The significance of quantification of human cytomegalovirus DNA in cerebrospinal fluid and blood for the diagnosis of cytomegalovirus encephalitis in patients with HIV infection

Objective. Determination of diagnostic sensitivity and specificity of human cytomegalovirus (CMV) DNA concentrations in cerebrospinal fluid (CSF), blood leukocytes and blood plasma for verification of CMV-etiology encephalitis in patients with HIV infection.

Materials and methods. 5485 patients with HIV infection hospitalized in Infectious Clinical Hospital № 2 of the Moscow Healthcare Department were followed-up. CNS lesions were diagnosed in 1310 patients. 1667 CSF samples were studied by PCR-RT (RT-PCR-RT) with quantitative determination of CMV DNA, HIV RNA, DNA of pathogens of other neuroinfections; 743 blood serum samples and 3623 plasma samples with quantitative determination of CMV DNA. Reagent kits produced by the Central Research Institute of Epidemiology, Russian Federal Service for Supervision of Consumer Rights Protection and Human Well-Being (Russia) were used. Statistical analysis was performed using Statistica v. 10.0 and SPSSv. 20 statistical software packages, programming language R. The study of relationships was carried out by the analysis of contingency tables using Pearson’s χ2 test. The search for associations between the number of CMV DNA copies in the patient’s biomaterial and the presence of CMV encephalitis was performed using ROC analysis.

Results. Manifest CMVI occurred in 448 (13.4%) patients at the stage of AIDS (3333). CMV encephalitis was diagnosed in 28 patients: 6.3% among patients with CMVI, 0.8% among patients at the stage of AIDS, 4.8% in 584 patients with an established etiology of CNS lesions. The frequency of detection and quantitative indicators of CMV DNA in blood leukocytes, blood plasma and CSF were presented. The absence of CMV DNA or the detection of low virus DNA concentrations in these biomaterials ruled out the CMV nature of the CNS lesion. The presence of CMV DNA in the blood and CSF did not confirm the presence of CMV encephalitis. The concentration of CMV DNA in the CSF, equal to or more than 16,600 copies/ml, blood leukocytes – 4.65 lg copies/105 cells, blood plasma – 62,700 copies/ml, confirmed the CMV etiology of encephalitis with a 95% probability and served as the basis for starting etiotropic therapy.

Conclusion. Quantitative determination of CMV DNA in the CSF and blood samples by PCR does not have an important diagnostic value for the verification of encephalitis of cytomegalovirus etiology in patients with HIV infection.