(Redirected from Aseptic meningitis)
Jump to: navigation, search

Illu meninges.jpg
Meninges of the central nervous system: dura mater, arachnoid, and pia mater.

Meningitis Main Page

Patient Information




Viral Meningitis
Bacterial Meningitis
Fungal Meningitis

Differential Diagnosis


For patient information click here.

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Seyedmahdi Pahlavani, M.D. [2]
Synonyms and Keywords: Leptomeningitis, Inflammation of meninges


The meninges (singular meninx) is the system of membranes which envelop the central nervous system. The meninges consist of three layers: the dura mater, the arachnoid mater, and the pia mater. The primary function of the meninges and of the cerebrospinal fluid is to protect the central nervous system. Meningitis is the inflammation of these protective membranes.
Meningitis may have been described in the Middle Ages, but it was first accurately identified by the Swiss Vieusseux (a scientific-literary association) during an outbreak in Geneva, Switzerland in 1805. In 1661, Thomas Willis first described the inflammation of meninges and an epidemic of meningitis. In the 17th century, Robert Whytt provided a detailed explanation of tuberculous meningitis and its stages. This was further elaborated by John Cheyne in the same century. Meningococcal meningitis was than described by Gaspard Vieusseux, Andre Matthey in Geneva and Elisa North in Massachussetes.
Meningitis may develop in response to a number of causes, including infectious agents (bacteria, viruses, fungi, or other organisms) or non-infectious causes, such as systemic illnesses that may involve CNS (e.g. neoplasms or connective tissue diseases, such as sarcoidosis, systemic lupus erythematosus (SLE), and wegener's) or certain drugs (e.g. nonsteroidal antiinflammatory drugs, intravenous immunoglobulin, intrathecal agents, and trimethoprim-sulfamethoxazole). While some forms of meningitis are mild and resolve spontaneously (e.g. viral meningitis), meningitis is a potentially serious condition owing to the proximity of the inflammation to the brain and spinal cord. The potential for serious neurologic damage or even death necessitates prompt medical attention and evaluation. The common presenting features of meningitis are, fever, neck stiffness and headache. Other symptoms include, photophobia (inability to tolerate bright light), phonophobia (inability to tolerate loud noises), irritability, altered mental status (in small children), and seizure. Physical examination of meningitis may vary in adults and infants. In adults, physical examination findings may include bradycardia, disorientation, papilledema, neck stiffness, positive brudzinski's and kernig's sign. However, petechial rash, bulging fontanelle, neck stiffness, jaundice, and convulsions are physical examination findings in infants. Diagnosis is based on clinical findings and CSF analysis. Treatment options are based on etiology and varies from supportive care and observing the patient (viral meningitis) to antibiotic therapy for bacterial meningitis or chemotherapy and/or irradiation for neoplastic meningitis.[1][2][3][4][5][6][4][7][8]


Etiology Common causes Less common causes
  • Arthrographis spp[18]
Spirochetal --
Protozoal and Helminthic
Noninfectious conditions


Meningitis could be classified to two main groups based on etiology:

  • Infectious
  • Non-infectious

Infectious meningitis

Infectious meningitis may be classified as the following algorithm based on chronicity of symptoms.

Infectious Meningitis

Non-infectious meningitis

Systemic illnesses, such as malignancies and connective tissue diseases (e.g. sarcoidosis, SLE, and wegener's) may involve meninges in their course and present as chronic meningitis.

Certain drugs may cause meningeal irritation and resemble as meningitis including:

Differential diagnosis

Diseases Symptoms Physical Examination Past medical history Diagnostic tests Other Findings
Headache LOC Motor weakness Abnormal sensory Motor Deficit Sensory deficit Speech difficulty Gait abnormality Cranial nerves CT /MRI CSF Findings Gold standard test
Meningitis + - - - - + + - - History of fever and malaise - Leukocytes,


