<prompt> A 45-year-old female is diagnosed as a case of pneumococcal meningitis. Her blood samples were sent for culture sensitivity. In the mean time best drug to start as an empirical treatment is:Penicillin GDoxycyclineStreptomycinVancomycin ceftriaxone  <response>: Ans. d. Vancomycin ceftriaxone Ref: Harrison 19e p889, 18e p3416Antimicrobial therapy of pneumococcal meningitis is initiated with a cephalosporin ceftriaxone, cefotaxime, or cefepime and vancomycin.Antimicrobial therapy of pneumococcal meningitis is initiated with a cephalosporin ceftriaxone, cefotaxime, or cefepime and vancomycin. For S. pneumoniae meningitis, an isolate of S. pneumoniae is considered to be susceptible to penicillin with a minimal inhibitory concentration MIC 0.06 mgmL, to have intermediate resistance when the MIC is 0.1 -1.0 mgmL, and to be highly resistant when the MIC 1.0 mgmL. Isolates of S. pneumoniae that have cephalosporin MICs _0.5 mgmL are considered sensitive to the cephalosporins cefotaxime, ceftriaxone, cefepime. Those with MICs of 1 mgmL are considered to have intermediate resistance, and those with MICs _2 mgmL are considered resistant. For meningitis due to pneumococci, with cefotaxime or ceftriaxone MICs 0.5 mgmL, treatment with cefotaxime or ceftriaxone is usually adequate. For MIC 1 mgmL, vancomycin is the antibiotic of choice; Rifampin can be added to vancomycin for its synergistic effect but is inadequate as monotherapy because resistance develops rapidly when it is used alone.- Harrison 18e p3416A 2-week course of intravenous antimicrobial therapy is recommended for pneumococcal meningitis.- Harrison 18e p3416Patients with penicillin- and cephalosporin-resistant strains of S. pneumoniae who do not respond to intravenous vancomycin atone may benefit from the addition of intraventricular vancomycin. The intraventricular route of administration is preferred over the intrathecal route because adequate concentrations of vancomycin in the cerebral ventricles are not always achieved with intrathecal administration.- Harrison 18e p3416Antimicrobial Therapy of CNS Bacterial Infections Based on PathogensOrganismAntibioticNeisseria meningitidesPenicillin-sensitive Penicillin G or ampicillinQPenicillin-resistant Ceftriaxone or cefotaximeQStreptococcus pneumoniaePenicillin-sensitive Penicillin GQPenicillin-intermediate Ceftriaxone or cefotaxime or cefepimeQPenicillin-resistant Ceftriaxone or cefotaxime or cefepime vancomycinQGram-negative bacilli except Pseudomonas spp. Ceftriaxone or cefotaximeQPseudomonas aeruginosa Ceftazidime or cefepime or meropenemQStaphylococci spp.Methicillin-sensitive NafcillinQMethicillin-resistant VancomycinQListeria monocytogenes Ampicillin gentamicinQHaemophilus influenzae Ceftriaxone or cefotaxime or cefepimeQStreptococcus agalactiae Penicillin G or ampicillinQBacteroides fragilis MetronidazoleQFusobacterium spp. MetronidazoleQ 