Having compared variables such as age, gender, CD4 T-lymphocyte count at the time of hospitalisation, number of years since diagnosis of the infection, transmission route, ARV treatment, and death during hospitalisation among patients with the most commonly diagnosed CNS opportunistic conditions, i.e., toxoplasmosis, cryptococcosis, and PML, there was no statistically significant differences with regard to those variables (Table 8 and Table 9). The gene discussed is CD4; the disease is infection.