↓ Glucose

CSF analysis[28] Fever, neck


Encephalitis + + +/- +/- - - + +/- + History of fever and malaise + Leukocytes, ↓ Glucose CSF PCR Fever, seizures, focal neurologic abnormalities
Brain tumor[29] + - - - + + + - + Weight loss, fatigue + Cancer cells[30] MRI Cachexia, gradual progression of symptoms
Hemorrhagic stroke + + + + + + + + - Hypertension + - CT scan without contrast[31][32] Neck stiffness
Subdural hemorrhage + + + + + - - - + Trauma, fall + Xanthochromia[33] CT scan without contrast[31][32] Confusion, dizziness, nausea, vomiting
Neurosyphilis[34][35] + - + + + + - + - STIs + Leukocytes and protein CSF VDRL-specifc

CSF FTA-Ab -sensitive[36]

Blindness, confusion, depression,

Abnormal gait

Complex or atypical migraine + - + + - - + - - Family history of migraine - - Clinical assesment Presence of aura, nausea, vomiting
Hypertensive encephalopathy + + - - - - + + - Hypertension + - Clinical assesment Delirium, cortical blindness, cerebral edema, seizure
Wernicke’s encephalopathy - + - - - + + + + History of alcohal abuse - - Clinical assesment and lab findings Ophthalmoplegia, confusion
CNS abscess + + - - + + + - - History of drug abuse, endocarditis, immunosupression + leukocytes, glucose and protien MRI is more sensitive and specific High grade fever, fatigue,nausea, vomiting
Drug toxicity - + - + + + - + - - - - Drug screen test Lithium, Sedatives, phenytoin, carbamazepine
Conversion disorder + + + + + + + + History of emotional stress - - Diagnosis of exclusion Tremors, blindness, difficulty swallowing
Metabolic disturbances (electrolyte imbalance, hypoglycemia) - + + + + + - - + - - Hypoglycemia, hypo and hypernatremia, hypo and hyperkalemia Depends on the cause Confusion, seizure, palpitations, sweating, dizziness, hypoglycemia
Multiple sclerosis exacerbation - - + + - + + + + History of relapses and remissions + CSF IgG levels

(monoclonal bands)

Clinical assesment and MRI [37] Blurry vision, urinary incontinence, fatigue
Seizure + + - - + + - - + Previous history of seizures - Mass lesion Clinical assesment and EEG [38] Confusion, apathy, irritability,


Diagnosis of meningitis, is based on clinical presentation in combination with CSF analysis. CSF analysis has major role for diagnosis and rule out other possibilities. The following table summarizes the CSF findings in different types of meningitis.[39][40][41][42][3]

Cerebrospinal fluid level Normal level Bacterial meningitis[42] Viral meningitis[42] Fungal meningitis Tuberculous meningitis[43] Neoplastic meningitis[39]
Cells/ul < 5 >300 10-1000 10-500 50-500 >4
Cells Lymphocyte Leukocyte > Lymphocyte Lymphocyte > Leukocyte Lymphocyte > Leukocyte Lymphocyte > Leukocyte Lymphocyte > Leukocyte
Total protein (mg/dl) 45-60 Typically 100-500 Normal or slightly high High Typically 100-200 >50
Glucose ratio (CSF/plasma)[40] > 0.5 < 0.3 > 0.6 <0.3 < 0.5 <0.5
Lactate (mmols/l)[41] < 2.1 > 2.1 < 2.1 >3.2 > 2.1 >2.1
Others Intra-cranial pressure (ICP) = 6-12 (cm H2O) CSF gram stain, CSF culture, CSF bacterial antigen PCR of HSV-DNA, VZV CSF gram stain, CSF india ink PCR of TB-DNA CSF tumour markers such as alpha fetoprotein, CEA


