Efficacy of glucocorticoids for the treatment of macrolide refractory mycoplasma pneumonia in children: meta-analysis of randomized controlled trials

Model based on the automated AI-driven CT quantification is effective for the diagnosis of refractory Mycoplasma pneumoniae pneumonia

The prediction of refractory Mycoplasma pneumoniae pneumonia (RMPP) remains a clinically significant challenge. This study aimed to develop an early predictive model utilizing artificial intelligence (AI)-derived quantitative assessment of lung lesion extent on initial computed tomography (CT) scans and clinical indicators for RMPP in pediatric inpatients. A retrospective cohort study was conducted on patients with M. pneumoniae pneumonia (MP) admitted to the Children's Hospital of Nanjing Medical University, China from January 2019 to December 2020. An early prediction model was developed by stratifying the patients with Mycoplasma pneumoniae pneumonia (MPP) into two cohorts according to the presence or absence of refractory pneumonia. A retrospective cohort of 126 children diagnosed with Mycoplasma pneumoniae pneumonia (MPP) was utilized as a training set, with 85 cases classified as RMPP. Subsequently, a prospective cohort comprising 54 MPP cases, including 37 instances of RMPP, was assembled as a validation set to assess the performance of the predictive model for RMPP from January to December 2021. We defined a constant Φ which can combine the volume and CT value of pulmonary lesions and be further used to calculate the logarithm of Φ to the base of 2 (Log2Φ). A clinical-imaging prediction model was then constructed utilizing Log2Φ and clinical characteristics. Performance was evaluated by the area under the receiver operating characteristic curve (AUC). The clinical model demonstrated AUC values of 0.810 and 0.782, while the imaging model showed AUC values of 0.764 and 0.769 in the training and test sets, respectively. The clinical-imaging model, incorporating Log2Φ, temperature(T), aspartate aminotransferase (AST), preadmission fever duration (PFD), and preadmission macrolides therapy duration (PMTD), achieved the highest AUC values of 0.897 and 0.895 in the training and test sets, respectively. A prognostic model developed through automated quantification of lung disease on CT scans, in conjunction with clinical data in MPP may be utilized for the early identification of RMPP.

The role of LDH and ferritin levels as biomarkers for corticosteroid dosage in children with refractory Mycoplasma pneumoniae pneumonia

BACKGROUND

This study explored the relationship between inflammatory markers and glucocorticoid dosage upon admission.

METHODS

We conducted a retrospective analysis of 206 patients with refractory Mycoplasma pneumoniae pneumonia (RMPP) admitted to a Children's Hospital from November 2017 to January 2022. Patients were categorized into three groups based on their methylprednisolone dosage: low-dose (≤ 2 mg/kg/d), medium-dose (2-10 mg/kg/d), and high-dose (≥ 10 mg/kg/d). We compared demographic data, clinical manifestations, laboratory findings, and radiological outcomes. Spearman's rank correlation coefficient was used to assess relationships between variables.

RESULTS

The median age was highest in the low-dose group at 7 years, compared to 5.5 years in the medium-dose group and 6 years in the high-dose group (P < 0.001). The body mass index (BMI) was also highest in the low-dose group at 16.12, followed by 14.86 in the medium-dose group and 14.58 in the high-dose group (P < 0.001). More severe radiographic findings, longer hospital stays, and greater incidence of hypoxia were noted in the high-dose group (P < 0.05). Additionally, significant increases in white blood cells, C-reactive protein, procalcitonin, lactate dehydrogenase (LDH), alanine transaminase, aspartate transaminase, ferritin, erythrocyte sedimentation rate, and D-dimer levels were observed in the high-dose group (P < 0.05). Specifically, LDH and ferritin were markedly higher in the high-dose group, with levels at 660.5 U/L and 475.05 ng/mL, respectively, compared to 450 U/L and 151.4 ng/mL in the medium-dose group, and 316.5 U/L and 120.5 ng/mL in the low-dose group. Correlation analysis indicated that LDH and ferritin levels were significantly and positively correlated with glucocorticoid dose (Spearman ρ = 0.672 and ρ = 0.654, respectively; P < 0.001).

