Correct!
4. Five to forty percent of pneumococcal isolates are intermediate or resistant to ceftriaxone, thus necessitating the addition of vancomycin.
Only patients who present with altered mental status, focal neurological findings, or seizures, and those who are immunocompromised or have known intracranial mass lesions, require a brain CT prior to lumbar puncture. The two most important treatment factors influencing patient outcome are the rapid administration of appropriate antibiotics (in most adults: ceftriaxone, 2gm Q12hourly and vancomycin 20mg/kg Q8hourly) and the initiation of dexamethasone 0.15mg/kg Q6hourly either before, or concomitantly with antibiotics. The optimal sequence is to immediately perform an LP and blood cultures, then start antibiotics. But antibiotics should not be delayed if the LP cannot be immediately performed. Antibiotics given >2 hours prior to LP can reduce the sensitivity of CSF gram stain and cultures, but this is a secondary concern.
Suspected community-acquired bacterial meningitis should not be ruled-out based on the lack of typical CSF findings such as in cases with leukocytosis <1000, neutrophils <80% or absence of severe hypoglycorrhachia or marked elevation of CSF protein, as these findings are not highly sensitive for the diagnosis. (Remember SPIN and SNOUT – high SPecificity is required to reliably rule a disease IN, high SeNsitivity to rule it OUT). Empirical treatment of community-acquired bacterial meningitis in patients >50 years of age, or those who are solid organ transplant recipients includes high dose ampicillin to cover L. monocytogenes.
Which of the following is false regarding adjunctive dexamethasone for community-acquired bacterial meningitis? (Click on the correct answer to be directed to the fourth of 5 pages)