Background
Methods
Study population and case definitions
Data collection
Specimen collection and laboratory testing
Statistical analysis
Results
Study population and microbiological diagnosis
Results | Mp -DNA (BALF) | Mp -DNA (NPA)a | IgG(paired sera) | NO. |
---|---|---|---|---|
Mp positive (N = 110) | + | + | / | 98 |
+ | + | + | 6 | |
+ | + | / | 6 | |
Mp negative (N = 4038) | – | + | / | 4 |
/ | + | / | 62 | |
/ | – | / | 3941 | |
/ | – | – | 31 |
Etiologic agents | Proportion (%) |
---|---|
Mp mono-detection | 68(61.82) |
Mp co-detection | 42(38.18) |
Virus | 30(27.27) |
Mp + HRV | 20 |
Mp + HPIV | 6 |
Mp + HRV + HPIV | 1 |
Mp + ADV | 1 |
Mp + HCoV | 1 |
Mp + H3 | 1 |
Bacteria | 7(6.36) |
Mp + S. pneumoniae | 1 |
Mp + S. epidermidis | 1 |
Mp + Alcaligenes spp | 1 |
Mp + A. baumannii | 1 |
Mp + Radioactive rhizobia | 1 |
Mp + S. viridans | 1 |
Mp + S. saprophyticus | 1 |
Bacteria and virus | 5(4.55) |
Mp + HRV + S. pneumoniae | 1 |
Mp + HMPV + S. marcescens | 1 |
Mp + ADV + S. hominis | 1 |
Mp + HBoV + K. oxytoca | 1 |
Mp + HMPV + HRV + A. baumannii | 1 |
Demographic characteristics
Characteristics | Mp (n = 68) | Mp-Vir (n = 30) |
P
| Mp-HRV (n = 20) |
P
| Mp-Vir (excluding HRV) (n = 10) |
P
| Mp-Bac (n = 7) |
P
|
---|---|---|---|---|---|---|---|---|---|
Age, median (IQR) (y) | 6 (3) | 4 (3) | 0.009 | 4 (3) | 0.004 | 5 (3.5) | 0.045 | 5 (5) | 0.514 |
≤1 year | 0 (0) | 1 (3.33) | 0.02 | 0 (0) | 0.011 | 1 (10) | 0.205 | 0 (0) | 0.52 |
1 to ≤3 years | 10 (14.71) | 10 (33.33) | 9 (45) | 1 (10) | 2 (28.57) | ||||
3 to ≤6 years | 30 (44.12) | 13 (43.33) | 8 (40) | 5 (50) | 3 (42.86) | ||||
> 6 years | 28 (41.18) | 6 (20) | 3 (15) | 3 (30) | 2 (28.57) | ||||
Sex, male | 37 (54.41) | 19 (63.33) | 0.411 | 13 (65) | 0.401 | 6 (60) | 1 | 4 (57.14) | 1 |
Seasons | |||||||||
Summer(6–8) | 18 (26.47) | 6 (20) | 0.929 | 5 (25) | 0.966 | 1 (10) | 0.705 | 2 (28.57) | 0.107 |
Autumn(9–11) | 24 (35.29) | 11 (36.67) | 6 (30) | 5 (50) | 0 (0) | ||||
Winter(12–2) | 17 (25) | 9 (30) | 6 (30) | 3 (30) | 4 (57.14) | ||||
Spring(3–5) | 9 (13.24) | 4 (13.33) | 3 (15) | 1 (10) | 1 (14.29) |
Clinical data, laboratory and radiographic findings
Characteristics | Mp (n = 68) | Mp-Vir (n = 30) |
P
| Mp-HRV (n = 20) |
P
| Mp-Vir (excluding HRV) (n = 10) |
P
| Mp-Bac (n = 7) |
P
|
---|---|---|---|---|---|---|---|---|---|
Clinical data | |||||||||
Fever | 68 (100) | 29 (96.67) | 0.306 | 20 (100) | – | 9 (90) | 0.128 | 7 (100) | – |
