Subtypes:
(Median 8, range 5–9) | Possible symptoms:
(Median 8, range 7–9) | Supportive examination findings:
(Median 8, range 6–9) | Diagnostic criteria: All levels of diagnostic certainty for irMeningitis require a supportive history, examination, and timing relative to ICI therapy plus:
(Accuracy median 8, range 7–9; usability median 8.5, range 6–9) |
Aseptic meningitis
Note: meningoencephalitis is considered part of encephalitis | Headache (including change in chronic headache) Neck stiffness Photophobia Nausea Vomiting Lethargy (rare) May have symptoms of increased intracranial pressure: transient visual obscurations, peripheral vision loss, horizontal diplopia, pulsatile tinnitus
Note: altered mental status or seizures suggest coexisting encephalitis | Nuchal rigidity Photophobia Kernig sign (rare) Brudzinski sign (rare) May have signs of increased intracranial pressure: papilledema, vision loss, pseudo-abducens palsy Hearing loss May be febrile or afebrile
| Definite
Required:Symptoms and signs consistent with meningitis (headache/neck stiffness/photophobia without focal neurologic deficits, seizures or encephalopathy suggestive of parenchymal involvement) AND Inflammation on CSF studies (pleocytosis (>5 and/or elevated protein) AND Exclusion of infectious cause (including negative HSV PCR and negative Cryptococcal antigen), and of leptomeningeal carcinomatosis (including negative cytology and/or flow cytometry as appropriate for tumor type*) AND Stabilization or improvement with immunomodulation including steroids and/or discontinuation of checkpoint inhibitor
Supportive:
1. Leptomeningeal and/or pachymeningeal enhancement with absence of parenchymal enhancement on MRI brain with contrast* may require additional lumbar puncture(s) if high suspicion of leptomeningeal carcinomatosis |
Evaluation may include:
(Median 8, range 6–9) | Probable
Required:Symptoms and signs consistent with meningitis (headache/neck stiffness/photophobia without focal neurologic deficits, seizures or encephalopathy suggestive of parenchymal involvement) AND Inflammation on CSF studies (pleocytosis (>5 WBC) and/or elevated protein) AND Exclusion of infectious cause (including negative HSV PCR and negative Cryptococcal antigen) and of leptomeningeal carcinomatosis (including negative cytology and/or flow cytometry as appropriate for tumor type*)
Supportive:
1. Leptomeningeal and/or pachymeningeal enhancement with absence of parenchymal enhancement on MRI brain with contrast* may require additional lumbar puncture(s) if high suspicion of leptomeningeal carcinomatosis |
Common:MRI brain with contrast Lumbar puncture with CSF studies including opening pressure; cell counts and differential; total protein and glucose* measurement; oligoclonal bands* and IgG index*; cytology and/or flow cytometry**; Gram stain and culture; HSV PCR; Cryptococcal antigen; other infectious studies as appropriate*** Blood cultures
*These studies typically require corresponding serum levels for interpretation
**As appropriate for primary cancer
***Consider specific studies based on local epidemiology, seasonal incidence, travel history and other patient risk factors; a film array may incorporate testing of many infectious agents and obviate the need for separate testing |
Possible:CT head (should consider performing with contrast if unable to perform MRI brain) Additional infectious serologies based on local epidemiology, seasonal incidence, travel history and other patient risk factors
| Possible
Required:
1. Symptoms and signs consistent with meningitis (headache/neck stiffness/photophobia)
Supportive:Stabilization or improvement with immunomodulation including steroids and/or discontinuation of checkpoint inhibitor Leptomeningeal and/or pachymeningeal enhancement with absence of parenchymal enhancement on MRI brain with contrast
|
Uncommon:Meningeal biopsy CSF cytokine levels such IL-6, IL-10 Metagenomic next-generation sequencing for infectious causes
|