Table 2.
Proportion of Bacterial Detections Based on Specimens Collected Before and After Inpatient and/or Prehospital Antibiotics for Each Diagnostic Test
| Diagnostic Tests | Specimens Obtained Before Antibiotics | |||||
|---|---|---|---|---|---|---|
| Yes (%) | No (%) | |||||
| Adult | Child | Total | Adult | Child | Total | |
| Blood cultures, n | 1515 | 1164 | 2679 | 567 | 725 | 1292 |
| Total bacterial detections | 102 (6.7)a | 37 (3.2) | 139 (5.2)d | 19 (3.4) | 14 (1.9) | 33 (2.6) |
| Streptococcus pneumoniae | 37 (2.4) | 18 (1.5)c | 55 (2.1)c | 7 (1.2) | 2 (0.3) | 9 (0.7) |
| Streptococcus pyogenes | 4 (0.3) | 3 (0.3) | 7 (0.3) | 2 (0.4) | 1 (0.1) | 3 (0.2) |
| Streptococcus aureus | 18 (1.2) | 3 (0.3) | 21 (0.8) | 3 (0.5) | 3 (0.4) | 6 (0.5) |
| Haemophilus influenzae | 7 (0.5) | 1 (0.1) | 8 (0.3) | 2 (0.4) | 2 (0.3) | 4 (0.3) |
| Other pathogensa | 36 (2.4)c | 13 (1.1) | 49 (1.8)c | 5 (0.9) | 7 (1.0) | 12 (0.9) |
| High-quality sputum or ET cultures, n | 13 | 23 | 36 | 260 | 132 | 392 |
| Total bacterial detections | 2 (15.4) | 16 (69.6) | 18 (50.0)c | 29 (11.2) | 76 (57.6) | 105 (26.8) |
| S pneumoniae | 2 (15.4) | 4 (17.4) | 6 (16.7) | 11 (4.2) | 18 (13.6) | 29 (7.4) |
| S pyogenes | 0 (0.0) | 1 (4.3) | 1 (2.8) | 3 (1.2) | 3 (2.3) | 6 (1.5) |
| S aureus | 0 (0.0) | 6 (26.1) | 6 (16.7) | 11 (4.2) | 29 (22.0) | 40 (10.2) |
| H influenzae | 0 (0.0) | 6 (26.1) | 6 (16.7)c | 0 (0.0) | 23 (17.4) | 23 (5.9) |
| Other pathogensb | 0 (0.0) | 10 (43.5)c | 10 (27.8)d | 4 (1.5) | 32 (24.2) | 36 (9.2) |
| Urine antigen test, n (only performed in adults) | 158 | 158 | 1757 | 1757 | ||
| Total detections | 11 (7.0) | NA | 11 (7.0) | 101 (5.7) | NA | 101 (5.7) |
| Pneumococcal antigen detection | 7 (4.4) | NA | 7 (4.4) | 74 (4.2) | NA | 74 (4.2) |
| Legionella antigen detection | 4 (2.5) | NA | 4 (2.5) | 26 (1.5) | NA | 26 (1.5) |
| Combined pneumococcal and Legionella antigen detections | 0 (0.0) | NA | 0 (0.0) | 1 (0.1) | NA | 1 (0.1) |
| NP/OP swab PCR assay, n | 126 | 279 | 405 | 2118 | 1707 | 3825 |
| Total Mycoplasma pneumoniae or Chlamydia pneumoniae detections | 7 (5.6)c | 20 (7.2) | 27 (6.7) | 45 (2.1) | 163 (9.5) | 208 (5.4) |
Abbreviations: ET, endotracheal tube; NA, nonapplicable; NP/OP, nasopharyngeal and oropharyngeal; PCR, polymearase chain reaction.
Columns may not add to 100% because some specimens may have had more than 1 pathogen detected. The following bacteria were considered contaminants and were excluded from the analyses: Aeroccocus, Alcaligenes, Bacillus, Citrobacter, coagulase-negative Staphylococcus, Corynebacterium, Enterococcus, Micrococcus, Neisseria subflava, Propionibacterium, Stomatococcus, Streptococcus bovis, and Veillonella.
Other pathogens (specimens before antibiotics: yes/no): Escherichia coli (13/0); viridans streptococci species (9/4); Klebsiella (6/0); streptococcal groups B, C, or G (7/3); Fusobacterium (3/1); Pseudomonas (2/1); Moraxella (1/1); Acinobacter (2/0); Enterobacter (1/0); Pasteurella (1/0); Proteus (1/0); or codetections (3/2).
Other pathogens (specimens before antibiotics: yes/no): Moraxella (10/30), Pseudomonas (0/4), E coli (0/1), Enterobacter (0/1).
P value <.05 compared with specimens obtained after antibiotics.
P value <.001 compared with specimens obtained after antibiotics.