CNS infections + Hydrocephalus Flashcards
Investigations for ?meningitis
FBC, CRP, U+E, LFTs
Coagulation screen
Blood culture, glucose + gas
Lumbar puncture
Organisms causing meningitis
Meningitides = kids
Strep pneu
Haem influenza = neonatal
Management of meningitis
Dex
IV cefotaxime (empirical) + amoxicillin if <3mths or >50 y/o
Cloramphenicol if allergic
Rifampicin/ ciprofloxacin for family
Pathology of encephalitis
Acute inflammatory brain disease due to immune response
Inflammation of brain parenchyma
Causes of encephalitis
Viral (HSV, Polio, VZV, EBV, HIV)
Bacterial - listeria, syphilis
Autoimmune, NMDA receptor encepalitis
RF for encephalitis
Immunosuppression
Travel to low-income nations
Complications of encephalitis
Seizures
SIADH
Increased ICP
Coma
S+S of encephalitis
Fever, chills, malaise
Meningism (nuchal rigidity)
Parenchymal involvement - seizures, altered mental state
Investigations + results for ?encephalitis
Blood + CSF cultures
Serology
Tissue analysis (Tzanck smear)
Brain biopsy (definitive)
Complications of meningitis
Cerebral oedema Cerebral herniation Deafness Epilepsy Hydrocephalus Cognitive deficits
Changes in CSF for bacterial meningitis
Appears cloudy Increased pressure Neutrophils present High protein Low glucose Gram stain, culture for microbiology
Changes in CSF for viral meningitis
Appears clear Normal pressure Lymphocytes present High protein Normal glucose PCR assay for microbiology
Changes in CSF for fungal meningitis
Appears cloudy Normal pressure Mononuclear cells present Low glucose Acid fast bacillus stain, PCR for micro
Changes in CSF for TB meningitis
Appears opaque Increased pressure Neutrophils present High protein Low glucose Acid fast bacillus stain, PCR for microbiology
Changes in CSF for cryptococcal meningitis
Appears clear Increased pressure Lymphocutes present Low glucose India ink stain for microbiology
Pathology of normal pressure hydrocephalus
Enlarged ventricular size with normal opening pressures
What is the triad of symptoms associated with normal pressure hydrocephalus?
Cognitive impairement, gait disturbance, urinary incontinence
What is the common causes of secondary normal pressure hydrocephalus?
SAH + meningitis
What investigations are used in normal pressure hydrocephalus?
MRI
Lumbar puncture
Management of normal pressure hydrocephalus
Shunt
S+S of raised ICP
CN V6 palsies
Papilloedema
Periorbital bruising
Bradycardia, resp depression + HTB (Cushings triad)
What is Kernohans notch phenomenon?
Combinations of conrtalateral pupillary dilatation + ipsilateral weakness