  1. Attia J, Hatala R, Cook DJ, Wong JG (1999). "The rational clinical examination. Does this adult patient have acute meningitis?". JAMA. 282 (2): 175–81. PMID 10411200. 
  2. Accessed on Jan 9th, 2017
  3. 3.0 3.1 Brouwer MC, Tunkel AR, van de Beek D (2010). "Epidemiology, diagnosis, and antimicrobial treatment of acute bacterial meningitis.". Clin Microbiol Rev. 23 (3): 467–92. PMC 2901656Freely accessible. PMID 20610819. doi:10.1128/CMR.00070-09. 
  4. 4.0 4.1 Durand ML, Calderwood SB, Weber DJ, Miller SI, Southwick FS, Caviness VS; et al. (1993). "Acute bacterial meningitis in adults. A review of 493 episodes.". N Engl J Med. 328 (1): 21–8. PMID 8416268. doi:10.1056/NEJM199301073280104. 
  5. van de Beek D, de Gans J, Spanjaard L, Weisfelt M, Reitsma JB, Vermeulen M (2004). "Clinical features and prognostic factors in adults with bacterial meningitis.". N Engl J Med. 351 (18): 1849–59. PMID 15509818. doi:10.1056/NEJMoa040845. 
  6. van de Beek D, de Gans J, Spanjaard L, Weisfelt M, Reitsma JB, Vermeulen M (2004). "Clinical features and prognostic factors in adults with bacterial meningitis". N. Engl. J. Med. 351 (18): 1849–59. PMID 15509818. doi:10.1056/NEJMoa040845. 
  7. Domingo P, Mancebo J, Blanch L, Net A, Nolla J (1988). "Fever in adult patients with acute bacterial meningitis.". J Infect Dis. 158 (2): 496. PMID 3403999. 
  8. Thomas KE, Hasbun R, Jekel J, Quagliarello VJ (2002). "The diagnostic accuracy of Kernig's sign, Brudzinski's sign, and nuchal rigidity in adults with suspected meningitis.". Clin Infect Dis. 35 (1): 46–52. PMID 12060874. doi:10.1086/340979. 
  9. Villanueva JL, Cordero E, Caballero-Granado FJ, Regordan C, Becerril B, Pachón J (1997). "Pneumocystis carinii meningoradiculitis in a patient with AIDS.". Eur J Clin Microbiol Infect Dis. 16 (12): 940–2. PMID 9495679. 
  10. Baena Luna MR, Muñoz García J, Grancha Bertolín L, Sanz García M (1998). "[Presence of Pneumocystis carinii in cerebrospinal fluid].". An Med Interna. 15 (5): 265–6. PMID 9629775. 
  11. Melo JC, Srinivasan S, Scott ML, Raff MJ (1980). "Cryptococcus albidus meningitis.". J Infect. 2 (1): 79–82. PMID 7185917. 
  12. OHASHI Y (1960). "On a rare disease due to Alternaria tenuis Nees (alternariasis).". Tohoku J Exp Med. 72: 78–82. PMID 13730495. 
  13. Shinde RS, Mantur BG, Patil G, Parande MV, Parande AM (2008). "Meningitis due to Rhodotorula glutinis in an HIV infected patient.". Indian J Med Microbiol. 26 (4): 375–7. PMID 18974495. 
  14. Fincher RM, Fisher JF, Lovell RD, Newman CL, Espinel-Ingroff A, Shadomy HJ (1991). "Infection due to the fungus Acremonium (cephalosporium).". Medicine (Baltimore). 70 (6): 398–409. PMID 1956281. 
  15. Fuste FJ, Ajello L, Threlkeld R, Henry JE (1973). "Drechslera hawaiiensis: causative agent of a fatal fungal meningo-encephalitis.". Sabouraudia. 11 (1): 59–63. PMID 4739938. 
  16. Rosales CM, Jackson MA, Zwick D (2004). "Malassezia furfur meningitis associated with total parenteral nutrition subdural effusion.". Pediatr Dev Pathol. 7 (1): 86–90. PMID 15255040. doi:10.1007/s10024-003-4030-5. 
