Associations of radiological features in Mycoplasma pneumoniae pneumonia

Multidimensional analysis using low-dose computed tomography to evaluate the severity of Mycoplasma pneumoniae pneumonia in children

Background

It is unclear whether local pathological pulmonary changes truly reflect the severity of childhood Mycoplasma pneumoniae infection, which is characterized by rapid progress and potential mortality. This study multi-dimensionally analyzed low-dose computed tomography findings to assess the severity of Mycoplasma pneumoniae infection and predict its progress in such patients.

Methods

In all, 752 children with Mycoplasma pneumoniae pneumonia (MPP) who underwent low-dose computed tomography examinations from February 2016 to July 2020 were retrospectively enrolled to conduct a cohort study. Clinical and radiological variables were analyzed using univariate analysis, and radiological variables were further analyzed using multivariable logistic regression in severe cases. Then, the correlation between the key computed tomography features and clinical symptoms, laboratory indicators, and medical costs were assessed using the chi-squared and Kruskal-Wallis H tests. Kaplan-Meier curves and Cox regression models were created to evaluate the correlations between the key computed tomography features, fever duration, and the length of hospital stay.

Results

Of the 752 included patients, 16.2% (122/752) developed severe MPP. Atelectasis, pleural effusion, and lung consolidation occurred in 9.7% (73/752), 15.8% (119/752), and 90.3% (679/752) of patients, respectively. In addition to pleural effusion, the number of lobes of lung consolidation was the highest risk feature of severe MPP. Patients with consolidation in 2, 3, and 4 lobes had a 1.0-, 3.1-, and 7.5-fold increased risk of severe MPP, compared with patients with consolidation in fewer than 1 lobe. The duration of fever prior to admission had no effect on the proportions of the lobar consolidation (P=0.14) but did have significant effect on the incidence of pleural effusion (P=0.004). Levels of inflammatory markers and medical costs rose consistently with the increase in the number of lobar consolidations (P<0.001). After adjustments for pleural effusion, 1, 2, 3, and 4 lobes of consolidation remained positively associated with fever duration [1 lobe: hazard ratio (HR) =1.55, 95% CI: 1.10-2.18; 2 lobes: HR =1.65, 95% CI: 1.13-2.42l; 3 lobes: HR =1.82, 95% CI: 1.11-2.98; 4 lobes: HR =2.87, 95% CI: 1.25-6.61] compared to 0 lobes of consolidation. Compared to 0 lobes of consolidation, 1, 2, 3, and 4 lobes of consolidation were also positively correlated with the length of hospital stay (1 lobe: HR =2.24, 95% CI: 1.73-2.89; 2 lobes: HR =2.56, 95% CI: 1.91-3.43; 3 lobes: HR =2.87, 95% CI: 1.90-4.32; 4 lobes: HR =4.12, 95% CI: 2.01-8.46).

Conclusions

Lobar consolidation is a stable and reliable computed tomography feature that can be used to assess the severity of MPP in children. Quantitative analysis of lobar consolidation can comprehensively and accurately predict the progression of Mycoplasma pneumoniae. Low-dose computed tomography is recommended for children with severe MPP with complicated courses.

The diagnostic value of serological tests and real-time polymerase chain reaction in children with acute Mycoplasma pneumoniae infection

Background

This study set out to evaluate the clinical significance and diagnostic effectiveness of serological tests and real-time polymerase chain reactions (RT-PCR) in children of different age groups and disease durations infected with Mycoplasma pneumoniae (MP).

Methods

Pediatric patients with lower respiratory tract infection (LRTI) confirmed by polymerase chain reaction (PCR) were enrolled and subjected to bronchoalveolar lavage fluid PCR (BALF-PCR) for MP infection. The diagnostic values of the serum immunoglobulin M (IgM) test, paired sera immunoglobulin G (IgG) test, RT PCR applied to nasopharyngeal aspirates (NPA-PCR), and combined IgM and NPA-PCR test were evaluated.

Results

When BALF PCR was used as the gold standard, the MP positivity rate of combined IgM and NPA PCR was 78.85%in children aged 3–5 years. The positivity rates of IgM, NPA PCR, and combined IgM and NPA PCR in children older than 5 years were 71.21%, 72.72%, and 84.85%, respectively. The detection rate of combined IgM and NPA PCR was consistent with BALF PCR (Kappa =0.727). The MP positivity rates of combined IgM and NPA PCR at 1–2 weeks was as high as 91.11%, and was consistent with the BALF PCR (Kappa =0.756). Moreover, the positivity rates of IgM or NPA PCR at 2-3 weeks were 63.16%, and were consistent with each other (Kappa =0.771).