Days of total, median(IQR) (d) | 12 (7) | 14 (6) | 0.039 | 13.5 (8.75) | 0.212 | 16 (4.5) | 0.031 | 11 (7) | 0.935 |
Cough | 68 (100) | 28 (93.33) | 0.092 | 18 (90) | 0.05 | 10 (100) | – | 7 (100) | – |
Fatigue | 6 (8.82) | 6 (20) | 0.222 | 4 (20) | 0.325 | 2 (20) | 0.596 | 1 (14.29) | 0.512 |
Lack of appetite | 16 (23.53) | 14 (46.67) | 0.022 | 9 (45) | 0.061 | 5 (50) | 0.168 | 2 (28.57) | 1 |
Dyspnea | 7 (10.29) | 4 (13.33) | 0.927 | 2 (10) | 1 | 2 (20) | 0.714 | 1 (14.29) | 0.562 |
Chills | 4 (5.88) | 3 (10) | 0.761 | 2 (10) | 0.891 | 1 (10) | 0.506 | 1 (14.29) | 0.396 |
Headache | 3 (4.41) | 1 (3.33) | 1 | 1 (5) | 1 | 0 (0) | 1 | 0 (0) | 1 |
Sore throat | 66 (97.06) | 30 (100) | 1 | 20 (100) | 1 | 10 (100) | 1 | 7 (100) | 1 |
Wheezing | 1 (1.47) | 3 (10) | 0.158 | 2 (10) | 0.128 | 1 (10) | 0.241 | 0 (0) | 1 |
Runny nose | 0 (0) | 4 (13.33) | 0.012 | 4 (20) | 0.002 | 0 (0) | – | 0 (0) | – |
Abdominal pain | 3 (4.41) | 1 (3.33) | 1 | 1 (5) | 1 | 0 (0) | 1 | 1 (14.29) | 0.33 |
Diarrhea | 1 (1.47) | 0 (0) | 1 | 0 (0) | 1 | 0 (0) | 1 | 0 (0) | 1 |
Vomit | 3 (4.41) | 3 (10) | 0.544 | 2 (10) | 0.689 | 1 (10) | 0.429 | 0 (0) | 1 |
Chest pain | 5 (7.35) | 0 (0) | 0.305 | 0 (0) | 0.484 | 0 (0) | 1 | 0 (0) | 1 |
Rash | 2 (2.94) | 1 (3.33) | 1 | 1 (5) | 0.543 | 0 (0) | 1 | 0 (0) | 1 |
Laboratory findings | |||||||||
Leukocyte count, median(IQR) × 109/L | 10.35 (5.85) | 10.4 (5.8) | 0.691 | 10.4 (4.55) | 0.812 | 11 (12.2) | 0.639 | 12.4 (7.1) | 0.303 |
Neutrophils, median(IQR) (%) | 64.55 (13.58) | 59.9 (18.6) | 0.137 | 60.6 (18.25) | 0.142 | 58.55 (27.33) | 0.509 | 60 (16.5) | 0.549 |
Lymphocytes, median (IQR) (%) | 25.45 (12.03) | 27.5 (15.1) | 0.244 | 27.5 (19.45) | 0.133 | 23.45 (19.23) | 0.872 | 27.3 (17.1) | 0.888 |
C-reactive protein, median(IQR)(mg/L) | 20.6 (36.55) | 9.7 (34.45) | 0.063 | 9.3 (34.3) | 0.06 | 16.85 (58.15) | 0.459 | 8.7 (23) | 0.441 |
Radiographic findings | |||||||||
Single lobar infiltrate | 27 (39.71) | 12 (40) | 0.978 | 10 (50) | 0.412 | 2 (20) | 0.393 | 4 (57.14) | 0.625 |
Multilobar infiltrates (unilateral) | 19 (27.94) | 6 (20) | 0.406 | 3 (15) | 0.24 | 3 (30) | 1 | 0 (0) | 0.245 |
Multilobar infiltrates (bilateral) | 19 (27.94) | 12 (40) | 0.237 | 7 (35) | 0.543 | 5 (50) | 0.296 | 3 (42.86) | 0.697 |
Bronchitis | 3 (4.41) | 0 (0) | 0.551 | 0 (0) | 1 | 0 (0) | 1 | 0 (0) | 1 |
Hilar lymphadenopathy | 2 (2.94) | 3 (10) | 0.334 | 3 (15) | 0.134 | 0 (0) | 1 | 0 (0) | 1 |
Complications, underlying conditions and disease severity parameters
