13 CNS and Spinal Infections

Question 1

Most common symptom of meningitis

Answer 1

Headache

Question 2

Contraindication to performing a lumbar puncture on an emergent basis

Answer 2

platelet count ≤20,000
or INR ≥1.5

Question 3

Bacterial meningitis features on CSF

Answer 3

Opening pressure >170 mm H2O
WBC >1000/mm3
Neutrophilic predominance
Protein >200 mg/dL
Glucose <40 mg/dL
or glucose serum-to-CSF ratio <0.4

Question 4

Sterilization of CSF is possible within

Answer 4

2 hours of initiating parenteral antibiotics in meningococcal
and 6 hours in pneumococcal meningitis
highlighting the importance of timely LP

Question 5

Remarks on bacterial meningitis

Answer 5

When bacterial meningitis is considered, never withhold empiric antibiotic therapy in order to collect the CSF sample

Question 6

Criteria for obtaining head CT before lumbar puncture

Answer 6

Altered mental status or deteriorating level of consciousness
Bulbar signs
Czure (new-onset seizure)
Deficit (Focal neurologic deficit)
Emmunocompromised state
F**reexisting focal CNS disease (stroke, focal infection, tumor)
**Fapilledema
AG*e >60y
Malignancy
Concern for mass CNS lesion

Question 7

Presumed bacteria for immunocompetent meningitis patient

Answer 7

S pneumoniae and N meningitidis

Question 8

Empiric therapy for immunocompetent meningitis patient

Answer 8

Cefotaxime or ceftriaxone
+ Vancomycin 15-20 mg/kg IV

Question 9

If severe penicillin allergy exists for immunocompetent meningitis patient

Answer 9

can replace ceftriaxone with meropenem 2 g IV or moxifloxacin 400 mg IV

Question 10

Presumed bacteria for immunocompromised or age >50y meningitis patient

Answer 10

Listeria monocytogenes

Question 11

Empiric therapy for immunocompromised or age >50y meningitis patient

Answer 11

Cefotaxime or ceftriaxone
+ vancomycin 15-20 mg/kg
+ ampicillin 2g IV

Question 12

If severe penicillin allergy exists for immunocompromised or age >50y meningitis patient

Answer 12

Can replace ampicillin with trimethoprim-sulfamethoxazole 15-20 mg/kg/day divided 4x daily

Question 13

Presentation of brain abscess

Answer 13

Generally nontoxic, and nonspecific
Classic triad (25%):
- headache (most common)
- fever
- focal neurologic deficit

Question 14

Imaging in brain abscess

Answer 14

brain abscess is one instance where a contrast-enhanced head CT scan is preferred over a noncontrast study in the ED

Question 15

Management principles in brain abscess

Answer 15

Early comibnation empiric antibiotics
Multidisciplinary approach with neurosurgery and infectious disease consultations

Question 16

Primary empiric therapy for brain abscess with otogenic source

Answer 16

Ceftoaxime 2g IV q 4-6 h
or ceftriaxone 2 g IV q 12
+ metronidazole 500mg IV q8

Question 17

Primary empiric therapy for brain abscess with odontogenic source

Answer 17

Penicillin G 4 million units IV every 4 h

Question 18

Primary empiric therapy for brain abscess after neurosurgical procedure

Answer 18

Vancomycin or linezolid
+ ceftazidime
+/- rifampin

Question 19

Primary empiric therapy for brain abscess with unknown source

Answer 19

ceftaxime 2g IV q6
+ metronidazole 500mg IV q6

Question 20

May be treated with IV antibiotics alone

Answer 20

Small abscesses <2.5 cm
GCS ≥13
Known etiology (aspiration may be done by neurosurgical team to elucidate the causative organism)