Table 1.
Demographic, Epidemiological, and Clinical Characteristics of Mycoplasma pneumoniae–Positive Community-acquired Pneumonia (CAP) Versus M. pneumoniae–Negative CAP in Children
| Characteristics | Mp-Positive CAPa (n = 29) | Mp-Negative CAPa (n = 34) | OR (95% CI) | P Value |
|---|---|---|---|---|
| Demographic characteristics | ||||
| Age, yb, median (IQR) | 8.6 (6.3–11.0) | 4.7 (3.9–6.2) | … | < .01 |
| Sex, male | 16 (55) | 23 (68) | 0.6 (.2–1.9) | .44 |
| Season at enrollment | ||||
| Spring (March–May) | 5 (17) | 6 (18) | 1.0 (.2–4.4) | 1.00 |
| Summer (June–August) | 9 (31) | 4 (12) | 3.3 (.8–16.8) | .07 |
| Autumn (September–November) | 9 (31) | 8 (23) | 1.5 (.4–5.2) | .58 |
| Winter (December–February) | 6 (21) | 16 (47) | 0.3 (.1–1.0) | .04 |
| Daycare or preschool attendance | 29 (100) | 34 (100) | NA | 1.00 |
| Immunizationsc | 21/23 (91) | 31/32 (97) | 0.3 (.0–7.0) | .57 |
| Underlying diseased | 1 (3) | 9 (26) | 0.1 (.0–.8) | .02 |
| Asthma or history of wheezing | 1 | 1 | … | |
| Cardiovascular | 0 | 0 | … | |
| Gastrointestinal | 0 | 2 | … | |
| Neurological | 0 | 2 | … | |
| Other | 0 | 4 | … | |
| Family with RTI | 17 (59) | 10 (29) | 3.3 (1.1–11.0) | .02 |
| Mothers | 14 | 4 | … | |
| Fathers | 6 | 1 | … | |
| Siblings | 17 | 7 | … | |
| Family members with Mp detection in URT | 17/47 (36) | 2/37 (5) | 9.7 (2.0–93.2) | < .01 |
| Mothers | 7/20 (35) | 2/26 (8) | 6.2 (1.0–69.7) | .03 |
| Fathers | 1/13 (8) | 0/10 (0) | NA | 1.00 |
| Siblings | 9/14 (64) | 0/1 (0) | NA | .40 |
| Symptomatic (RTI) | 10/17 (59) | 1/2 (50) | 1.4 (.0–123.1) | 1.00 |
| Asymptomatic (carrier) | 7/17 (41)e | 1/2 (50)e | 0.7 (.0–62.7) | 1.00 |
| Prior antibiotic treatment | 13 (45) | 5 (15) | 4.6 (1.3–19.6) | .01 |
| Clinical presentation | ||||
| Prodrome | ||||
| RTI symptoms, d, median (IQR) | 9.0 (6.0–10.0) | 4.0 (3.0–7.0) | … | < .01 |
| Fever, d, median (IQR) | 8.0 (6.0–10.0) | 4.0 (3.3–6.0) | … | < .01 |
| Fever >2 df | 26 (90) | 28 (82) | 1.8 (.3–12.5) | .49 |
| Fever, °C, at presentation, median (IQR) | 39.1 (39.0–39.7) | 39.2 (39.0–39.5) | … | .89 |
| RTI symptoms and signs at presentationg | ||||
| Runny nose | 7 (24) | 14 (41) | 0.5 (.1–1.5) | .19 |
| Sore throat | 4 (14) | 4 (12) | 1.2 (.2–7.1) | 1.00 |
| Cough | 27 (93) | 30 (88) | 1.8 (.2–21.2) | .68 |
| Chest pain | 3 (10) | 7 (21) | 0.5 (.1–2.2) | .32 |
| Wheezing | 0 (0) | 1 (3) | NA | 1.00 |
| Abnormal auscultatory findings | 19 (66) | 24 (71) | 0.8 (.2–2.6) | .79 |
| Oxygen saturation < 93% | 5 (17) | 8 (24) | 0.7 (.2–2.8) | .76 |
| Radiographic findings | ||||
| Pulmonary infiltrate in chest radiographh | 28/28 (100) | 31/32 (97) | NA | 1.00 |
| Consolidation | 18 (64) | 25 (78) | 0.5 (.1–1.8) | .26 |
| Single lobar infiltrate | 13 | 16 | … | |
| Multilobar infiltrates | 5 | 9 | … | |
| Multilobar infiltrates (unilateral) | 1 | 3 | … | |
| Multilobar infiltrates (bilateral) | 4 | 6 | … | |
| Interstitial | 10 (36) | 6 (19) | 2.4 (.6–9.5) | .16 |
| Reticular | 10 | 6 | … | |
| Nodular | 0 | 0 | … | |
| Pleural effusion | 4 (14) | 7 (22) | 0.6 (.1–2.7) | .52 |
