Correlations between inflammatory response and lymphocyte percentage or CD19+ B cell count in Kawasaki disease children at different ages undergoing intravenous immunoglobulin: a retrospective study

Abstract

Background: Immunoglobulin Intravenous (IVIG) widely used in Mucocutaneous Lymph Node Syndrome (Kawasaki disease, KD). However,patients’inflammatory response remains unclear during usage. We evaluated the relationship between inflammatory response and lymphocytes count in KD children with different ages undergoing IVIG to identify the clue significance of lab parameters in therapeutic effect. Methods: We retrospectively reviewed the medical records of 60 KD children and divided them into five groups depending on ages. We investigated all patients’reduced neutrophil percentage and increased lymphocyte percentage before and after IVIG. In the group of patients aged 4 years and older, we explored the absolute counts of CD19 + B cell before therapy and analyzed it together with patient selves’level of interleukin-10 (IL-10) after IVIG. Results: In KD patients after the treatment of IVIG, The means of decreased neutrophil percentages and increased lymphocyte percentage are respectively 30.92% and 25.25% (group of less than 1 year), 29.52% and 22.14% (1 year), 28.31% and 21.7% (2 years), 32.42% and 25.98% (3 years), 34.58% and 27.92% (4 years and older). The scatter diagrams of these two indexes in all groups showed linear relationship. The correlation coefficients valued respectively 0.91, 0.87, 0.91, 0.97, and 0.99 with p value less than 0.01 in all of groups. Means of age correlated positively with their correlation coefficients (r = 0.88, P < 0.05). In the patients aged 4 years and older,absolute counts of CD19 + B cell before IVIG increased, which presented a linear correlation with the decreased extent of IL-10 after the IVIG (r = 0.71, P < 0.05). Conclusions: The older the children’s age, the better the regulatory effect of IVIG on the KD children's immune response and on the recovery of immune equilibrium. In KD patients aged 4 years and older, the abnormally proliferating CD19 + B cell may take part in the enhanced secretion of IL-10 to balance the overactive humoral immune. In patients 4 years and older, combining absolute count of CD19 + B cell before IVIG with the extent of decreased IL-10 after IVIG may have potential significance to evaluate the effect of IVIG on inflammatory immune response.