CNS Infections

Question 1

Bacterial Meningitis Triad

Answer 1

Fever: most (95%) have high–>38 C ‏
Nuchal rigidity (88%)‏
Change in mental status (lethargy most common)

Question 2

Kernig sign:

Answer 2

supine position, flex hip 90 degrees, inability or reluctance to allow full extension of the knee when the hip is flexed

Question 3

Brudzinski sign

Answer 3

spontaneous flexion of hips during attempted passive flexion of the neck

Question 4

LP findings in bacterial meningitis

Answer 4

Elevated opening pressure (70-150)
Cloudy, purulent appearance
Leukocytosis (1000 to 5000, with > 80% neutrophils)
Protein of 100 to 500 mg/dL (15-45)
glucose <40 mg/dL (45-85)

Question 5

Tx. Mainly aimed at S. pneumoniae and meningococcal…College in dorms

Answer 5

Cefotaxime (Claforan) or ceftriaxone (Rochephin) + vancomycin

Question 6

For L monocytogenes (age >50) Tx.

Answer 6

Ampicillin or penicillin alternative in pcn allergic pts is Trimethoprim-sulfamethoxazole (TMP-SMX)

Question 7

Noscomial Tx.

Answer 7

Ceftazidime + vancomycin

Question 8

Aseptic Meningitis

Answer 8

Presentation: Fever, HA, stiff neck and photophobia
Contrast to bacterial meningitis: Aseptic meningitis is a self-limited course that resolves without specific therapy
Etiologic agents: Enteroviruses, HSV, HIV, West Nile, RMSF etc.

Question 9

Viral Encephalitis CSF Findings

Answer 9

May have increased WBCs with differential showing mostly lymphocytes
Elevated protein, but < 150 mg/dL
Normal glucose

Question 10

West Nile Virus

Answer 10

Fever, Malaise, Stiff neck, sore throat
Signs of an upper motor neuron lesion (exaggerated DTRs, absent superficial reflexes, pathologic reflexes, and spastic paralysis)
severe neurological disease
Treatment is supportive and RIBAVARIN

Question 11

Brain Abscess Triad

Answer 11

HA, fever, focal deficit

Question 12

Brain Abscess Treatment

Answer 12

Cefotaxime + Flagyl