Conclusions

Combined IgM and NPA PCR is the optimal test to confirm MP infection among children aged 3–5 years in cases with a disease duration of less than2 weeks, and either NPA PCR or IgM is recommended for children older than 5 years with a disease duration of 2–3 weeks.

Keywords

Mycoplasma pneumoniae pneumonia (MPP); diagnosis; children; age; disease duration

Severe atypical pneumonia in critically ill patients: a retrospective multicenter study

BACKGROUND

Chlamydophila pneumoniae (CP) and Mycoplasma pneumoniae (MP) patients could require intensive care unit (ICU) admission for acute respiratory failure.

METHODS

Adults admitted between 2000 and 2015 to 20 French ICUs with proven atypical pneumonia were retrospectively described. Patients with MP were compared to Streptococcus pneumoniae (SP) pneumonia patients admitted to ICUs.

RESULTS

A total of 104 patients were included, 71 men and 33 women, with a median age of 56 [44-67] years. MP was the causative agent for 76 (73%) patients and CP for 28 (27%) patients. Co-infection was documented for 18 patients (viruses for 8 [47%] patients). Median number of involved quadrants on chest X-ray was 2 [1-4], with alveolar opacities (n = 61, 75%), interstitial opacities (n = 32, 40%). Extra-pulmonary manifestations were present in 34 (33%) patients. Mechanical ventilation was required for 75 (72%) patients and vasopressors for 41 (39%) patients. ICU length of stay was 16.5 [9.5-30.5] days, and 11 (11%) patients died in the ICU. Compared with SP patients, MP patients had more extensive interstitial pneumonia, fewer pleural effusion, and a lower mortality rate [6 (8%) vs. 17 (22%), p = 0.013]. According MCA analysis, some characteristics at admission could discriminate MP and SP. MP was more often associated with hemolytic anemia, abdominal manifestations, and extensive chest radiograph abnormalities. SP-P was associated with shock, confusion, focal crackles, and focal consolidation.

CONCLUSION

In this descriptive study of atypical bacterial pneumonia requiring ICU admission, mortality was 11%. The comparison with SP pneumonia identified clinical, laboratory, and radiographic features that may suggest MP or CP pneumonia.

Clinical characteristics of pneumonia caused by Mycoplasma pneumoniae in children of different ages

To study clinical characteristics of Mycoplasma pneumoniae pneumonia (MPP) in children of different ages. We investigated the medical records of MPP patients admitted at Children's Hospital of Soochow University from January 2006 and December 2013. The presence of MP was confirmed by real-time PCR and ELISA. There were overall 3358 children with MPP. 412 (12.3%) were <6 months old. Six months to 1 year, 1-3 years, 3-5 years and ≥5 years old children constituted 423 (12.6%), 1033 (30.8%), 733 (21.8%) and 757 (22.5%) respectively. Fever was less frequent in <6 months old infants, with frequency increasing in older patients. The proportion of patients with wheeze was highest (57.9%) in patients aged 6 months to 1-year-old. Tachypnea, cyanosis and hypoxemia were more prevalent in <6 months old infants (P=0.00). Radiologically, bronchopneumonia was frequent among infants, while segmental/lobar pneumonia was frequent in ≥5 years old patients. White blood cell and platelet counts of infants were significantly higher than other children. Neutrophil count, c-reaction protein levels was significantly different amongst age groups. Our study revealed MPP patients of different ages presented with different clinical findings especially <6 months old and ≥5 years of age, which may indicate different pathological findings in age groups of patients with MPP.

Mycoplasma pneumoniae 23S rRNA A2063G mutation does not influence chest radiography features in children with pneumonia

Objective

To measure the rate of the A2063G mutation in the Mycoplasma pneumoniae (M. pneumoniae) 23S rRNA domain V in children with pneumonia and to determine the correlation between radiographic findings and the presence of the A2063G mutation.

Methods

Patients who were hospitalized with a confirmed diagnosis of M. pneumoniae pneumonia were enrolled in this study. M. pneumoniae strains were collected for genotype analysis. Chest radiography was performed on all children prior to and following macrolide treatment. Clinical and imaging data were obtained.

