Recommended Dose of Intravenous Immunoglobulin (IVIg) for Parvovirus B19
The recommended dose of IVIg for parvovirus B19 infection is 2 g/kg total dose, typically administered over 2-5 days (400 mg/kg/day for 5 days). 1
Dosing Considerations
- Standard dosing for parvovirus B19-related pure red cell aplasia (PRCA) is 2 g/kg total dose, which can be divided over 2-5 days 1, 2
- Daily doses of 1 g/kg or higher are associated with increased risk of toxicity, making the 400 mg/kg/day for 5 days regimen preferable 1
- For severe cases with CNS involvement, higher doses may be considered, similar to other severe infections requiring IVIg 3
- Treatment duration may need to be extended in immunocompromised patients who often require repeated courses 2
Clinical Response and Monitoring
- Hemoglobin levels typically correct within 80 ± 54 days after initiating IVIg therapy 2
- Viral clearance (negative PCR) can be expected between 35-159 days after treatment 2
- Approximately 93% of patients respond to the first course of IVIg, but relapses occur in about 34% of cases, usually around 4.3 months after initial treatment 2
- Monitor both peripheral blood and bone marrow samples for parvovirus B19 PCR, as the virus may persist in bone marrow despite clearance from peripheral blood 4
Special Populations
- In solid organ transplant recipients, the same dosing regimen (2 g/kg total) is recommended for donor-transmitted or de novo parvovirus B19 infection 1, 5
- For neonatal/congenital parvovirus B19 infection, IVIg has shown efficacy in reducing viral copy numbers and restoring erythropoiesis 6
- In patients with T-cell immunodeficiency, higher or more frequent dosing may be required due to impaired B-cell activation and humoral response 4
Potential Adverse Effects
- Common adverse effects include headache and aseptic meningitis 3
- Serious adverse effects can include:
Treatment Algorithm
- Confirm diagnosis: Document parvovirus B19 infection with PCR testing of blood and/or bone marrow and assess for PRCA
- Initiate IVIg therapy: 400 mg/kg/day for 5 days (total 2 g/kg)
- Monitor response: Follow hemoglobin levels, reticulocyte count, and viral PCR
- Consider retreatment: If relapse occurs (typically around 4 months), repeat the IVIg course
- For persistent infection: In immunocompromised patients, maintenance therapy may be required with repeated courses at 3-4 week intervals 4, 2
IVIg therapy remains the cornerstone of treatment for parvovirus B19-associated PRCA, especially in immunocompromised patients, with excellent clinical and virological response rates.