  17. Symoens F, Knoop C, Schrooyen M, Denis O, Estenne M, Nolard N; et al. (2006). "Disseminated Scedosporium apiospermum infection in a cystic fibrosis patient after double-lung transplantation.". J Heart Lung Transplant. 25 (5): 603–7. PMID 16678041. doi:10.1016/j.healun.2005.12.011. 
  18. Chin-Hong PV, Sutton DA, Roemer M, Jacobson MA, Aberg JA (2001). "Invasive fungal sinusitis and meningitis due to Arthrographis kalrae in a patient with AIDS.". J Clin Microbiol. 39 (2): 804–7. PMC 87827Freely accessible. PMID 11158158. doi:10.1128/JCM.39.2.804-807.2001. 
  19. Girmenia C, Micozzi A, Venditti M, Meloni G, Iori AP, Bastianello S; et al. (1991). "Fluconazole treatment of Blastoschizomyces capitatus meningitis in an allogeneic bone marrow recipient.". Eur J Clin Microbiol Infect Dis. 10 (9): 752–6. PMID 1810730. 
  20. Naficy AB, Murray HW (1990). "Isolated meningitis caused by Blastoschizomyces capitatus.". J Infect Dis. 161 (5): 1041–2. PMID 2324536. 
  21. Kantarcioğlu AS, Hatemi G, Yücel A, De Hoog GS, Mandel NM (2003). "Paecilomyces variotii central nervous system infection in a patient with cancer.". Mycoses. 46 (1-2): 45–50. PMID 12588483. 
  22. Fagerburg R, Suh B, Buckley HR, Lorber B, Karian J (1981). "Cerebrospinal fluid shunt colonization and obstruction by Paecilomyces variotii. Case report.". J Neurosurg. 54 (2): 257–60. PMID 7192726. doi:10.3171/jns.1981.54.2.0257. 
  23. Kutleša M, Mlinarić-Missoni E, Hatvani L, Voncina D, Simon S, Lepur D; et al. (2012). "Chronic fungal meningitis caused by Aureobasidium proteae.". Diagn Microbiol Infect Dis. 73 (3): 271–2. PMID 22504065. doi:10.1016/j.diagmicrobio.2012.03.007. 
  24. Krcmery V, Mateicka F, Grausova S, Kunova A, Hanzen J (1999). "Invasive infections due to Clavispora lusitaniae.". FEMS Immunol Med Microbiol. 23 (1): 75–8. PMID 10030550. 
  25. MOORE M, RUSSELL WO, SACHS E (1946). "Chronic leptomeningitis and ependymitis caused by Ustilago, probably U. zeae (corn smut).". Am J Pathol. 22: 761–77. PMID 20991975. 
  26. Centers for Disease Control and Prevention (CDC) (2002). "Exophiala infection from contaminated injectable steroids prepared by a compounding pharmacy--United States, July-November 2002.". MMWR Morb Mortal Wkly Rep. 51 (49): 1109–12. PMID 12530707. 
  27. Pettit AC, Pugh ME (2013). "Index case for the fungal meningitis outbreak, United States.". N Engl J Med. 368 (10): 970. PMID 23465119. doi:10.1056/NEJMc1300630. 
  28. Carbonnelle E (2009). "[Laboratory diagnosis of bacterial meningitis: usefulness of various tests for the determination of the etiological agent].". Med Mal Infect. 39 (7-8): 581–605. PMID 19398286. doi:10.1016/j.medmal.2009.02.017. 
  29. Morgenstern LB, Frankowski RF (1999). "Brain tumor masquerading as stroke.". J Neurooncol. 44 (1): 47–52. PMID 10582668. 
  30. Weston CL, Glantz MJ, Connor JR (2011). "Detection of cancer cells in the cerebrospinal fluid: current methods and future directions.". Fluids Barriers CNS. 8 (1): 14. PMC 3059292Freely accessible. PMID 21371327. doi:10.1186/2045-8118-8-14. 
  31. 31.0 31.1 Birenbaum D, Bancroft LW, Felsberg GJ (2011). "Imaging in acute stroke.". West J Emerg Med. 12 (1): 67–76. PMC 3088377Freely accessible. PMID 21694755. 
