Meningitis resident survival guide

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Niloofarsadaat Eshaghhosseiny, MD[2]

Overview

Meningitis is characterized by inflammation of the leptomeninges.Meningitis causes are divided to infectious and non-infectious process.Infectious causes are included,bacterial,viral,fungal,protozoal and,treponemal. 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).The classic triad of meningitis is headache,neck stiffness and fever.

Causes

Life Threatening Causes

Life-threatening causes include conditions that may result in death or permanent disability within 24 hours if left untreated.

• Bacterial
• Viral
• Fungal

Common Causes

Bacterial:

• Streptococcus pneumoniae
• Neisseria meningitis
• Hemophilus influenza
• Group B streptococcus
• Listeria monocytogenes

Viral:

• Enteroviruses
• Herpes simplex viruses 1 and 2
• Arboviruses

Fungal:

• Cryptococcus neoformans
• Aspergillus sp.
• Blastomyces dermatitidis
• Coccidioides immitis
• Candida spp.
• Histoplasma capsulatum
• Sporothrix schencki

Diagnosis

Adapted from IDSA guidline

suspicion for bacterial meningitis

yes

Immuncompromised,new onset seizure,History of CNS dis,altered consciousness,papilledema,focal neuorologic deficit,delay in performance of diagnostic of LP

Yes

No

Blood culture stat,CTscan

Blood culture and LP stat

Negative CTscan

LP

• Cerebrospinal Fluid Analysis:

Cerebrospinal fluid level	Normal level	Bacterial meningitis	Viral meningitis (except SARS-CoV-2 meningitis)	SARS-CoV-2 associated meningitis	Fungal meningitis	Tuberculous meningitis	Neoplastic meningitis
Cells/ul	< 5	>300	10-1000	10-1000	10-500	50-500	>4
Cells	Lymphocyte	Leukocyte > Lymphocyte	Lymphocyte > Leukocyte	Lymphocyte > Neutrophil	Lymphocyte > Leukocyte	Lymphocyte > Leukocyte	Lymphocyte > Leukocyte
Total protein (mg/dl)	45-60	Typically 100-500	Normal or slightly high	Normal or slightly high	High	Typically 100-200	>50
Glucose ratio (CSF/plasma)	> 0.5	< 0.3	> 0.6	> 0.6	<0.3	< 0.5	<0.5
Lactate (mmols/l)	< 2.1	> 2.1	< 2.1	NA	>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	RT-PCR for detection of viral RNA i n CSF ( not approved by FDA)	CSF gram stain, CSF india ink	PCR of TB-DNA	CSF tumour markers such as alpha fetoprotein, CEA

Treatment

Adapted from IDSA guidline

suspicion for bacterial meningitis

yes

Immuncompromised,new onset seizure,History of CNS dis,altered consciousness,papilledema,focal neuorologic deficit,delay in performance of diagnostic of LP

Yes

No

Blood culture stat

Blood culture and LP stat

Dexamethasone and empirical antibiotic therapy

Dexamethasone and empirical antibiotic therapy

Negative CTscan of head

Positive CT scan

Csf findings c/w bacterial meningitis

Perform LP

Continue therapy or consider alternative diagnosis

Yes

Continue therapy

Do's

• Administration of empiric antibiotic to suspicious patients immediately after the performance of lumbar puncture or/and blood cultures sampling.

Don'ts

• Do not delay the delivery of empiric antibiotic for clinical investigation.