Characteristic | MP (n = 68) | Mp-Vir (n = 30) |
P
| Mp-HRV (n = 20) |
P
| Mp-Vir (excluding HRV) (n = 10) |
P
| Mp-Bac (n = 7) |
P
|
---|---|---|---|---|---|---|---|---|---|
Complicationsa | |||||||||
Any condition (≥1 condition) | 55 (80.88) | 29 (96.67) | 0.081 | 20 (100) | 0.078 | 9 (90) | 0.795 | 7 (100) | 0.454 |
Pleural effusion | 35 (51.47) | 13 (43.33) | 0.458 | 6 (30) | 0.091 | 7 (70) | 0.449 | 5 (71.43) | 0.542 |
Small | 1 (1.47) | 1 (3.33) | 0.144 | 1 (5) | 0.092 | 0 (0) | 0.433 | 2 (28.57) | 0.073 |
Moderate | 33 (48.53) | 10 (33.33) | 4 (20) | 6 (60) | 3 (42.86) | ||||
Massive | 1 (1.47) | 2 (6.67) | 1 (5) | 1 (10) | 0 (0) | ||||
Consolidation | 37 (54.41) | 20 (66.67) | 0.257 | 13 (65) | 0.401 | 7 (70) | 0.557 | 7 (100) | 0.054 |
Lobar or unilateral change | 34 (50) | 17 (56.67) | 0.721 | 11 (55) | 0.83 | 6 (60) | 0.513 | 6 (85.71) | 0.513 |
Bilateral pulmonary multiple change | 3 (4.41) | 3 (10) | 2 (10) | 1 (10) | 1 (14.29) | ||||
Pulmonary atelectasis | 7 (10.29) | 5 (16.67) | 0.581 | 5 (25) | 0.189 | 0 (0) | 0.586 | 2 (28.57) | 0.196 |
Liver dysfunction | 8 (11.76) | 4 (13.33) | 1 | 3 (15) | 1 | 1 (10) | 1 | 0 (0) | 1 |
Myocardial damage | 18 (26.47) | 7 (23.33) | 0.743 | 5 (25) | 0.895 | 2 (20) | 0.96 | 1 (14.29) | 0.803 |
Abnormal blood gas (hypoxemia, hypokalemia, etc.) | 2 (2.94) | 1 (3.33) | 1 | 0 (0) | 1 | 1 (10) | 0.341 | 2 (28.57) | 0.041 |
Central nervous system infection | 1 (1.47) | 1 (3.33) | 0.521 | 0 (0) | 1 | 1 (10) | 0.241 | 0 (0) | 1 |
Underlying conditions | |||||||||
Any condition (≥1 condition) | 8 (11.76) | 4 (13.33) | 1 | 3 (15) | 1 | 1 (10) | 1 | 1 (14.29) | 1 |
Respiratory disease (asthma, congenital malformation etc.) | 2 (2.94) | 2 (6.67) | 0.76 | 1 (5) | 0.543 | 1 (10) | 0.341 | 0 (0) | 1 |
Neurological Disease (epilepsy) | 2 (2.94) | 0 (0) | 1 | 0 (0) | 1 | 0 (0) | 1 | 0 (0) | 1 |
Congenital heart disease | 0 (0) | 2 (6.67) | 0.092 | 2 (10) | 0.05 | 0 (0) | – | 0 (0) | – |
Disease severity parameters | |||||||||
Severe CAPb | 49 (72.06) | 19 (63.33) | 0.388 | 10 (50) | 0.065 | 9 (90) | 0.409 | 6 (85.71) | 0.742 |
PICU admission | 0 (0) | 0 (0) | – | 0 (0) | – | 0 (0) | – | 0 (0) | – |
Noninvasive positive pressure ventilation | 4 (5.88) | 2 (6.67) | 1 | 1 (5) | 1 | 1 (10) | 0.506 | 0 (0) | 1 |
Invasive mechanical ventilation | 0 (0) | 0 (0) | – | 0 (0) | – | 0 (0) | – | 0 (0) | – |
Length of stay, median(IQR) (d) | 13 (5) | 14 (6) | 0.177 | 14.5 (6) | 0.163 | 13.5 (7) | 0.599 | 11 (3) | 0.319 |