Nupur Bathwar, Satyendra Batra, Arjun Kurup, Jagdish Prasad Meena, Rakesh Kumar Deepak, Pranay Tanwar, Deepam Pushpam, Poonam Coshic, Sujata Mohanty, Sameer Bakhshi, Rachna Seth, Aditya Kumar Gupta
Pediatric ASCT recipients demonstrated predictable immune recovery; hypogammaglobulinemia at three months was confined to rituximab-exposed patients, supporting risk-stratified post-transplant immunoglobulin surveillance and revaccination.
OBJECTIVES: To determine the prevalence of hypogammaglobulinemia at three months post-ASCT and characterize humoral and cellular immune reconstitution kinetics.
METHODS: Twelve pediatric patients (median age 10 y) undergoing ASCT for high-risk neuroblastoma (n = 4) or relapsed / refractory Hodgkin lymphoma (n = 8) at AIIMS New Delhi (February 2024-November 2025) were prospectively followed. Serial immunoglobulin levels and lymphocyte subsets were measured at baseline and on days +15, +30, +90, +180. Linear mixed-effects models analyzed trajectories on percentages and absolute counts.
RESULTS: Median IgG at day +90 was 1070 mg/dL (IQR 901-1244). Hypogammaglobulinemia (IgG <500 mg/dL) occurred in 2 of 12 patients (16.7%; 95% CI: 2.1-48.4); both had received rituximab pre-transplant. None of the nine rituximab-naïve patients developed hypogammaglobulinemia. IgM showed a non-significant upward trend at day +90 (p = 0.054), reaching significance at day +180 (p <0.05). Absolute-count analysis demonstrated CD8+ expansion at day +30 (Δ = +652 cells/µL; p = 0.001), profound B-cell depletion at days +15 and +30 (both p <0.01), and a CD4+ deficit at day +90 (Δ = -198 cells/µL; p = 0.017). NK-cell counts remained stable.
CONCLUSIONS: Pediatric ASCT recipients demonstrated predictable immune recovery; hypogammaglobulinemia at three months was confined to rituximab-exposed patients, supporting risk-stratified post-transplant immunoglobulin surveillance and revaccination.