CONCLUSIONS

Serum LDH and ferritin levels may be useful biomarkers for determining the appropriate corticosteroid dosage in treating children with RMPP.

Diagnostic value of serum CRP, PCT and IL-6 in children with nephrotic syndrome complicated by infection: a single center retrospective study

OBJECTIVE

The purpose was to look into the diagnostic value of serum CRP, PCT and IL-6 in children with nephrotic syndrome co-infection.

METHODS

One hundred and forty-nine children with nephrotic syndrome who met the inclusion and exclusion criteria were included in this study. The children were divided into three groups: bacterial infection group, non-bacterial infection group, and non-infection group. The diagnostic value was analyzed and compared using the ROC curve.

RESULTS

There was no statistically significant difference in the Leukocyte counts among three groups. The mean results of serum CRP, PCT and IL-6 were significantly higher in the bacterial infection group compared to those in the non-infection group (p < 0.05). AUC of CRP, PCT, IL-6 in bacterial infection were 0.791, 0.859, 0.783. The following combinations CRP + PCT + IL-6, IL-6 + PCT, CRP + PCT significantly increased the efficiency of bacterial infection diagnosis, the AUCs were 0.881, 0.884, and 0.884, respectively. AUC of PCT in non-bacterial infection was 0.663. The combinations of these three clinical indicators performed no better than PCT in ROC analysis.

CONCLUSION

Normal CRP or IL-6 levels do not rule out the diagnosis of bacterial infection in children on long-term glucocorticoid therapy. The appropriate combination of two or three indicators can improve the diagnostic value.

IMPACT

This study evaluated the diagnostic value of the serum concentrations of CRP, PCT and IL-6 and assessed whether the value of their combined application is better than when used alone for diagnosing primary nephrotic syndrome complicated by infection. The elevation in leukocyte count cannot be used to diagnose children with nephrotic syndromes on long-term glucocorticoid treatment who have bacterial infections. Normal CRP or IL-6 levels do not rule out the diagnosis of bacterial infection in children on long-term glucocorticoid therapy. The appropriate combination of two or three indicators can improve diagnostic value, sensitivity, and specificity.

Development and validation of a simple-to-use nomogram for predicting the delayed radiographic recovery in children with mycoplasma pneumoniae pneumonia complicated with atelectasis

This study aimed to develop and validate a simple-to-use nomogram for predicting the delayed radiographic recovery in children with mycoplasma pneumoniae pneumonia (MPP) complicated with atelectasis. A retrospective study of 306 children with MPP complicated with atelectasis was performed at the Children's Hospital of Chongqing Medical University from February 2017 to March 2020.The patients were divided into recovery group and delayed recovery group based on chest CT scan 1 month after discharge. A least absolute shrinkage and selection operator (LASSO) regression model was used to identify the optimal predictors, and the predictive nomogram was plotted by multivariable logistic regression. The nomogram was assessed by calibration, discrimination, and clinical utility. LASSO regression analysis identified that lactate dehydrogenase (LDH), duration of illness prior to bronchoalveolar lavage (BAL), systemic glucocorticoid use and extrapulmonary complications were the optimal predictors for delayed radiographic recovery. The nomogram was plotted by the four predictors. The area under the Receiver Operating Characteristic (ROC) curve of the nomogram was 0.840 (95% CI = 784 ∼ 0.896) in the training set and 0.833 (95% CI = 0.8737 ∼ 0.930) in the testing set. The calibration curve demonstrated that the nomogram was well-fitted, and decision curve analysis (DCA) showed that the nomogram was clinically beneficial. This study developed and validated a simple-to-use nomogram for predicting delayed radiographic recovery in children with MPP complicated with atelectasis. This might be generally applied in clinical practice.

Heart Failure Associated With Mycoplasma Pneumoniae Infection, A Case and Review of Literature

Mycoplasma pneumoniae is well known to cause pulmonary infection. However, it often has extrapulmonary manifestations as well. We diagnosed and treated a 41-year-old female who presented with symptoms of pneumonia along with multisystem involvement, including rash, acute hepatitis, and new onset heart failure that improved with steroids and doxycycline. Subsequent guideline-directed medical therapy for non-ischemic cardiomyopathy (NICM) coincided with the complete recovery of the left ventricular function in three months. We also did a brief literature review with similar prior reported cases.

