At present, the excessive activation of autoreactive B-lymphocytes in children with HSP is considered to lead to the excessive production of immunoglobulin A antibody, which is the core mechanism of the disease’s pathogenesis [18]; this is consistent with our findings of the highest number of CD3–CD19 + cells in this condition, as compared with IM and P-IM. The gene discussed is CD19; the disease is hereditary spastic paraplegia.