Acute Aseptic Meningitis Syndrome

Abstract

Wallgren initially described the aseptic meningitis syndrome in 1925 as an acute community-acquired syndrome with cerebrospinal fluid (CSF) pleocytosis in the absence of a positive Gram stain and culture, without a parameningeal focus or a systemic illness and with a good clinical outcome [1]. It was not until the 1950s when advances in diagnostic virology identified seasonal patterns and a major role for viruses. Since then this clinical syndrome has been used more broadly and includes more than 100 infectious and noninfectious etiologies with some of them being treatable (see Table 4.1). The most common etiologies of aseptic meningitis in the United States (USA) are viruses such as Enterovirus, herpes simplex type 2, and West Nile virus although up to 81% of adults remain with unknown etiologies, especially when PCR testing is not routinely done [2]. Acute meningitis is defined as duration of symptoms of less than 5 days and accounts for 75% of all community-acquired meningitis cases [3]. In this chapter, we will review the diagnostic and management challenges to some of the most common causes of acute aseptic meningitis syndrome. We will briefly discuss herpes viruses, arboviruses, dengue, Zika, chikungunya, syphilis, partially treated bacterial meningitis, human immunodeficiency virus, and Lyme disease as other chapters in this book cover these etiologies extensively.