The approach to therapy in patients with pneumococcal meningitis has changed considerably over the past 20 years. Given the emergence of pneumococcal strains that are intermediately susceptible or highly resistant to penicillin, penicillin is not recommended as empiric therapy for presumed pneumococcal meningitis; the combination of vancomycin and a third-generation cephalosporin (either cefotaxime or ceftriaxone) should be used, pending isolation of the organism and in vitro susceptibility testing. For patients with pneumococcal meningitis caused by highly penicillin- or cephalosporin-resistant strains, the addition of rifampin can be considered if the organism is susceptible in vitro, the expected clinical or bacteriologic response is delayed, or the pneumococcal isolate has a cefotaxime or ceftriaxone minimal inhibitory concentration greater than 4 μg/mL. Meropenem is not a good option for monotherapy of highly penicillin- or cephalosporin-resistant strains, but use of a fluoroquinolone with in vitro activity against Streptococcus pneumoniae (specifically moxifloxacin) is an option in patients failing standard therapy; if used, however, it should be combined with a third-generation cephalosporin or vancomycin. Newer glycopeptides, daptomycin, and linezolid require further study to determine their efficacy in patients with pneumococcal meningitis.

Background. Clinical microbiology references suggest that cultures for anaerobic bacteria should be incubated for 5 days (d); however, little data exist to support this recommendation. A Quality Assurance (QA) study performed in our laboratory in 1992 revealed that most anaerobes were detected within 2 d and that the incremental yield of 5 d of incubation was negligible. We have repeated this analysis using contemporary reagents and methods to reevaluate the relative yield of anaerobes after 2 d vs 5 d of incubation. In addition, we assessed the clinical utility of the identification of isolates grown after 2 d of incubation.Methods. We performed an 8 month prospective QA study between August 1, 2013, and March 31, 2014. Specimens from sterile body fluids; wounds, tissues, abscesses, aspirates and operative specimens were inoculated to appropriate media, and placed into chambers with anaerobic atmosphere generated by the Anoxamat system. Cultures were incubated for 2 d before being examined.Cultures that showed no growth after 2 d were re-incubated for an additional 3 d and then re-examined at 5 d. Chart review was performed on anaerobic cultures that were positive only after 5 d.Results. A total of 2107 anaerobic cultures were processed during the study period, of which 177 specimens (8.3%) grew anaerobes. Only 2 (1.2%) were positive at 5 d and not at 2 d; 175/177 (99.4%) anaerobes were detected after 2 d of incubation. Propionibacterium acnes was isolated from the 2 positive specimens that grew only after 5 d of incubation. One of the 2 P. acnesisolates, which was from brain tissue, was judged to be clinically important. Thus, 1 of 177 clinically important anaerobic cultures (0.6%) would have been missed with a 2 d incubation protocol.Conclusion. Our results generally confirm observations from two decades ago. We conclude that the great majority of anaerobic cultures will show growth within 2 d of incubation. Rarely, particularly for P. acnes,longer incubation (e.g., 5 d) is needed. Infectious Diseases physicians should be aware of incubation protocols in their Microbiology labs and may wish to request extended incubation when clinically indicated. In an era of cost containment, in-house QA studies can enhance cost effective microbiology.Disclosures. All authors: No reported disclosures.Poster Abstracts • OFID 2014:1 (Suppl 1) • S369 Downloaded from https://academic.oup.