Compared with PCP-, CD4+(%) was positively correlated with pulmonary Roving cocci, negatively correlated with intestinal Ruminococcaceae_UCG-003, Prevoella 9, Christensenellaceae_unclassified, Eggerthellaceae_unclassified, and g_Caproiciproducen in PCP. This evidence concerns the gene CD4 and pneumocystosis.