Specimens with and without classic bacterial meningitis-causing organisms and number not detected by BAT and Gram stain

OrganismTotal no. of specimensNo. (%) of specimens not detected by:
BATGram stain
Detected by culturea
    Streptococcus pneumoniae 226 (27)3 (14)
    Group B Streptococcus species73 (43)0 (0)
    Neisseria meningitidis 73 (43)1 (14)
    Haemophilus influenzae type b20 (0)1 (50)
Not detected by cultureb 41 (25)0 (0)
Total4213 (31)5 (12)
  • a Growth from cerebrospinal fluid, blood, or ear drainage specimens.

  • b Results of both the BAT and the Gram stain were positive for three specimens, with results indicating N. meningitidis in two and S. pneumoniae in one. In one specimen, the Gram stain showed Gram-positive cocci resembling streptococci, the BAT was negative, and the urine pneumococcal antigen test was positive.