[Levels of lymphocyte subsets, immunoglobulins, and complement C3 and C4 in children with hand-foot-mouth disease]

Objective: To study the clinical value of lymphocyte subsets, immunoglobulins, and complement C3 and C4 in the evaluation of immune status in children with hand-foot-mouth disease (HFMD).

Methods: A total of 282 children with HFMD were enrolled as the HFMD group, and 130 healthy children were enrolled as the healthy control group. The percentages of peripheral CD3⁺, CD4⁺, and CD8⁺ T lymphocytes, CD19⁺ B lymphocytes, and CD56⁺ natural killer cells were measured. The CD4⁺/CD8⁺ ratio was calculated. The levels of immunoglobulin A (IgA), immunoglobulin M (IgM), immunoglobulin G (IgG), and complement C3 and C4 were measured.

Results: The multivariate analysis showed that compared with the healthy control group, the HFMD group had significantly lower percentages of CD3⁺, CD4⁺, and CD8⁺ T lymphocytes and levels of complement C3 and C4 (P<0.05), as well as significantly higher percentage of CD56⁺ natural killer cells and level of IgG (P<0.05). The individual effect analysis showed that the children aged 0-3 years in the HFMD group had a significantly higher CD4⁺/CD8⁺ ratio than the healthy control group (P<0.05); boys aged 0-3 and ≥3 years in the HFMD group had a significantly higher level of IgM than the healthy control group (P<0.05); boys aged ≥3 years and girls aged 0-3 years in the HFMD group had a significantly lower level of IgA than the healthy control group (P<0.05).

Conclusions: Cellular and humoral immunity disorders are observed in children with HFMD. The monitoring of lymphocyte subsets and immunoglobulin levels can provide a laboratory basis for immune status assessment in children with HFMD.