Aetiology determined by routine microbiological research and serological investigation
| Aetiology | PDT (n = 134) | EAT (n = 128) | Total (n = 262) |
|---|---|---|---|
| PDT, pathogen directed treatment group; EAT, empirical antibiotic treatment group. | |||
| *Nine cases of Legionnaire’s disease (six in the PDT group and three in the EAT group) were the result of a visit to a flower exhibition in Bovenkarspel, the Netherlands. | |||
| †Gram negative Enterobacteriaceae: PDT: E coli (2×). EAT, definitive diagnoses: E coli (1×), Enterobacter cloacae (1×). EAT, presumptive diagnoses: E coli (1×), Enterobacter aeruginosa (1×), Klebsiella pneumoniae (1×), Citrobacter freundii (1×), Klebsiellla oxytoca (1×), Morganella morgagnii (1×), E cloacae (1×). | |||
| ‡PDT: Haemophilus parainfluenzae (2×), Pseudomonas aeruginosa (1×), α-haemolytic streptococcus (1×). EAT, definitive diagnoses: Arcanobacterium haemolyticum (1×) and streptococcus group C (1×). EAT, presumptive diagnoses: P aeruginosa (1×), streptococcus group B (1×), Staphylococcus epidermidis (1×). | |||
| ¶Mixed infection consisted of a typical bacterial pathogen and a definitive atypical bacterial or viral pathogen. | |||
| Streptococcus pneumoniae, n (%) | 49 (37) | 43 (34) | 92 (35) |
| Definitive | 16 | 15 | 31 |
| Presumptive | 33 | 28 | 61 |
| Mycoplasma pneumoniae, n (%) | |||
| Definitive | 13 (10) | 10 (8) | 23 (9) |
| Haemophilus influenzae, n (%) | 13 (10) | 6 (5) | 19 (7) |
| Definitive | 0 | 3 | 3 |
| Presumptive | 13 | 3 | 16 |
| Legionella pneumophila*, n (%) | |||
| Definitive | 7 (5) | 7 (5) | 14 (5) |
| GNEB†, n (%) | 2 (1) | 9 (7) | 11 (4) |
| Definitive | 0 | 2 | 2 |
| Presumptive | 2 | 7 | 9 |
| Staphylococcus aureus, n (%) | 6 (4) | 4 (3) | 10 (4) |
| Definitive | 2 | 4 | 6 |
| Presumptive | 4 | 0 | 4 |
| Moraxella catarrhalis, n (%) | |||
| Presumptive | 7 (5) | 0 | 7 (3) |
| Viral infection, n (%) | |||
| Definitive | 4 (3) | 6 (5) | 10 (4) |
| Chlamydia pneumoniae, n (%) | |||
| Definitive | 1 (<1) | 0 | 1 (<1) |
| Other‡, n (%) | 4 (3) | 5 (4) | 9 (3) |
| Definitive | 0 | 2 | 2 |
| Presumptive | 4 | 3 | 7 |
| Mixed infection¶, n (%) | 7 (5) | 10 (8) | 17 (6) |
| Unknown, n (%) | 50 (37) | 59 (46) | 109 (42) |