Infection Prevention

Core Conclusion

Severe infections account for nearly 50% of myeloma deaths in the first 60 days of treatment, requiring mandatory antiviral prophylaxis and emergency medical evaluation within 2 hours of any fever over 38.0°C (100.4°F).

Detailed Points

• (1) Reasons for High Infection Risk: Your immune system is weakened by two main factors. First, the myeloma itself crowds out the healthy plasma cells in your bone marrow that normally produce infection-fighting antibodies (resulting in a condition called hypogammaglobulinemia), making you about 15 times more likely to get an infection than someone without myeloma. Second, powerful treatments like high-dose steroids (dexamethasone), proteasome inhibitors, and newer T-cell redirecting therapies (like CAR-T cells) further suppress your immune system and lower your protective white blood cell counts.
• (2) Shingles (Herpes Zoster) Prevention: Certain myeloma drugs—especially proteasome inhibitors (like Velcade/bortezomib) and monoclonal antibodies (like Darzalex/daratumumab)—can wake up the dormant chickenpox virus in your body, leading to a painful rash called shingles. To prevent this, your doctor will prescribe antiviral pills, usually Acyclovir (400 to 800 mg twice a day) or Valacyclovir (500 mg once or twice a day). You will typically take these for at least 3 months after finishing treatment, but if you are receiving CAR-T or bispecific therapies, you may need to take them for a year or indefinitely.
• (3) Emergency Protocols for Febrile Neutropenia: If your white blood cells are severely low (neutropenia) and you develop a fever over 100.4°F or 100.5°F, shaking chills, or shortness of breath, this is considered a medical emergency. You must contact your care team or go to the hospital immediately. The emergency protocol requires doctors to rapidly take blood and line cultures, and then immediately start you on empirical broad-spectrum intravenous antibiotics to fight off potentially dangerous bacterial infections.
• (4) Timing for G-CSF and IVIG Use:

  • G-CSF (Growth Factors like Neupogen): If your white blood cells drop dangerously low, your doctor may give you G-CSF injections. These are used to stimulate your bone marrow to produce more infection-fighting neutrophils, particularly if your risk of developing a fever alongside low blood counts is 20% or higher.
  • IVIG (Intravenous Immunoglobulin): This is an infusion of healthy, donor antibodies. It is highly recommended if you suffer from severe, recurrent infections and your IgG antibody levels fall below 400 to 500 mg/dL. It is also routinely prescribed to protect patients undergoing intensive CAR-T or bispecific antibody therapies, usually given at a dose of 0.2 to 0.4 g/kg every 3 to 4 weeks.
• (5) Recommendations for COVID-19 and Flu Vaccinations: Vaccines are your first line of defense. Guidelines strongly recommend receiving the seasonal flu (influenza) vaccine annually, as well as staying up-to-date with COVID-19 vaccinations (including bivalent boosters). An important rule: You must ONLY receive inactivated vaccines; live vaccines (like the MMR vaccine) are dangerous for your weakened immune system and should be avoided. If you have a stem cell transplant or CAR-T therapy, your childhood immunity is wiped out, so you will begin a revaccination schedule roughly 3 to 6 months after your procedure.
• (6) Daily Infection Prevention Measures: You have a lot of power to protect yourself at home! Practice excellent hygiene by washing your hands frequently and immediately cleaning any cuts or scrapes to your skin. When out and about, avoid crowds and people who are sick, and consider wearing a mask. At the dinner table, ensure you thoroughly wash all fruits and vegetables. If you are traveling, stick to bottled or boiled water, avoid raw foods, and ensure all your meat is fully cooked to prevent foodborne illness.

The above content is sourced from the following references

• Practical guidance on the prevention and management of infection in multiple myeloma patients: A case-based approach
• Multiple Myeloma Disease Overview
• Multiple Myeloma Newly Diagnosed
• Patient Handbook
• EHA–EMN Evidence-Based Guidelines for diagnosis, treatment and follow-up of patients with multiple myeloma
• NCCN Clinical Practice Guidelines in Oncology: Multiple Myeloma
• NCCN Guidelines for Patients® Multiple Myeloma
• Singapore Myeloma Study Group consensus guidelines for the management of patients with multiple myeloma