Clinical Usefulness of Serum Lactate Dehydrogenase Levels in Mycoplasma pneumoniae Pneumonia in Children

OBJECTIVE

To elucidate the clinical usefulness of lactate dehydrogenase (LDH) levels in children with Mycoplasma pneumoniae (MP) pneumonia and identify cut-off levels in various clinical conditions.

METHODS

The study was retrospectively performed in 145 children who were hospitalized with MP pneumonia. Laboratory findings, including LDH levels at admission and clinical features were retrospectively reviewed from patients' electronic medical records.

RESULTS

The mean age of the study population was 5.9 y, and the mean value of LDH was 809.7 U/L. Poor response to treatment for MP pneumonia, respiratory virus coinfection, severe MP pneumonia, development of postinfectious bronchiolitis obliterans (PIBO) after MP pneumonia, pleural effusion, and oxygen need during illness were significantly associated with serum LDH levels. The cutoff levels of LDH for predicting poor response to treatment for MP pneumonia and respiratory virus coinfection were 1058 U/L [area under the curve (AUC), 0.729] and 803 U/L (AUC, 0.682), respectively. Those for pneumonic lesions involving at least one-third of the total lung volume, prediction of PIBO development, and extrapulmonary manifestations were 1098 U/L (AUC, 0.715), 676 U/L (AUC, 0.714), and 859 U/L (AUC, 0.710), respectively. The cutoff levels for pleural effusion during illness and for the prediction of oxygen need were 894 U/L (AUC, 0.699) and 1114 U/L (AUC, 0.771), respectively.

CONCLUSION

LDH levels are elevated in diverse clinical conditions in children with MP pneumonia and may be useful in the identification of severe clinical courses of MP pneumonia in children.

The efficacy and safety of minocycline as adjuvant therapy in refractory mycoplasma pneumonia in Chinese children: a meta-analysis

Background

To explore the efficacy and safety of minocycline as adjuvant therapy for refractory mycoplasma pneumonia in Chinese children.

Methods

PubMed, EMBASE, Cochrane Library, CNKI, Wanfang database and VIP database were systematically searched. Studies where minocycline was used as adjuvant therapy for refractory mycoplasma pneumonia in Chinese children were included. The effect of numeration data and the measurement data were represented by odds ratios (OR) and weighted mean differences (MD), respectively. Review Manager version 5.3 was used to compare the treatment efficacy, time for the cough to subside, defervescence time, hospitalisation time, adverse events and other indicators.

Results

Ten studies involving 857 patients were included in the final analysis. Compared with the conventional treatment of refractory mycoplasma pneumonia in children, the addition of minocycline as adjuvant therapy was found to improve the treatment efficacy (OR: 5.45; 95% CI: 3.46, 8.57, p < 0.001); shorten the duration of cough (MD: -3.61; 95%CI: -4.25, -2.97, p < 0.001), fever time (MD: -4.77; 95% CI: -6.30, -3.23, p < 0.001) and hospitalisation time (MD: -5.53 (95% CI: -7.19, -3.88, p < 0.001); and decrease the concentration of C-reactive protein (MD: -13.95; 95%CI: -18.61, -9.29; p < 0.001) and the erythrocyte sedimentation rate (MD: -10.88; 95% CI: -14.05, -7.72, p < 0.001). The use of minocycline did not lead to significant adverse events (OR = 0.63; 95% CI: 0.39, 1.01, p = 0.05).

Conclusion

The use of minocycline as adjuvant treatment of refractory mycoplasma pneumonia in Chinese children has good efficacy and safety and may be promoted in clinical practice.

The Effectiveness of Wogonin on Treating Cough Mice With Mycoplasma Pneumoniae Infection

Background: Cough is the main symptom of mycoplasma pneumoniae (MP) infection. Cough potential protein transient receptor potential A1 (TRPA1) plays an important role in cough reflex. The purpose of this study was to clarify the mechanism of wogonin, the effective component of Qinbai Qingfei concentrated pellet (Qinbai), in the treatment of cough after MP infection.