| Severity of illness | ||||
| Hospitalization | 10 (34) | 19 (56) | 0.4 (.1–1.3) | .13 |
| LOS, d, median (IQR) | 4.5 (3.3–7.0) | 2.5 (2.0–5.8) | … | .31 |
| ICU admission | 0 (0) | 1 (3) | NA | 1.00 |
| Extrapulmonary manifestation | 9 (31)i | 0 (0) | NA | < .01 |
| Dermatological | 8 | … | … | |
| Neurological | 1 | … | … | |
| Treatment | ||||
| Antibiotics after enrollment | 27 (93)j | 31 (91)j | 1.3 (.1–16.7) | 1.00 |
| Amoxicillin ± clavulanic acid | 13 (45) | 29 (85) | 0.1 (.0–.5) | < .01 |
| Clarithromycin | 10 (34) | 1 (3) | 16.7 (2.1–772.7) | < .01 |
| Doxycycline | 10 (34) | 1 (3) | 16.7 (2.1–772.7) | < .01 |
| Other | 1 (3) | 2 (6) | 0.6 (.0–11.6) | 1.00 |
| Outcome | ||||
| Full recovery | 26 (90)k | 34 (100) | NA | .09 |
| Respiratory sequelae | 2 | … | … | |
| Dermatological sequelae | 1 | … | … |
Data are presented as no. or no. (%) unless otherwise indicated. Differences between groups were determined by the Mann-Whitney U test (medians) and Fisher exact test (proportions). P values <.05 are indicated in bold.
Abbreviations: CAP, community-acquired pneumonia; CI, confidence interval; ICU, intensive care unit; IQR, interquartile range; LOS, length of hospital stay; Mp, Mycoplasma pneumoniae; NA, not available; OR, odds ratio; RTI, respiratory tract infection; URT, upper respiratory tract.
aDefined according to the Mp-specific immunoglobulin M (IgM) antibody-secreting cell (ASC) enzyme-linked immunospot assay results [9].
bOnly patients between 3 and 18 years of age were enrolled (inclusion criteria) [9].
cPer the national immunization schedule in Switzerland.
dChronic lung disorders (excluding asthma) were part of the exclusion criteria [9].
eAsymptomatic carriers: Mp-positive CAP family members: 6 siblings, 1 mother; Mp-negative CAP family members: 1 mother.
fAccording to the prediction rule for risk of Mp infection in children with CAP by Fischer et al [23].
gInclusion criteria were clinical diagnosis of CAP with fever >38.5°C and tachypnea according to the British Thoracic Society guidelines [2].
hRadiographic evidence of pneumonia was not part of inclusion criteria, but routinely performed in 60 of 63 (95%) included CAP patients; 98% (59/60) met the criteria for radiological pneumonia [18, 19].
iDermatological (n = 8) [32]: Mp-induced rash and mucositis (n = 3), urticaria (n = 2), and maculopapular skin eruptions (n = 3); neurological (n = 1): aseptic meningitis.
jAntibiotic treatment with ≥1 agent: Mp-positive CAP: amoxicillin with or without clavulanic acid + clarithromycin (n = 4), amoxicillin with or without clavulanic acid + doxycycline (n = 3); Mp-negative CAP: amoxicillin + clarithromycin (n = 1), amoxicillin with or without clavulanic acid + ceftazidime (n = 1). Mp-positive CAP not treated with an antibiotic in vitro active against Mp: 9 (31%); all of them fully recovered.
kAbnormal outcomes: bronchiolitis obliterans with decreased lung function (n = 1), exertional dyspnea without physical findings, ie, normal lung and cardiac function (n = 1), postinflammatory pigmentary alteration (n = 1).