A 12-year-old girl was diagnosed at the age of 3 (2014) with acute lymphoblastic leukemia (ALL) and treated with chemotherapy for 2 years resulting in transient symptomatic HG. No B-cell depleting anti-CD20 MAb therapies prescribed; bone marrow transplant wasn’t indicated after chemotherapy. To date, the patient is in complete remission. In 2017, she developed a new HG associated with a low vaccine response. IgRT was initiated. Despite adequate premedication, the patient developed AE (severe headache, fever, and chills) to several IVIg until she was switched to Iqymune®, which was well tolerated.
Repeated IgRT discontinuation attempts, including summer withdrawal, failed. Exploration revealed a low rate of Memory B cells (CD19+/CD27+) and Class-switched Memory B cells (CD27+, IgM/D-). These rates remained almost unchanged even 5 years after the end of chemotherapy (3 explorations: 2017, 2020 and 2022). No family history of immune deficiency.
To date, the patient is still treated with a monthly infusion of Iqymune® at 0.4g/kg. No infections recorded during this treatment. Discussion In this case, the etiology of the immunodeficiency is not well established. T and B cells were severely affected after ALL polychemotherapy but recovered rapidly after treatment stop. Knowing that chemotherapy is aggressive with risk of mutation, and that a treatment is usually administered before the immune system reaches its maturity (7-8 years of life), a mutation leading to immunodeficiency could not be ruled out. Fever, and chills are frequent in pediatric ALL patients and are related to IgA levels. The low rate of IgA within Iqymune® compared to other Ig could explain the good tolerance toward infusions in this patient (Fig.1).
Conclusion
It could be difficult to discern the relationship between primary and secondary immune deficiencies due to crossover between the two entities. Iqymune® displayed a better tolerability profile than this patient’s previous Ig preparations.