CNS infections Flashcards
meningitis def
Inflammation of the arachnoid and pia mater in addition to the interposed CSF in the subarachnoid space
Extends throughout the subarachnoid space around the brain, spinal cord, and ventricles
med. emergency
clinical manifestations
ha, fever, menigismus + AMS
elderly may only present with lethargy, consider LP
insidious onset of symps >1 - several days
acute fulminant over sev. hrs -petechia over whole body
+ meningitis signs
Kernig
Brudzinski
CSF abnormalities
see slide 5
meningitis levels
bac: >1000 cells, PMNs, low glucose
presentation
neck pain, photophobia \+ Kernig's, Brudzinski's -faint rash on lower legs -close eyes, speech slurred: inc. CSF, inc. pressure on brain, at risk for herniation *get CT before LP
-what to do next?
CT first, LP, blood Cx (i.e. pneumococcus meningitis)
abx?
ceftriaxone: high dose to penetrate CSF
+ vancomycin: empirical, slightly resistant org.
if suspect viral meningitis: tx
ADD acyclovir IV
meningococcal meningitis
Purulent CSF with G- IC and EC diplococci
Petechial or non-blanchable purpuric rash
*Terminal complement deficiency (C5-C9), @ risk for encap. org infections (gon, streph inf) asplenia, predispose patients to infection
Waterhouse - Friderichsen Syndrome: overwhelming sepsis–>intravasc. collapse-DIC
Kernig
lift knee up
+ if pain and opp. leg flexes up
Brudzinski
lift neck up
+ if pain and knees bend
Neisseria meningitis strains (meningococcal meningitis)
Groups A, B, C, Y, W-135
Vaccine does NOT cover serogroup B
40% of healthy hosts are nasopharyngeal carriers of meningococci
*most serious life-threatening form of bac meningitis
what to do with pt
Blood cultures, CT/MRI of brain, lumbar puncture
Do not delay IV antibiotics!
-ceftriaxone, vancomycin
Continue IV dosing until patient is afebrile for 4-5 days
steroids?
should be given early if given at all
- controversial
dec. ototoxicity
ppx?
close contacts
roommates, family in same house, HC workers w. intimate close contact
*droplet zone, i.e. person who intubated infected person
Rifampin x4
*Ciprofloxacin
Certriaxone IM (preggos)
if preg think ceph!
fever, ha, neck pain vomited 2x this morning Z-pack for CAP (think Strep pneumo) CT brain, LP empiric abx
2700 WBCs (94% segmented neutrophils)
Protein 220 mg/dL high
Glucose 18mg/dL (serum is 130mg/dL) low
Gram stain reveals Gram positive diplococci
bacterial
pneumococcal meningitis
Most common bacterial agent of meningitis in adults;
if + blood culture consider HIV testing
Gram positive diplococci
No rash, though purpura fulminans in overwhelming sepsis
extremes for pneumococcal meningitis
Extremes of age, CSF leaks, sinusitis/otitis (bac spreads), alcoholism, splenectomy, multiple myeloma patients
tx
Ceftriaxone 2gm IV q12h
Vancomycin 15mg/kg IV load
Steroids?
dexamethaxone
1st 4 days
listeria meningitis
G+ rod
Extremes of age, patients with cell mediated immunosuppression
Hodgkin’s disease, HIV, PREGNANCY
listeria preceding FBI
Pregnant patients are occasionally advised to avoid lunchmeats and soft cheeses due to the risk of listeria
tx for listeria men.
IV ampicillin or IV meropenem
include AMP empirically if listeria extremes
G+ coccus that causes meningitis
Streptococcus pneumoniae (pneumococcus). This bacterium is the most common cause of bacterial meningitis in infants, young children and adults in the United States
G- coccus that causes meningitis
Neisseria meningitidis (meningococcus)
Cryptococcal meningitis
india ink stain, “bubbly”
Subacute headache in HIV+ patient Buzz words: Pigeon droppings, construction Few lymphocytes in CSF \+ India ink \+ Cryptococcal Ag in CSF, serum, urine
Cryptococcal meningitis tx
Amphotericin B, +/- flucytosine; fluconazole (HIV+: on for rest of life if have mening. 2x!)
Shunt Associated Meningitis
Be suspicious of skin flora in aspiration of shunt
Coagulase negative staph
Propionibacterium species
Corynebacterium species
Do not presume “contaminants” as you may conclude if these organisms were seen in blood cultures
G- rod that causes meningitis
Haemophilus influenzae (haemophilus)
Gram Negative Meningitis
Neurosurgical patients - including insertion of pressure monitors, drains
Head trauma/skull fracture–>open portal
Remote focus (diverticulitis?)-->smolders (i.e. E. coli)-->enter blood-->enters CSF (may not just be UTI if bac in blood-Gall bladder)
Extremes of age
Following prophylaxis for CSF leak
Gram positives empirically covered, select out for gram negative infections*
G+ rod that causes meningitis
Listeria monocytogenes (listeria)
recurrent memingitis: mollaret’s
women 40-60
HSV 1?, HSV 2?, epidermoid cyst?
recurrent meningitis
Parameningeal focus - infection, epidermoid cyst, craniopharyngioma
CSF leak, often following trauma
Pneumococcus most common
recurrent meningitis: terminal ??
complement deficiencies
recurrent meningitis other presentations
SLE, migraines
med-caused “aseptic” meningitis
NSAID’s, azathioprine trimethoprim/sulfa, fluconazole
non-inf. etiology “aseptic” meningitis
Ca, AI
“Aseptic” Meningitis: VIRAL
Viral, difficult to culture organisms
R/O primary HIV infection (part of acute retroviral syndrome)
R/O primary genital herpes
Usual Aseptic culprits
Enteroviruses (Echo, coxsackie, polio, etc.)
