Review ArticleBacterial Meningitis in the Absence of Pleocytosis in Children A Systematic ReviewZimmermann, Petra MD, PhD*,†,‡,§; Curtis, Nigel FRCPCH, PhD‡,§,¶Author Information From the *Department of Paediatrics, Fribourg Hospital HFR †Faculty of Science and Medicine, University of Fribourg, Fribourg, Switzerland ‡Department of Paediatrics, The University of Melbourne §Infectious Diseases Research Group, Murdoch Children’s Research Institute ¶Infectious Diseases Unit, The Royal Children’s Hospital Melbourne, Parkville, Australia. Accepted for publication January 10, 2021 The authors have no funding or conflicts of interest to disclose. P.Z. drafted the initial article. N.C. critically revised the article and both authors approved the final article as submitted. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.pidj.com). Address for correspondence: Petra Zimmermann, MD, PhD, Faculty of Science and Medicine, University of Fribourg, Route des Arsenaux 41, 1700 Fribourg, Switzerland. E-mail: [email protected]. The Pediatric Infectious Disease Journal: June 2021 - Volume 40 - Issue 6 - p 582-587 doi: 10.1097/INF.0000000000003085 Buy SDC Metrics Abstract One of the main features of bacterial meningitis is pleocytosis. However, when children with meningitis present within hours of onset of symptoms, there is the possibility that the meninges are not yet sufficiently inflamed to lead to a raised cerebrospinal fluid (CSF) white blood cell count. A systematic search was done to identify published studies reporting children with culture- or polymerase chain reaction-proven bacterial meningitis in the absence of pleocytosis. We identified 26 studies describing 62 children (18 neonates). In those in whom fever duration was specified, 32 (80%) of 40 had a fever for less than or equal to 24 hours before lumbar puncture (LP). In those in whom the glucose level was reported, it was normal in 14 (82%) of 17 neonates and 33 (80%) of 41 older infants and children. The protein level was normal in 8 (44%) of 17 neonates and 32 (80%) of 40 older infants and children. Twelve of the 62 children had a Gram stain of their CSF and this was positive in 2 (17%). Simultaneous blood cultures were positive in 5 (28%) of 18 neonates and 21 (68%) of 31 older infants and children. There was no association between the absence of pleocytosis and particular bacteria. All of the 10 children who had a second LP had an abnormal CSF including pleocytosis. These findings indicate that the absence of pleocytosis does not exclude bacterial meningitis reliably and should be interpreted in the context of the duration of illness. CSF samples, particularly those from cases with relatively short symptom duration, should be cultured even when the cell count and biochemistry are normal. A second LP can be helpful when bacterial meningitis is suspected despite a normal initial CSF. Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.