Table 4.

Description of 16 clinical specimens which were negative by broad-range bacterial PCR assay and positive by culture as well as clinical data regarding the results of blood cultures, administration of antimicrobial therapy, and the final clinical diagnosis for the patient

Specimen no.SpecimenPCR resultCulture findingaGram staining resultbBlood culture resultcAntimicrobials therapydFinal diagnosis
1CSFe Streptococcus pneumoniae(+) S. pneumoniae NoBacterial meningitis
2CSF S. pneumoniae(+)NoBacterial meningitis
3CSF Streptococcus mitis (+++)GPC (+)NDf YesBacterial meningitis
4CSF Streptococcus agalactiae (+)GPC (+) S. agalactiae NoBacterial meningitis
5ag CSF P. acnes(+++)GPR (++) P. acnes NoCerebrospinal shunt infection
5bg CSF P. acnes(+++)ND
6CSF Listeria monocytogenes(+) L. monocytogenes NoBacterial meningitis
7CSF Mycobacterium tuberculosis NoTuberculous vasculitis
8Pleural fluid S. aureus (+)NDYes (6 days)Pneumonia and pleural empyema
9Pleural fluid Streptococcus pyogenes (+++)GPC (++)Yes (1 day)Pneumonia and pleural empyema
10Pus from empyema S. aureus (+++)GPC (+)Yes (3 days)Postoperative subdural empyema
11Pus from middle ear S. aureus(+++)NDNDNoChronic otitis media
12Pus from spinal abscess P. aeruginosa (++) P. aeruginosa YesPostoperative spondylodiscitis and spinal abscess
13Pus from spinal abscess M. tuberculosis YesTuberculous spondylitis
14Pus from knee joint M. tuberculosis AFB (+)NoMiliary tuberculosis with bone involvement
15Pus from soft tissue Mycobacterium avium No M. avium abscess
  • a Symbols in parentheses are relative number of colonies on the primary culture plate; +, few; ++, moderate; +++, many.

  • b For patients 13 and 14, auramine-rhodamine stain. GPC, gram-positive cocci; GPR, gram-positive rods; AFB, acid-fast bacilli. Symbols in parentheses are relative number of cells seen in the strain: +, few; ++, moderate; +++, many.

  • c On the same day (±2 days) as the specimen for the PCR assay and culture was taken.

  • d The durations that antimicrobial therapy was effective against the microbe recognized in the specimen are given in parentheses. Patients 3, 12, and 13 received ineffective therapy.

  • e CSF, cerebrospinal fluid.

  • f ND, the test was not done.

  • g Two successive cerebrospinal fluid samples, designated samples 5a and 5b, were obtained from patient 5.