CD79A and lymphopenia: The presence of lymphopenia at the time of vaccination was also a significant predictive factor for decreased humoral response (OR: 3.5, 95% CI: 1.8–6.7, p = 0.019), as well as the low levels of IgA (OR: 2.9, 95% CI: 1.8–4.4, p = 0.024).