According to the results of research published in Clinical Infectious Diseases, testing plasma for polyomavirus JC (JCV) in patients with progressive multifocal leukoencephalopathy (PML) revealed JCV DNA in 25% of patients with undetectable JCV DNA in the cerebrospinal fluid (CSF).
In this retrospective study, plasma samples collected from 103 patients with PML and from 144 control patients without PML were analyzed for JCV DNA. Plasma samples were collected close to the time of PML onset. The presence of JCV DNA in plasma was compared with JCV DNA in other biological samples, as well as clinical and laboratory parameters and outcomes.
JCV DNA was detected in 48% of plasma samples from patients with PML and 3% of samples from control patients without PML, resulting in a sensitivity of 48% and specificity of 97%. For participants living with HIV (n = 79 with PML; n = 49 without PML), the sensitivity and specificity were 37% and 92%, respectively. For participants who were HIV-negative (n = 24 with PML; n = 95 without PML), the sensitivity and specificity were higher, at 83% and 100%, respectively.
A total of 25% of patients with PML who had undetectable JCV DNA in CSF samples had detectable plasma JCV DNA.
Plasma JCV DNA levels were associated with CSF JCV DNA levels (P <.001), as well as prior treatment with corticosteroids (P =.012). Moreover, in HIV-negative patients, increased plasma JCV DNA levels were associated with disease progression (P =.005). In HIV-positive patients, however, plasma JCV DNA levels were associated with disease progression only in patients receiving antiretroviral therapy (P <.001).
The study authors concluded that “plasma analysis for presence and level of JCV-DNA may provide a useful non-invasive biomarker to complement PML diagnosis in the cases with undetectable CSF JCV-DNA, or when CSF samples are unavailable. Testing for plasma JCV-DNA may also be used as a prognostic marker of aggressive disease in both HIV-negative and [antiretroviral therapy]-treated patients with HIV infection.”
Ferretti F, Bestetti A, Yiannoutsos CT, et al. Diagnostic and prognostic value of JC virus DNA in plasma in progressive multifocal leukoencephalopathy [published online January 15, 2018]. Clin Infect Dis. doi: 10.1093/cid/ciy030