In previous studies, the median CD4 level in non-HIV patients at PCP diagnosis was 61 to 329 cells/μL, which was higher than the level in HIV patients (< 50 cells/μL), and > 35% of these non-HIV patients had CD4 > 300 cells/μL [3, 14, 24, 25]. Here, CD4 is linked to pneumocystosis.