CD8A and pneumocystosis: In HIV-negative patients with PCP, the presence of a CD8+ T cell count ≤300/μL (p = 0.015, OR = 11.526, 95% CI = 1.597–83.158) and a demand for mechanical ventilation (p < 0.001, OR = 33.578, 95% CI = 8.056–139.950) were independent predictors of 3-month all-cause mortality.