Based on clinical elements, biological samples (number of leukocytes, erythrocyte sedimentation ratio (ESR), C reactive protein (CRP), serum glucose, blood culture, CD4, viral load (VL), HIV-RNA from cerebrospinal fluid (CSF), etc.), and imagistic evaluation (cerebral magnetic resonance imaging - MRI) the diagnosis of HIV infection stage C3 and HIV encephalitis was established. This evidence concerns the gene CRP and HIV infectious disease.