Encephalitis Differential Diagnoses
- Author: David S Howes, MD; Chief Editor: Barry E Brenner, MD, PhD, FACEP more...
See the following for more information:
Other conditions to be considered include the following:
- Acute central nervous system (CNS) events, such as hemorrhagic stroke
- Acute confusional states secondary to drugs, toxins, psychosis
- Amoeba (Naegleria, Acanthamoeba)
- Head trauma
- CNS syphilis
- Intracranial hemorrhage
- Intracranial tumor
- CNS trauma
Leptospirosis in Humans
Pediatrics, Meningitis and Encephalitis
Tick-Borne Diseases, Lyme
[Guideline] Tunkel AR, Glaser CA, Bloch KC, Sejvar JJ, Marra CM, Roos KL, et al. The management of encephalitis: clinical practice guidelines by the Infectious Diseases Society of America. Clin Infect Dis. 2008 Aug 1. 47(3):303-27. [Medline].
Final 2008 West Nile Virus Activity in the United States. Centers for Disease Control and Prevention. Available at http://bit.ly/fATcE1. Accessed: April 26, 2009.
MacDonald RD, Krym VF. West Nile virus. Primer for family physicians. Can Fam Physician. 2005 Jun. 51:833-7. [Medline].
Yao K, Honarmand S, Espinosa A, Akhyani N, Glaser C, Jacobson S. Detection of human herpesvirus-6 in cerebrospinal fluid of patients with encephalitis. Ann Neurol. 2009 Mar. 65(3):257-67. [Medline].
Bloch KC, Glaser C. Diagnostic approaches for patients with suspected encephalitis. Curr Infect Dis Rep. 2007 Jul. 9(4):315-22. [Medline].
Hayasaka D, Aoki K, Morita K. Development of simple and rapid assay to detect viral RNA of tick-borne encephalitis virus by reverse transcription-loop-mediated isothermal amplification. Virol J. 2013 Mar 4. 10(1):68. [Medline].
|CSF Finding (Normal)||Bacterial Meningitis||Viral Meningitis*||Fungal Meningitis|
|Pressure (5-15 cm water)|
|Cell counts, mononuclear cells/µL|
6 mo+ (0-5)
Euglycemia (>50% serum)
Hyperglycemia (>30% serum)
Preterm (65-150 mg/dL)
Term (20-170 mg/dL
6 mo+ (15-45 mg/dL)
|*Some bacteria (eg, Mycoplasma, Listeria, Leptospira, Borrelia burgdorferi [Lyme disease]) cause alterations in spinal fluid that resemble the viral profile. An aseptic profile is also typical of partially treated bacterial infections (>33%, especially those in children, are treated with antimicrobials) and of the 2 most common causes of encephalitis—the arboviruses and the potentially curable HSV.|
† Wait 4 hours after glucose load.
AFB—acid-fast bacillus; CSF—cerebrospinal fluid; EEE-eastern equine encephalitis; HSV—herpes simplex virus; RBC—red blood cell; TB—tuberculosis; WBC—white blood cell.