Table 1.
Baseline characteristics of patients with community-acquired (CAL) and hospital-acquired legionellosis (HAL).a
| CAL | HALb | ||
|---|---|---|---|
| Characteristic | No. (%) (n = 272)c | No. (%) (n = 60)c | p-valued |
| Demographics | |||
| Male sex | 181 (66.5) | 33 (55.0) | 0.09 |
| Age, median years (IQR) | 57 (50-70) | 67 (57-74) | 0.003* |
| Age group | 0.002* | ||
| ≤ 65 years | 185 (68.0) | 28 (46.7) | |
| > 65 years | 87 (32.0) | 32 (53.3) | |
| Exposure | |||
| Associated with travelling to another countrye | 92 (33.8) | 0 (0) | <0.001* |
| Exposure to air-conditioning | 33 (12.1) | 0 (0) | 0.004* |
| Part of a possible outbreak of legionnaires' disease | 2 (0.7) | 1(1.7) | 0.49 |
| Comorbid illnesses | |||
| Charlson Comorbidity Index | <0.001* | ||
| = 0 | 170 (62.5) | 13 (21.7) | |
| = 1 | 61 (22.4) | 12 (20.0) | |
| ≥ 2 | 41 (15.1) | 35 (58.3) | |
| Current smoker | 147 (54.0) | 17 (28.3) | 0.002* |
| Current alcohol abuse | 30 (11.0) | 7 (11.7) | 0.65 |
| Selected symptoms and signs | |||
| Temperature >39.5°C | 143 (52.6) | 7 (11.7) | <0.001* |
| Depressed consciousness | 64 (23.5) | 5 (8.3) | 0.17 |
| X-ray findings | |||
| Abnormal chest X-ray | 250 (91.9) | 48 (80.0) | 0.001* |
| Unilateral infiltrate | 188 (69.1) | 37 (61.7) | 0.20 |
| Bilateral infiltrates | 54 (19.9) | 9 (15.0) | 0.36 |
| Severity of illness | |||
| Pneumonia severity index (PSI) risk class | 0.74 | ||
| I | 19 (7.0) | 3 (5.0) | |
| II | 65 (23.9) | 18 (30.0) | |
| III | 76 (27.9) | 15 (25.0) | |
| IV | 95 (34.9) | 19 (31.7) | |
| V | 15 (5.5) | 5 (8.3) | |
| CURB-65 score | 0.62 | ||
| O | 119 (43.8) | 21 (35.0) | |
| I | 98 (36.0) | 23 (38.3) | |
| II | 39 (14.3) | 12 (20.0) | |
| III | 10 (3.7) | 3 (5.0) | |
| IV | 2 (0.7) | 1 (1.7) | |
| Diagnosis | |||
| Duration of in-hospital symptoms to relevant diagnostic test for legionellosis, median (IQR) | 3 (1-5) | 7.5 (4-15.5) | <0.001* |
| Duration of in-hospital symptoms to diagnosis of legionellosis, median (IQR) | 5.5 (4-9) | 12 (7-17) | <0.001* |
a See additional file 1 for more baseline characteristics
b Defined as hospital-acquired if the patient had been admitted within the preceding 10 days or if the patient developed symptoms
of legionellosis more than 2 days after hospital admission.
c Totals may not add up to 100% due to missing values
d Differences between the groups were analyzed with χ2 or Fisher's exact test as appropriate for categorical variables.
Continuous variables were compared using two-sample t-test (normal distribution) or Mann-Whitney U-test (non-normal distribution).
e Defined as possible travel-associated if the patient had travelled to a foreign country within 10 days of onset of symptoms.
IQR: Interquartile range.
* P-level < 0.05 is considered statistically significant.