Clinical Background
Meningitis is an inflammation of the meninges that may be caused by many different etiologic agents.
Epidemiology
- Incidence
- Bacterial - 4-6/100,000
- Transmission
- Hematogenous dissemination (bacteremia, viremia)
- Trauma - surgery, head trauma (basilar skull fracture)
Classification
- Viral - most common cause of meningitis
- Enterovirus
- Herpes simplex virus
- West Nile virus
- Other arboviruses
- Mumps virus
- Lymphocytic choriomeningitis virus
- Others - Epstein-Barr virus, human immunodeficiency virus
- Bacterial
- Neisseria meningitidis
- Streptococcus pneumoniae
- Haemophilus influenzae
- Listeria monocytogenes
- E. coli
- Beta-hemolytic Group B streptococcus
- Mycobacterial
- Mycobacterium tuberculosis
- Fungal
- Blastomyces dermatitides
- Cryptococcus neoformans
- Histoplasma capsulatum
- Coccidioides immitis
- Parasites
- Amoeba - Naegleria, Acanthamoeba
- Angiostrongylus cantonensis
Clinical Presentation
- Headache
- Fever
- Meningismus, altered sensorium, seizures
- Nausea, emesis
- Focal neurologic findings
- Complications
- Shock
- Disseminated intravascular coagulation
- Focal permanent neurologic deficits
- Deafness
- Hydrocephalus
Prevention
- Viral
- Mumps vaccination
- Bacterial
- H. influenzae vaccination
- N. meningiditis vaccination in teen years
- Chemoprophylaxis for close contacts of patients with N. meningitidis
See Also
Diagnosis
Diagnosis
- Cerebrospinal fluid examination
- Bacteria culture
- Fungal culture (when clinically indicated) requires HIGH VOLUME tap
- Blood cultures
- Antigen-antibody testing, when appropriate (eg, pneumococcal antigen, dimorphic fungi serology, cryptococcal antigen)
- Viral culture from CSF not indicated (perform nucleic-acid amplification testing)
- AFB culture requires HIGH VOLUME tap
- Mycobacterium TB Amplified Detection (MTD) from CSF
- Note: MTD is less sensitive than culture
| Tests |
Tests generally appear in the order most useful for common clinical situations
| Test name: Mycobacterium tuberculosis Amplified Detection , CSF |
| ARUP #: 0060063 |
| Methodology: Transcription Mediated Amplification (Gen-Probe®) |
| Use: Identify TB as an etiological agent of meningitis |
| Limitations: AFB culture should always be ordered with this test Low level false-positive results can occur in specimens with high concentration of Mycobacteria other than M. tuberculosis A negative result does not exclude M. tuberculosis infection |
| Test name: Glucose, CSF |
| ARUP #: 0020515 |
| Methodology: Enzymatic |
| Use: Aids in differentiating bacterial from viral meningitis |
| Test name: Protein, Total, CSF |
| ARUP #: 0020514 |
| Methodology: Reflectance Spectrophotometry |
| Use: Aids in identification of meningitis |
| Test name: Cell Count, CSF |
| ARUP #: 0095018 |
| Methodology: Cell Count/Differential |
| Use: Aids in differentiating bacterial from viral meningitis |
| Test name: CSF Bacterial Culture (Includes Gram Stain 0060101) |
| ARUP #: 0060106 |
| Methodology: Standard reference procedures for bacterial stain, aerobic culture, and identification |
| Use: Identification of the organism that is the cause of meningitis |
| Test name: Blood Culture |
| ARUP #: 0060102 |
| Methodology: Bactec® 9240, continuous monitoring system. Standard reference procedures for identification of aerobic and anaerobic microorganisms |
| Use: Identification of the organism that is the cause of meningitis |
| Test name: West Nile Virus Antibodies, IgG & IgM by ELISA, CSF |
| ARUP #: 0050228 |
| Methodology: Enzyme-Linked Immunosorbent Assay |
| Use: Identify West Nile Virus as an etiological agent of meningitis |
| Test name: Arbovirus Antibodies, IgM by IFA, CSF |
| ARUP #: 0098852 |
| Methodology: Indirect Fluorescent Antibody |
| Use: Identify arbovirus as an etiological agent of meningitis |
| Test name: Lymphocytic Choriomeningitis (LCM) Antibody by CF, CSF (INACTIVE as of 11.24.08. No referral) |
| ARUP #: 0054450 |
