Correlation between the number of plasma cells and clinical improvement in retrospective (n = 30, left panels) and prospective (n = 40, right panels) studies.

(A) Strong negative correlation in both studies between the absolute number of IVIg-mobilized plasma cells (PCs) and time to improve one GBS disability-grade. Correlation was analyzed using Spearman test. (B) Day 7 plasmacytosis correlates with faster clinical improvement. Kaplan-Meier analysis of time to one disability-grade improvement following IVIg in relation to day 7 plasma cell counts enumerated on a routine hematology analyzer and confirmed by blood smear exam.