  32. 32.0 32.1 DeLaPaz RL, Wippold FJ, Cornelius RS, Amin-Hanjani S, Angtuaco EJ, Broderick DF; et al. (2011). "ACR Appropriateness Criteria® on cerebrovascular disease.". J Am Coll Radiol. 8 (8): 532–8. PMID 21807345. doi:10.1016/j.jacr.2011.05.010. 
  33. Lee MC, Heaney LM, Jacobson RL, Klassen AC (1975). "Cerebrospinal fluid in cerebral hemorrhage and infarction.". Stroke. 6 (6): 638–41. PMID 1198628. 
  34. Liu LL, Zheng WH, Tong ML, Liu GL, Zhang HL, Fu ZG; et al. (2012). "Ischemic stroke as a primary symptom of neurosyphilis among HIV-negative emergency patients.". J Neurol Sci. 317 (1-2): 35–9. PMID 22482824. doi:10.1016/j.jns.2012.03.003. 
  35. Berger JR, Dean D (2014). "Neurosyphilis". Handb Clin Neurol. 121: 1461–72. PMID 24365430. doi:10.1016/B978-0-7020-4088-7.00098-5. 
  36. Ho EL, Marra CM (2012). "Treponemal tests for neurosyphilis--less accurate than what we thought?". Sex Transm Dis. 39 (4): 298–9. PMC 3746559Freely accessible. PMID 22421697. doi:10.1097/OLQ.0b013e31824ee574. 
  37. Giang DW, Grow VM, Mooney C, Mushlin AI, Goodman AD, Mattson DH; et al. (1994). "Clinical diagnosis of multiple sclerosis. The impact of magnetic resonance imaging and ancillary testing. Rochester-Toronto Magnetic Resonance Study Group.". Arch Neurol. 51 (1): 61–6. PMID 8274111. 
  38. Manford M (2001). "Assessment and investigation of possible epileptic seizures.". J Neurol Neurosurg Psychiatry. 70 Suppl 2: II3–8. PMC 1765557Freely accessible. PMID 11385043. 
  39. 39.0 39.1 Le Rhun E, Taillibert S, Chamberlain MC (2013). "Carcinomatous meningitis: Leptomeningeal metastases in solid tumors.". Surg Neurol Int. 4 (Suppl 4): S265–88. PMC 3656567Freely accessible. PMID 23717798. doi:10.4103/2152-7806.111304. 
  40. 40.0 40.1 Chow E, Troy SB (2014). "The differential diagnosis of hypoglycorrhachia in adult patients.". Am J Med Sci. 348 (3): 186–90. PMC 4065645Freely accessible. PMID 24326618. doi:10.1097/MAJ.0000000000000217. 
  41. 41.0 41.1 Leen WG, Willemsen MA, Wevers RA, Verbeek MM (2012). "Cerebrospinal fluid glucose and lactate: age-specific reference values and implications for clinical practice.". PLoS One. 7 (8): e42745. PMC 3412827Freely accessible. PMID 22880096. doi:10.1371/journal.pone.0042745. 
  42. 42.0 42.1 42.2 Negrini B, Kelleher KJ, Wald ER (2000). "Cerebrospinal fluid findings in aseptic versus bacterial meningitis.". Pediatrics. 105 (2): 316–9. PMID 10654948. 
  43. Caudie C, Tholance Y, Quadrio I, Peysson S (2010). "[Contribution of CSF analysis to diagnosis and follow-up of tuberculous meningitis].". Ann Biol Clin (Paris). 68 (1): 107–11. PMID 20146981. doi:10.1684/abc.2010.0407. 

af:Meningitis cs:Meningitida da:Meningitis de:Meningitis eo:Meningito eu:Meningitis fa:مننژیت gl:Meninxite ko:수막염 hr:Meningitis id:Meningitis is:Heilahimnubólga it:Meningite he:דלקת קרום המוח kk:Миқұрт la:Meningitis lt:Meningitas hu:Agyhártyagyulladás ms:Meningitis nl:Hersenvliesontsteking no:Meningitt qu:Ñutqu p'istuq llika unquy sq:Meningjiti simple:Meningitis sl:Meningitis fi:Aivokalvontulehdus sv:Hjärnhinneinflammation