Table 1 Clinical case definitions for classification of children with suspected CNS infection
Clinical and initial investigatory criteria | Microbiological & virological confirmation | |
|---|---|---|
Encephalopathy only | Altered consciousness with no evidence of typical abnormalities in imaging or CSF analysis (i.e. CSF white cell count <5/ml) | |
Encephalitis | Altered consciousness with no other cause identified & evidence of typical abnormalities in imaging or CSF analysis (i.e. CSF white cell count ≥5/ml) | Defined as ‘microbiologically/virologically confirmed' if a pathogen was identified by culture or PCR of the CSF |
Meningism only | Meningism (neck stiffness, bulging fontanelle and/or photophobia) without evidence of altered consiousness and no evidence of typical abnormalities in imaging or CSF analysis (ie white cell count <5/ml) | |
Purulent Meningitis | Febrile illness or meningism with no altered consciousness & CSF WCC >1000/ml or between 100 and 1000/ml with a predominance of polymorphonuclear cells and a CSF: plasma glucose ratio <0.5 (or unpaired CSF glucose <5 mmol) | Defined as 'microbioloigcally confirmed' if a pathogen was identified by culture or PCR of the CSF or blood |
Aseptic meningitis | Febrile illness or meningism with no altered consciousness with a normal CSF: plasma glucose ratio (>0.5) & either a CSF white cell count of 5-20/ml, or 20- 1000/ml with a lymphocyte predominance | Defined as ‘microbiologically/virologically confirmed’ if a pathogen was identified by culture or PCR of the CSF or blood |