Herpes (HSV, VZV, EBV, CMV)
Arboviruses (West Nile)
Lyme disease
Adenovirus
Lymphocytic choriomeningitis virus
Possible spirochetes? (leptospira, neurosyphilis, borrelia, etc.)
Acute Retroviral Syndrome
Fever, chills, myalgias Lymphadenopathy Rash - maculopapular Pharyngitis N/V, diarrhea -looks like mono
*Headache (if LP -> mild pleocytosis)
Elevated LFT’s
**HIV 1/2 Ab may be +/- or indeterminate
what’s missing in acute retroviral syndrome?
upper resp. symptoms
West nile virus
2-15 day incubation period
Most of the illness is the fever component
Fever/headache (~3/4) Muscle weakness and/or pain (~2/3) Rash (~3/4) Adenopathy Joint pain N/V, diarrhea (which may be severe, prolonged) Eye pain
west nile dx
Serologies for WNV IgM, IgG in the blood
“Summer surveillance” panels available seasonally
west nile risks
West coast, standing water
Neurologic west nile virus
Meningitis – fever, nuchal rigidity, CSF pleocytosis
Encephalitis – mental status changes
(Meningo-encephalitis)
waxing-waning
Acute flaccid paralysis (polio-like), seizures, other neurologic syndromes
CNS involvement within 24-48 hours of fever onset
Neurologic West Nile Virus
Greatest predictor of severe disease ?
is advanced age – mortality higher if patient >75yo
Dx: CSF IgM antibody for WNV
WNV tx
None known to be effective, including ribavirin, interferon or steroids-still given!
No vaccine yet available
IVIG with high titers of WNV antibody??
WNV assoc.
Transplantation Transfusion Breastfeeding Transplacental transmission Occupational exposure
Most common tick borne infection in the United States
Borrelia burgdorferi (Lyme)
target, erythema migraines
flu-like, fever, ha, aches
dx HSV encephalitis
by CSF HSV PCR
classically HSV-1
Neurologic status at time of treatment predicts prognosis
HSV encephalitis
acyclovir
HSV encephalitis
Fever, bizarre behavior, focal TEMPORAL lobe findings including seizure and MRI abnormalities
focal CNS disease in HIV: toxoplasmosis
Acute onset, fever, +serology, multiple contrast + lesions with mass effect
focal CNS disease in HIV: lymphoma EBV PCR+
Subacute onset, no fever, SINGLE contrast + lesion with mass effect
Progressive Multifocal Leukoencephalopathy
JC virus with +PCR
Indolent, no fever, contrast negative lesions WITHOUT mass effect
PRION diseases
Buzz word “slow virus”
Transmissible agent is a prion – devoid of nucleic acid
Creutzfeld-Jacob Disease Classic, Familial (14-3-3 protein found in CSF) Bovine Spongiform Encephalopathy (vCJD) Diagnosis by brain biopsy Kuru Scrapie Fatal Familial Insomnia
additional ddx
Botulism: diploplia, descending paralysis
Use of “black tar” heroin
Home-canned foods; toxin is heat labile
Polio - mutant strains of oral vaccine, biowarfare
Bell’s palsy – associated with HSV-1, also consider Lyme, HIV
Tick paralysis
Treatment? pull off
neuro lyme disease: early dissem. inf
Days to weeks later – facial palsy, meningitis, headache, encephalitis, cardiac manifestations (AV block)
LP + Lyme Ab – treated with 4 weeks of IV ceftriaxone 2gm q24h
neuro lyme disease: Late disseminated infection
Months later – severe, chronic polyneuropathy, chronic encephalomyelitis, somatoform delusions
“Chronic Lyme Disease”
Poorly understood, symptomatically managed
HSV encephalitis LP
LP may be initially normal
CLASSICALLY with high RBCs
“bloody tap”
causes of chronic meningitis
Tuberculosis
Fungal (candida, cryptococcus, aspergillus)
Lyme disease
Spirochete (syphilis, leptospirosis)
Toxoplasma
Non-infective (leukemia, SLE, tumor cells)
brain abscess
Classically with headache, high fever
Think Strep viridans species (poor dentition?)
Anaerobes
Staph aureus (including MRSA) with trauma, IVDA patients
Think fungal, yeast in diabetics, IVDA, neutropenic hosts
Mucormycosis
Candida
Aspergillus
epidural abscess
Fever
Back pain
Neurological deficit (if absent – consider vertebral osteomyelitis, discitis)
*S. aureus including MRSA most common
High ESR/CRP -monitor for normalization
At surgery, granulation tissue common
Epidural phlegmon-sticky material
primary amebic encephalitis:
change in smelling things after water skiing
Think Naegleria fowleri
Following swimming in warm, fresh water
Migration via olfactory nerve
Suspect if change in taste or smell
Tx: Amphotericin B (+ azithromycin?)
Almost universally fatal