| Methodology: Complement Fixation |
| Use: Identify LCM as an etiological agent of meningitis |
| Test name: Enterovirus Detection by RT-PCR |
| ARUP #: 0050249 |
| Methodology: Reverse Transcription/Polymerase Chain Reaction |
| Use: Identify enterovirus as an etiological agent of meningitis |
| Limitations: A negative result does not rule out the presence of PCR inhibitors in the patient specimen or Enterovirus nucleic acid in concentrations below the level of detection of the assay |
| Test name: Herpes Simplex Virus by PCR |
| ARUP #: 0060041 |
| Methodology: Polymerase Chain Reaction |
| Use: Identify herpes simplex virus as an etiological agent of meningitis |
| Limitations: A negative result does not rule out the presence of PCR inhibitors in the patient specimen or herpes simplex virus DNA concentrations below the level of detection of the assay |
| Test name: Epstein-Barr Virus by PCR |
| ARUP #: 0050246 |
| Methodology: Polymerase Chain Reaction |
| Use: Identify Epstein-Barr Virus as an etiological agent of meningitis |
| Limitations: A negative result does not rule out the presence of PCR inhibitors in the patient specimen or Epstein-Barr virus DNA in concentrations below the level of detection of the assay |
| Test name: Fungal Culture |
| ARUP #: 0060149 |
| Methodology: Standard reference procedures for fungal culture and identification of mould/yeast. DNA probes available for Histoplasma, Coccidioides, and Blastomyces |
| Use: Aids in differentiating bacterial from viral meningitis |
| Test name: Cryptococcus Antigen, CSF |
| ARUP #: 0050195 |
| Methodology: Enzyme Immunoassay |
| Use: Identify cryptococcus as an etiological agent of meningitis |
| Limitations: A negative result does not exclude the possibility of cryptococcal infection |
| Test name: Coccidioides Antibodies Panel, CSF by CF, ID, ELISA |
| ARUP #: 0050710 |
| Methodology: Complement Fixation/Immunodiffusion/Enzyme-Linked Immunosorbent Assay |
| Use: Detect both IgG and IgM antibodies in acute and convalescent samples Confirm coccidioidal disease as an etiological agent of meningitis |
| Limitations: |
| Follow-up: For equivocal results, repeat of testing in 10-14 days may be helpful |
| Test name: Histoplasma Antigen, Serum |
| ARUP #: 0092522 |
| Methodology: Enzyme Immunoassay |
| Use: Diagnose and monitor response to therapy in Histoplasma-caused disease |
| Limitations: Rarely positive in chronic cases |
| Test name: Blastomyces Antibodies by CF & ID |
| ARUP #: 0050626 |
| Methodology: Complement Fixation/Immunodiffusion |
| Use: Identify Blastomyces as an etiological agent of meningitis |
| Test name: Streptococcus pneumoniae Antigen, CSF |
| ARUP #: 0061162 |
| Methodology: Immunochromatographic Assay |
| Use: Identify streptococcus pneumoniae as an etiological agent of meningitis |
| Limitations: False-positives may occur because of cross-reactivity with other members of S. mitis group. Clinical correlation is recommended. Patients who have received the S. pneumoniae vaccines may test positive in the 48 hours following vaccination. It is recommended to avoid testing within five days of receiving vaccination. Samples from patients taking antibiotics for more than 24 hours may cause a false-negative result |
| Test name: Acanthamoeba Culture |
| ARUP #: 0060245 |
| Methodology: Culture/Microscopic Identification |
| Use: Identify Acanthamoeba as an etiological agent of meningitis |
| Limitations: This stain will detect Naegleria sp and other free-living amoeba |
| Test name: |
| ARUP #: |
| Methodology: |
| Use: Identify presence of Naegleria and Aacanthamoeba CSF specimen |
| Limitations: |
| Test name: AFB Culture (Includes AFB Stain 0060151) with Reflex to Mycobacterium tuberculosis Amplified Direct Detection (0060095) |
| ARUP #: 0060738 |
