The incidence of CD4+ T cell < 300/μL and CD8+ T cell < 400/μL in IPA group was 81.8% (18/22), while the incidences of CD4+ T cell < 300/μL and CD8+ T cell < 400/μL in non-IPA group were 26.7% (12/45) and 24.4% (11/45). This evidence concerns the gene CD4 and Ito hypomelanosis.