Lymphocytic Choriomeningitis Virus–associated Meningitis, Southern Spain - Vol. 18 No. 5 - May 2012 - Emerging Infectious Disease journal - CDC
Volume 18, Number 5—May 2012
Lymphocytic Choriomeningitis Virus–associated Meningitis, Southern Spain
Suggested citation for this article
Lymphocytic choriomeningitis virus (LCMV; family Arenaviridae) is a rodent-borne pathogen; its main reservoir is the common house mouse (Mus musculus), but it has also been detected in pets, research rodents, and wild mice (1,2). Presumed transmission routes to humans are ingestion or inhalation of contaminated rodent feces, urine, or both. Although LCMV usually produces a self-limited mild or asymptomatic infection, it can cause aseptic meningoencephalitis (AME) with teratogenic effects in infants (3). Although LCMV was one of the earliest viruses to be associated with human AME, it is now rarely reported as an etiologic agent (4).
AbstractLymphocytic choriomeningitis virus (LCMV) was detected in 2 patients with acute meningitis in southern Spain within a 3-year period. Although the prevalence of LCMV infection was low (2 [1.3%] of 159 meningitis patients), it represents 2.9% of all pathogens detected. LCMV is a noteworthy agent of neurologic illness in immunocompetent persons.
Historically, in Spain, LCMV was detected in 1 person with encephalitis (5) and 4 persons with meningitis (6). A similar virus, characterized as LCMV lineage IV, was identified in rodents (2).
During 2008–2010, a multicenter project was conducted to investigate viral causes of AME in Spain. The following viruses were considered: human enterovirus (HEV), herpesviruses, Toscana virus (TOSV), mumps virus, phleboviruses, flaviviruses, arenaviruses, and adenoviruses. We report 2 LCMV meningitis case-patients who lived 1,200 meters apart within Granada Province in southern Spain.
The study period was January 2008–June 2010. The population included patients at Hospital Virgen de las Nieves (Granada, Spain) who had suspected AME. Routine virologic investigation included reverse transcription PCR (RT-PCR) of cerebrospinal fluid (CSF) samples for detection of HEV (Xpert EV system, Cepheid, Sunnyvale, CA, USA), TOSV (7), and mumps virus (8), and PCR of herpes simplex virus (HSV) and varicella-zoster virus (LC VHS 1/2 Qual and LC VZV systems, respectively; Roche Diagnostics, Mannheim, Germany). Negative samples were subsequently tested for Epstein-Barr virus, cytomegalovirus, human herpes 6 virus (9), flavivirus (10), arenavirus (2), adenovirus (11), and phlebovirus (12). Specific LCMV RT-PCR was conducted by using a previously described protocol (2). Finally, CSF specimens from PCR-negative case-patients were inoculated in Vero and MRC-5 cell lines for viral culture.
CSF and acute-phase serum samples were also tested for IgG and/or IgM against TOSV (EIA Enzywell Toscana virus IgG/IgM, Diesse, Siena, Italy), West Nile virus (ELISA IgG and IgM-capture ELISA; Focus Diagnostics, Cypress, CA, USA), and LCMV by indirect fluorescent assay (IFA) with further confirmation by Western blot (2).
We studied 159 CSF samples by using PCRs for the presence of HEV, HSV, varicella-zoster virus, TOSV, and mumps virus, yielding 68 positive cases. The remaining viruses were further investigated in the 91 negative samples. A viral agent was detected in 70 (44%) cases: HEV accounted for 44 (63%) of positive cases, followed by varicella-zoster virus in 11 (16%), HSV-1 in 8 (11%), TOSV in 4 (6%), LCMV in 2 (3%), and HSV-2 in 1 (1%).