Medical Journal of Zambia, Vol. 46 (4): 277 - 285 (2019) Original Article A Study of the John Cunningham Virus (JCV) Seroprevalence among Zambian Adults presenting with “Meningoencephalitis” to the University Teaching Hospital, Lusaka, Zambia 1A. Patel, 2S. Lakhi, 1, 3 O. Siddiqi, 4I. Koralnik 1 University of Zambia, School of medicine, Department of Internal Medicine, Lusaka, Zambia 2 University Teaching Hospital, Department of Internal Medicine, Lusaka, Zambia 3 Department of Neurology, Beth Israel Deaconess Medical Centre, Boston, USA 4 Department of Neurological Sciences, Rush University Medical Centre, Chicago, USA ABSTRACT Results: Final analysis for JCV seroprevalence was done in 96 patients and noted to be 46% (95% CI, Background: The John Cunningham virus (JCV) is 35.62 – 56.31). The JCV seroprevalence in the HIV an opportunistic virus which leads to the positive group was 40.82% and in the HIV negative development of progressive multifocal group was 51.06 % but there was no statistical leukoencephalopathy (PML), which is a lytic difference (p-value 0.31). None of the other factors infection of oligodendrocytes of the central nervous studied had any impact on the JCV seroprevalence system in immunosuppressed patients. Infection such as age, gender, clinical presentation, CD4 with the JCV occurs in childhood and the virus count and co-morbid TB meningitis (TBM) remains quiescent in the body, activating during diagnosis. There was a bimodal distribution of age immunosuppression. Exposure to the virus can be associated with JCV seropositivity; with one peak detected by testing for JC virus specific antibodies in occurring in the 18 to 20 years age group and the an ELISA test. Our aim was to determine the JCV second peak occurring in the 55 to 60 years age seroprevalence and factors associated with its group. 14 (3.2%) confirmed PML cases, based on positivity among Zambian adults presenting to the clinical features and JCV DNA CSF positive, were University Teaching Hospital (UTH) with suspected all JCV seropositive and HIV positive with meningoencephalitis and to assess the JCV ELISA advanced immunosuppression (CD4<200/mm3). test as a possible tool for PML risk stratification. Memory impairment was associated with a 6 fold Methodology: This was a cross sectional nested increased likelihood of having PML in advanced study in the TB meningitis in Zambia (TMZ) study HIV disease with JCV seropositive patients which which looked at improving ways of TB diagnosis in further, increased to over 20 fold after adjusting for patients with meningoencephalitis. It included age , gender and TBM diagnosis. After adjusting for adults 18 years and older who presented with other variables TBM was associated with an 87% suspected meningoencephalitis and had undergone a less likelihood of having PML (p-value 0.03). lumbar puncture as part of their evaluation. 50 HIV Female gender was associated with increased risk of positive and 50 HIV negative patients were selected having PML (p-value 0.02) and a younger age was from the parent study and underwent testing for JCV protective for PML (p-value 0.03). serology. PML cases were also recruited from the parent study based on clinical features, confirmed by Key words: John Cunningham Virus (JCV), JCV DNA PCR of CSF. Progressive Multifocal Leukoencephalopathy (PML), seropositive 277 Medical Journal of Zambia, Vol. 46 (4): 277 - 285 (2019) Conclusion: The prevalence of anti-JCV antibodies HIV+ Zambian adults (COINZ), JCV DNA was in patients with suspected CNS infection detected in 20/331 (6%) of CSF samples of HIV+ (meningoencephalitis) was 46%. Anti- JCV Zambians presenting with signs and symptoms antibody prevalence did not differ significantly by consistent with CNS infection. 10 age, gender, HIV status or CD4 count. Memory impairment in JCV seropositive, advanced HIV Explanations for the paucity of reports of PML from disease patients with meningoencephalitis was the Africa include non-recognition of the condition, diagnostic challenges, death due to other infections most important variable associated with having which occur at higher CD4 counts such as TB, as PML. well as suggestions of decreased seroprevalence and INTRODUCTION neurovirulence of African JC virus types. 