| Methodology: Standard reference procedures for stain and culture. Identification of AFB is ordered and billed separately. DNA probes are available for M. tuberculosis complex and M. avium-intracellulare complex as indicated. DNA sequencing and other molecular techniques are used for identification of other mycobacteria species. For drug susceptibilities, refer to Antimicrobial Susceptibility - AFB Mycobacteria (0060217). For AFB stain positive respiratory specimens, Mycobacterium tuberculosis Amplified Direct Detection (0060095) will be added at an additional charge. |
| Use: Identify the tuberculosis organism as an etiological agent of meningitis |
Additional Tests Available
| Test name: AFB Stain Only |
| ARUP #: 0060151 |
| Methodology: Auramine O Stain |
| Comments: |
| Test name: AFB Culture (Includes AFB Stain 0060151) |
| ARUP #: 0060152 |
| Methodology: Standard reference procedures for stain and culture. Identification of AFB is ordered and billed separately. DNA probes are available for M. tuberculosis complex and M. avium-intracellulare complex as indicated. DNA sequencing and other molecular techniques are used for identification of other mycobacteria species. For drug susceptibilities, refer to Antimicrobial Susceptibility - AFB Mycobacteria (0060217). |
| Comments: |
| Test name: Blastomyces dermatitidis Identification by DNA Probe |
| ARUP #: 0062224 |
| Methodology: Nucleic Acid Probe |
| Comments: |
| Test name: Blastomyces Antibody by CF |
| ARUP #: 0050130 |
| Methodology: Complement Fixation |
| Comments: |
| Test name: Blastomyces Antibody by ID |
| ARUP #: 0050172 |
| Methodology: Immunodiffusion |
| Comments: |
| Test name: Coccidioides immitis Identification by DNA Probe |
| ARUP #: 0062225 |
| Methodology: Nucleic Acid Probe |
| Comments: |
| Test name: Coccidioides Antibodies Panel, Serum by CF, ID, ELISA |
| ARUP #: 0050588 |
| Methodology: Complement Fixation/Immunodiffusion/Enzyme-Linked Immunosorbent Assay |
| Comments: |
| Test name: Coccidioides Antibody by CF |
| ARUP #: 0050170 |
| Methodology: Complement Fixation |
| Comments: Least sensitive in pulmonary cavitary disease |
| Test name: Coccidioides Antibody by ID |
| ARUP #: 0050183 |
| Methodology: Immunodiffusion |
| Comments: |
| Test name: Coccidioides Antibody, IgG by ELISA |
| ARUP #: 0050179 |
| Methodology: Enzyme-Linked Immunosorbent Assay |
| Comments: |
| Test name: Coccidioides Antibody, IgM by ELISA |
| ARUP #: 0050178 |
| Methodology: Enzyme-Linked Immunosorbent Assay |
| Comments: |
| Test name: Cryptococcus Antigen, Serum |
| ARUP #: 0050196 |
| Methodology: Enzyme Immunoassay |
| Comments: Serum |
| Test name: Histoplasma Antigen by EIA, Urine |
| ARUP #: 0060730 |
| Methodology: Enzyme Immunoassay |
| Comments: |
| Test name: Histoplasma capsulatum Identification by DNA Probe |
| ARUP #: 0062226 |
| Methodology: Nucleic Acid Probe |
| Comments: |
| Test name: Histoplasma Blood Culture |
| ARUP #: 0060145 |
| Methodology: Lysis Centrifugation (Isolator™)/DNA probes available for identification |
| Comments: |
| Test name: Histoplasma Antibodies by CF & ID |
| ARUP #: 0050627 |
| Methodology: Complement Fixation/Immunodiffusion |
| Comments: |
| Test name: Histoplasma Antibody by ID |
| ARUP #: 0050174 |
| Methodology: Immunodiffusion |
| Comments: |
| Test name: Meningoencephalitis Panel, CSF with Reflex to HSV Type 1 & Type 2 Glycoprotein G-Specific Ab, IgG |
| ARUP #: 0050078 |
| Methodology: Refer to individual components |
| Comments: |
References
General References
References from the ARUP Institute for Clinical and Experimental Pathology Research®
Medical Reviewers
Lehman, Christopher M., M.D. Co-Medical Director, University Hospital Clinical Laboratory; Associate Professor, Clinical Pathology, University of Utah
Petti, Cathy A., M.D. Medical Director, Infectious Diseases at ARUP Laboratories; Assistant Professor, Pathology and Medicine, University of Utah
Roberts, William L. , M.D., Ph.D. Medical Director, Automated Core Laboratory at ARUP Laboratories; Professor, Pathology, University of Utah
Comprehensive Review: March 2008
Last Update: March 2008
