Hypogammaglobulinemia (IgG < 4g/L) due to secondary immunodeficiency is common in patients with hematologic malignancies (such as multiple myeloma, or lymphoproliferative disorders). Different societies recommend against the use of immunoglobulin replacement (whether subcutaneous or intravenous) for patients with hematologic malignancies and severe deficiency of Ig in the absence of complications such as recurrent bacterial infections requiring antibiotics or hospitalization. Some guidelines recommend Immunoglobulin replacement with failure of antibiotic prophylaxis or appropriate antibody response to vaccinations. Regardless, these are recommendations based on weak evidence, with lack of clear guidance to dose, when to start or stop treatment. If IVIG is used, the recommended dose is 0.4-0.6g/kg every 4 weeks. Equivalent Subcutaneous Ig dose can be used.
Immunoglobulin replacement has financial and ethical implications without clear positive QoL impact. Canada is the third highest consumer of Ig amongst developed nations with 232g per 1000 population, costing 60,000 to 100,000 CAD annually per patient, placing a significant burden on our healthcare system.
Sources:
Australia National Blood Authority. Acquired hypogammaglobulinaemia secondary to haematological malignancies, or post-haemopoietic stem cell transplantation (HSCT). [Internet]. April 2025 [cited Aug 30, 2025].
National Comprehensive Cancer Network NCCN. Clinical Practice Guidelines in Oncology: Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma. [Internet]. 2021 [cited 2025 Nov].
Otani IM, et al. Practical guidance for the diagnosis and management of secondary hypogammaglobulinemia: A Work Group Report of the AAAAI Primary Immunodeficiency and Altered Immune Response Committees. J Allergy Clin Immunol. 2022 May;149(5):1525-1560. Epub 2022 Feb 14. PMID: 35176351.