HIV co-infection (OR 30.12, P < 0.001), the ratio of CD4+ to CD8+ T-cell counts less than 1 (OR 18.97, P = 0.005), cranial nerve impairment (OR 7.12, P = 0.010), CD8+ T-cell greater than 320 /uL (OR 6.36, P = 0.001), paralysis (OR 6.03, P = 0.007), and cerebral infarction (OR 4.28, P = 0.028) were risk factors for TBM cases with mixed intracranial infections (Table 2; Table S2). The gene discussed is CD8A; the disease is coinfection.