Results

Of 211 patients, 195 (92.42%) harboured M. pneumoniae with the A2063G mutation. No significant differences were identified in inflammation score, chest radiography inflammation absorption grade before and after macrolide treatment, or pulmonary complications (atelectasis, hydrothorax, or pleuritis) prior to macrolide treatment when children were stratified based on the presence or absence of the A2063G mutation.

Conclusions

A high proportion of children with pneumonia harboured strains of M. pneumoniae with the A2063G mutation in the 23S rRNA domain V. However, no obvious chest radiographic features of M. pneumoniae pneumonia were associated with the A2063G variant.

[Association of T lymphocyte subsets and allergens with Mycoplasma pneumoniae infection complicated by wheezing in infants and young children]

OBJECTIVE

To investigate the percentage of T lymphocyte subsets and allergen screening results in infants and young children with Mycoplasma pneumoniae (MP) infection complicated by wheezing.

METHODS

Flow cytometry was used to measure the percentage of peripheral blood T cell subsets in 354 infants and young children with MP infection complicated by wheezing (MP wheezing group), 336 infants and young children with MP infection but without wheezing (MP non-wheezing group), and 277 children with recurrent wheezing (recurrent wheezing group). Allergen screening was also performed for these children.

RESULTS

Both the MP wheezing group and recurrent wheezing group had significantly lower percentages of CD3⁺ and CD3⁺CD8⁺ lymphocytes than the MP non-wheezing group (p<0.05). The MP groups with or without wheezing had a significantly higher percentage of CD3⁺CD4⁺ lymphocytes than the recurrent wheezing group (p<0.05). Both the MP wheezing group and recurrent wheezing group had significantly higher percentages of CD3^-CD19⁺ and CD19⁺CD23⁺ lymphocytes than the MP non-wheezing group (p<0.05), and the recurrent wheezing group had the highest percentages (p<0.05). The overall positive rate of food allergens was significantly higher than that of inhaled allergens (30.3% vs 14.7%; p<0.05). The positive rates of food and inhaled allergens in the recurrent wheezing group and MP wheezing group were significantly higher than in the MP non-wheezing group (p<0.05), and the recurrent wheezing group had the highest rates.

CONCLUSIONS

Imbalance of T lymphocyte subsets and allergic constitution play important roles in the pathogenesis of MP infection complicated by wheezing in infants and young children.

A preliminary study on the potential of Mycoplasma pneumoniae to induce dyskaryotic change in respiratory epithelium in adult community-acquired pneumonia

Background:

This study aimed to explore the cellular morphology of respiratory epithelium in Mycoplasma pneumonia (MpP) patients.

Materials and Methods:

The cast-off cell morphological findings from bronchoscopic brushings in MpP and community-acquired pneumonia (CAP) caused by typical pathogens were reviewed.

Results:

Compared with the CAP group, cellular dysplasia in respiratory tract epithelial brushings was significantly greater in MpP patients (P = 0.033).

Conclusion:

Unique biological characteristics and mechanisms of pathogenesis of Mycoplasma pneumoniae (Mp) may result in dyskaryotic changes in respiratory epithelium in adult MpP.

Community-Acquired Pneumonia Caused by Mycoplasma pneumoniae: How Physical and Radiological Examination Contribute to Successful Diagnosis

Mycoplasma pneumoniae is one of the most common causes of community-acquired pneumonia (CAP), particularly in young adults. Vital signs are usually normal except for temperature. On physical examination, general appearance is normal compared with that of typical pneumonia such as pneumococcal pneumonia patients. Mycoplasma sometimes causes ear infections such as otitis media. It is important to distinguish between typical pneumonia and atypical pneumonia such as mycoplasma pneumonia because having the right diagnosis allows for the use of the correct antibiotic to treat CAP while preventing development of drug-resistant bacteria and also decreasing medical cost. The symptoms and diagnosis of mycoplasma pneumonia is multi-fold. Auscultation of patients can demonstrate trace late inspiratory crackles or normal alveolar sounds; however, bilateral polyphonic wheezes can sometimes be heard because of bronchiolitis. With regard to radiological findings, a chest radiogragh often shows bilateral reticulonodular or patchy consolidation in both lower lobes. Pleural effusion is rarely observed in adult cases. Immunocompetent patients tend to reveal more extensive shadowing compared with immunocompromised patients. As serological diagnostic methods are not able to offer 100% reliable diagnosis, integration of physical and radiological examination is crucial to accurately diagnose mycoplasma pneumonia. Herein, I review the typical findings from physical examination and imaging patterns of patients with mycoplasma pneumonia.