Meningitis

Inflammation of the meninges

Causes Infectious- Bacteria- S.pneumoniae, N.meningitidis, H.influenzae;

L.monocytogenes in neonates & elderly; S.aureus & Gram –ve bacteria- post-traumatic/post-procedure; TBM- mostly chronic, may present acutely

Aseptic- partially treated bacterial meningitis, syphilis, malaria, fungal, amoebic-N.fowleri

Virus- enterovirus, HSV, VZV, mumps, HIV Non-infectious- metastatic cancer, sarcoid, SLE,

vasculitis, drugs-NSAIDs, Abx, IVIG

Presentation Acute- Fever, headache, nuchal rigidity, altered sensorium Irritability, phono/photophobia Petechial rash in meningococcal meningitis Kernig sign- passive extension of knee, with flexed hip & knee Brudzinski sign- flexion of neck causes flexion of hip & knee Complications- Sepsis, DIC, Waterhouse-Friderichsen syndrome Raised ICP, hydrocephalus Seizures Residual impaired vision/hearing & cognitive impairment

Investigation Blood tests- CBC, blood culture, Na, Cr, SGPT CSF examination- pressure & appearance Glucose-low, protein-high; normal in viral meningitis Cells- RBC, WBC, malignant WBC- PMN-bacterial, mononuclear-others Gram stain, culture, Z-N stain, India ink stain Serology CT scan- Urgent- before LP- papilledema, focal seizures/signs Elective- after LP- to look for complications

Treatment Antibiotics- empiric, ASAP, x10-14 days 3rd generation cephalosporin + vancomycin, for suspected S.aureus +Ampicillin, for L.monocytogenes Steroids- Dexamethasone, first dose before Abx; x4 days

specially S.p in adults & H.i in children Supportive- ABC IV fluids, mechanical ventilation Raised ICP- mannitol; hydrocephalus- VP shunt Seizures- AEDs x1 year,

if no recurrence/structural brain damage

Brain abscess Intracerebral pus collection Usually mixed bacterial infection Due to- Direct extension of cranial infections Penetrating head injury/surgery Infected emboli s/s- due to raised ICP/mass effect Dx- CT scan/MRI, with contrast Rx- surgical drainage + antibiotics ± AEDs

Brain abscess Intracerebral pus collection Usually mixed bacterial infection Due to- Direct extension of cranial infections Penetrating head injury/surgery Infected emboli s/s- due to raised ICP/mass effect Dx- CT scan/MRI, with contrast Rx- surgical drainage + antibiotics ± AEDs