11, 12 The John Cunningham virus (JCV) is an In this study, we sought to determine the opportunistic virus, which causes progressive seroprevalence of JCV amongst the Zambian multifocal leukoencephalopathy (PML).1 PML is a population who present with features of a central n e r v o u s s y s t e m ( C N S ) i n f e c t i o n lytic infection of mainly oligodendrocytes of the (meningoencephalitis) and factors associated with central nervous system in immunosuppressed JCV seropositivity. We also assessed the possible 2 patients. The JCV is a ubiquitous human pathogen role of the JCV antibody test in stratifying PML risk and exposure is unavoidable. After asymptomatic in affected populations, as PML is a fatal disease primary infection with the JCV in childhood, the with a 9% survival rate at 1 year without any virus remains quiescent in the kidneys, bone intervention.2 Therefore, early identification is key. marrow, and lymphoid tissue and becomes activated 3, 4, 5 METHODOLOGY when the host becomes immunosuppressed. This was a cross sectional study nested in the TB Once infected, exposure to the virus can be detected by testing for JC virus specific antibodies and meningitis in Zambia (TMZ) study, which was antibody tests for the JCV are now successfully carried out at UTH over a period of 3 years (2015 – being carried out to determine the subsequent risks 2018). The TMZ study looked at improving ways of of developing PML in at risk populations.6 diagnosing TB meningitis in the Zambian population who presented with signs and symptoms One of the major unanswered questions of JC virus consistent with a CNS infection. It consisted of 550 epidemiology is whether it is less frequent in Africa patients, ages 18 and older, divided into HIV than in the West. While multiple studies have shown positive and HIV negative groups who had that about 55% of adult are JCV seropositive in presented with features of meningoencephalitis and Europe and the US nothing is known about JCV had received a lumbar puncture as part of their seroepidemiology in Africa.7 evaluation. With the advent of the HIV pandemic, and the Participants increasing use of immunosuppressive agents, the incidence of PML has risen sharply, but very few 100 patients were selected, divided into 50 HIV cases from Africa have been reported. Two cases of positive and 50 HIV negative patients from the 2 PML have been diagnosed by autopsy among HIV+ arms of the TMZ study, for determining JCV patients in Uganda and Gambia each. 8, 9 PML seroprevalence. prevalence in an autopsy series from Ivory Coast, conducted on 271 HIV positive patients who died 14 confirmed PML cases based on clinical, from any cause within the study period, was 1.5%. 9 laboratory and radiological criteria (American In the study of CNS opportunistic infections in Academy of Neurology criteria) were also selected from the TMZ study for the purpose of assessing 278 Medical Journal of Zambia, Vol. 46 (4): 277 - 285 (2019) PML risk in affected populations. 13 Participants prevalence and prevalence by demographics and were selected from the inpatient and outpatient clinical characteristics. Our study sample was medical wards at UTH adult hospital. compared to the parent TMZ study using Chi square tests. Factors associated with JCV seroprevalence Procedure were analysed using multiple logistics regression Sampling of the participants was done by selecting using odds ratio as a measure of association. the first consecutive 50 HIV negative patients The multiple logistic regression model was also used recruited in the TMZ study which met the inclusion for PML risk stratification by comparing the criteria. The HIV positive group was then matched advanced HIV JCV seropositive patients with the based on gender and age. The PML patients were PML patients in the initial model and then selected based on convenience sampling as PML comparing only the borderline insignificant was noted to be relatively rare. variables in the final model (p-value £ 0.06). At the time of enrollment of the TMZ study, a Ethical approval detailed history and a full neurological examination was performed on all participants by the attending Ethics approval was obtained from the University Of neurologist. Patients who had already received a Zambia School Of Medicine Biomedical Research lumbar puncture as part of their routine evaluation Ethics Committee and the Director of UTH were asked if excess CSF be used as part of this (IRB00001131 of IORG0000774). Written study. The CSF from all HIV positive and HIV informed consent was obtained from each of the negative underwent qualitative testing to detect the participants or the next of kin. presence of JCV by using DNA PCR (Qiagen molecular kit). Those with a positive JCV DNA in RESULTS CSF were diagnosed as PML together with a Patient Characteristics compatible clinical and radiological picture. A blood sample was also collected from the 100 patients were selected from the parent TMZ consenting patients and a CD4 count done on all the study. The selection was matched for age and gender. participants. The remaining blood was stored and Table 1 shows the characteristics of our study sera aliquoted and kept frozen at -20 C. Frozen sera sample. 26 (26%) had a confirmed diagnosis of was sent to the German Cancer Research Centre TBM. (DKFZ) in Heidelberg, Germany and JCV serology was performed using commercial JCV ELISA TABLE 1: Characteristics of the Patients (Quest Diagnostics). The samples were analysed at a VARIABLE JCV STUDY dilution of 1:10000 and an antibody titre to the JCV N (%) capsid (VP1) >70 indicated JCV seropositivity.