Viral infections of the central nervous system in Spain: A prospective study

Abstract

The aim of the study was to determine the incidence of viruses causing aseptic meningitis, meningoencephalitis, and encephalitis in Spain. This was a prospective study, in collaboration with 17 Spanish hospitals, including 581 cases (CSF from all and sera from 280): meningitis (340), meningoencephalitis (91), encephalitis (76), febrile syndrome (7), other neurological disorders (32), and 35 cases without clinical information. CSF were assayed by PCR for enterovirus (EV), herpesvirus (herpes simplex [HSV], varicella-zoster [VZV], cytomegalovirus [CMV], Epstein-Barr [EBV], and human herpes virus-6 [HHV-6]), mumps (MV), Toscana virus (TOSV), adenovirus (HAdV), lymphocytic choriomeningitis virus (LCMV), West Nile virus (WNV), and rabies. Serology was undertaken when methodology was available. Amongst meningitis cases, 57.1% were characterized; EV was the most frequent (76.8%), followed by VZV (10.3%) and HSV (3.1%; HSV-1: 1.6%; HSV-2: 1.0%, HSV non-typed: 0.5%). Cases due to CMV, EBV, HHV-6, MV, TOSV, HAdV, and LCMV were also detected. For meningoencephalitis, 40.7% of cases were diagnosed, HSV-1 (43.2%) and VZV (27.0%) being the most frequent agents, while cases associated with HSV-2, EV, CMV, MV, and LCMV were also detected. For encephalitis, 27.6% of cases were caused by HSV-1 (71.4%), VZV (19.1%), or EV (9.5%). Other positive neurological syndromes included cerebellitis (EV and HAdV), seizures (HSV), demyelinating disease (HSV-1 and HHV-6), myelopathy (VZV), and polyradiculoneuritis (HSV). No rabies or WNV cases were identified. EVs are the most frequent cause of meningitis, as is HSV for meningoencephalitis and encephalitis. A significant number of cases (42.9% meningitis, 59.3% meningoencephalitis, 72.4% encephalitis) still have no etiological diagnosis.

Herpes Simplex Virus-1 Encephalitis in Adults: Pathophysiology, Diagnosis, and Management

“…While HSV-2 is also capable of causing encephalitis (particularly in the immunocompromised host), HSV-1 is responsible for~90 % of HSV encephalitis in adults and children, and is the focus of this review [41]. Despite only rarely manifesting as encephalitis in infected individuals, HSV-1 is consistently the single most common cause of sporadic encephalitis worldwide [42][43][44][45][46][47][48][49][50][51][52]. The incidence of HSVE worldwide is estimated to be between 2 and 4 cases/1,000,000 [44], and the incidence in the USA is similar [53].…”

Criteria for Reducing Unnecessary Testing for Herpes Simplex Virus, Varicella-Zoster Virus, Cytomegalovirus, and Enterovirus in Cerebrospinal Fluid Samples from Adults

“…Herpes simplex virus 1 (HSV-1) is the most common treatable cause of viral encephalitis (9), while three of the most commonly identified causes of aseptic meningitis are herpes simplex virus 2 (HSV-2), varicella-zoster virus (VZV), and enteroviruses (EV) (10,11). In addition, cytomegalovirus (CMV) infections of the CNS may be of clinical concern among immunocompromised individuals (12).…”

Adenovirus Infections in Immunocompetent and Immunocompromised Patients

“…HAdVs were initially isolated mainly from military recruits with acute febrile respiratory disease and were subsequently associated with a number of clinical manifestations, including gastroenteritis, hepatitis, keratoconjunctivitis, meningoencephalitis, cystitis, upper and lower respiratory tract infections, and myocarditis, but also with noninflammatory conditions, such as obesity (14)(15)(16)(17)(18)(19)(20)(21). HAdV infections are readily transmittable and, in some instances, highly contagious.…”