Renal function tests
Specific Interventions for Hemolysis
For Methemoglobinemia in G6PD Deficiency
- Avoid methylene blue as it is absolutely contraindicated in G6PD deficient patients due to risk of severe hemolytic anemia and paradoxical worsening of methemoglobinemia 1
- Use ascorbic acid (vitamin C) as the treatment of choice:
- Adults: 0.5-1g every 12 hours, 1.5-2g IV, or 5g every 6 hours
- Children: 0.5g every 12 hours or 1g every 4 hours 1
- Consider N-acetylcysteine as adjunctive therapy to enhance reduction and increase intracellular glutathione 1
For Severe Hemolysis
- Exchange transfusion is the preferred option for severe cases (81.6% survival rate in refractory cases) 1
- Blood transfusion may be necessary for significant anemia
- Consider hyperbaric oxygen therapy as an alternative treatment for severe cases 1
Prevention of Complications
Renal Protection
- Maintain good hydration to prevent acute kidney injury from hemoglobinuria
- Monitor renal function closely
Management of Hyperbilirubinemia
- Monitor bilirubin levels, especially in neonates
- Consider phototherapy for significant hyperbilirubinemia 2
Special Considerations
Malaria Treatment in G6PD Deficiency
- Avoid primaquine or limit to 5 days in populations with high G6PD deficiency prevalence 3
- Test for G6PD deficiency before administering primaquine or tafenoquine 3
- For P. vivax with intermediate G6PD deficiency (>30% <70%) and non-Mediterranean variant (A-), consider weekly primaquine (0.75 mg base/kg, maximum 45 mg) for 8 weeks with close monitoring 3
- Do not use tafenoquine if G6PD activity is <70% 3
Perioperative Management
- Screen patients suspected of G6PD deficiency before procedures 4
- Safe medications for pain and anxiety management include:
- Benzodiazepines
- Codeine/codeine derivatives
- Propofol
- Fentanyl
- Ketamine 4
Patient Education and Follow-up
- Educate patients about their condition and provide a list of medications/foods to avoid
- Recommend medical alert identification
- Arrange follow-up to monitor for complete resolution of hemolysis
- Screen family members, especially in X-linked inheritance pattern 4
Cautions
- Most G6PD-deficient individuals are asymptomatic until exposed to oxidative stressors 5
- The severity of hemolysis varies based on the specific G6PD mutation and the nature of the oxidative stress 5
- Mediterranean variant (B-) has a very high risk of severe hemolysis compared to the African variant (A-) 3
- Recent evidence suggests some medications previously thought risky (including nitrofurantoin, ciprofloxacin, and hydroxychloroquine) may be safer than previously believed, but caution is still warranted 6
The most effective management strategy remains prevention by avoiding oxidative stressors, prompt recognition of hemolysis, and appropriate supportive care when a crisis occurs 4.