Table 3 Demographic and serological data among LD patients diagnosed by acute phase tests and serology
From: Characterization of the extent of a large outbreak of Legionnaires’ disease by serological assays
Positive culture/PCR/UAT (n = 56) | Positive serology only (n = 47) | P-value | |
|---|---|---|---|
Age, mean years ± SD | 69 ± 14 | 65 ± 12 | 0.15 |
Male gender | 34 (61) | 30 (64) | 0.75 |
Chronic respiratory disease | 11 (20) | 11 (23) | 0.64 |
Active smoker | 22 (39) | 17 (36) | 0.69 |
Previously healthy | 20 (36) | 18 (38) | 0.79 |
Date of symptom onset | 16. May | 16. May | |
(interquartile range [IQR]) | (14.–19. May) | (14.–19. May) | 0.90 |
Inpatient treatment | 55 (98) | 45 (96) | 0.45 |
C-reactive protein (mg/L) ± SD | 296 ± 116 | 237 ± 89 | 0.15 |
ICU-admission | 19 (34) | 2 (4) | <0.001 |
CRB-65 score ≥2 | 33 (59) | 16 (34) | 0.012 |
Infiltrate > one lobe | 13 (23) | 9 (19) | 0.83 |
Mortality | 10 (18) | 0 (0) | 0.002 |
IFA-titre, acute phase | 64 (0 – 256) | 32 (0 – 64) | 0.16 |
IFA-titre, after 1 month | 256 (64 – 1024) | 128 (128 – 256) | 0.11 |
IFA titre, after 3 months | 128 (32 – 1024) | 64 (32 – 128) | 0.15 |
ELISA IgG, acute phase | 41 (10 – 115) | 20 (9 – 52) | 0.25 |
ELISA IgG, after 1 month | 53 (27 – 188) | 66 (30 – 193) | 0.96 |
ELISA IgG, after 3 months | 60 (17 – 312) | 33 (12 – 131) | 0.20 |
ELISA IgM, acute phase | 24 (4 – 93) | 8 (3 – 150) | 0.15 |
ELISA IgM, after 1 month | 47 (22 – 195) | 29 (16 – 87) | 0.11 |
ELISA IgM, after 3 months | 21 (10 – 76) | 11 (6 – 30) | 0.04 |