Methods: The Biacore™ system was used to detect whether there was specific binding between Qinbai and cough potential protein TRPA1. Biacore™ fishing technology and UPLC-Q-TOF-MS technology were used during fishing combined active components and identification and analysis of recovered samples. The expression levels of TRPA1, substance P (SP), calcitonin gene-related peptide (CGRP), cough-related proteins, and mRNA in the lung tissues from each group were detected by immunohistochemistry, Western blot, and real-time PCR.

Results: Biacore™ results showed that Qinbai had strong specific binding to TRPA1 protein with a binding value of 99.0 resonance unit (RU). The samples obtained from angling were identified and analyzed by UPLC-Q-TOF-MS as wogonin. The results of immunohistochemistry, Western blot, and real-time PCR showed that compared with the model group, the wogonin group had lower expressions of mRNA, TRPA1, SP, and CGRP in the lung tissue of cough mice with MP infection (p < 0.01 or p < 0.05), and the effects were superior to those of azithromycin and pentoxyverine control groups.

Conclusion: Wogonin can treat cough after MP infection by affecting the expressions of cough-related proteins, such as TRPA1, SP, and CGRP. This study provided a theoretical foundation for the clinical research of Qinbai.

Clinical significance of respiratory virus coinfection in children with Mycoplasma pneumoniae pneumonia

BACKGROUND

The prevalence of refractory Mycoplasma pneumoniae (MP) pneumonia has been increasing. However, few studies have investigated the impact of respiratory virus coinfection in patients with MP pneumonia, and their results have been inconclusive. This study aimed to investigate the impact of respiratory virus coinfection in children hospitalized with MP pneumonia.

METHODS

This study enrolled 145 children hospitalized with MP pneumonia between May 2019 and March 2020. The patients were divided into two groups: the respiratory virus coinfection and non-coinfection groups. All the children underwent polymerase chain reaction testing for respiratory virus infection. Information on clinical, laboratory, and radiologic findings were obtained retrospectively via medical chart reviews.

RESULTS

Children in the respiratory virus coinfection group were younger than those in the non-coinfection group. Respiratory virus coinfection in children hospitalized with MP pneumonia was significantly associated with persistence of fever more than 6 days (adjusted odds ratio [aOR], 2.394; 95% confidence interval [95% CI], 1.172-4.892), severe pneumonia (aOR, 4.602; 95% CI, 1.154-18.353), and poor response to the stepwise approach for MP pneumonia (aOR, 4.354; 95% CI, 1.374-13.800). In addition, higher levels of liver enzymes and lactate dehydrogenase at admission were associated with respiratory virus coinfection in children with MP pneumonia.

CONCLUSIONS

The results of this study suggest that respiratory virus coinfection in children hospitalized with MP pneumonia may be associated with refractory MP pneumonia.

Study on the Therapeutic Effect of Azithromycin Combined with Glucocorticoid on Pulmonary Function and Inflammatory Response in Children with Pneumonia

Objective

The objective is to explore the efficacy of azithromycin combined with glucocorticoids in the treatment of children with pneumonia and its effect on the inflammatory response.

Methods

A total of 86 children with pneumonia were divided into the experimental group (EG) and the control group (CG). Both groups received conventional treatment, the CG was treated with azithromycin and the EG was additionally treated with glucocorticoid methylprednisolone. The therapeutic effect, disappearance time of clinical symptoms, pulmonary function, inflammatory factors, immune function, quality of life, and adverse reactions were measured in the two groups.

Results

After treatment, compared with CG, the total effective rate was significantly elevated, the disappearance time of various clinical symptoms was earlier, and various pulmonary function indexes were increased in the EG. The interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C reactive protein (CRP), and CD8+ levels were reduced, and CD3+ and CD4+ levels were increased in the EG. The quality-of-life scores were upregulated in the EG. Moreover, there was no significant difference in the incidence of adverse reactions between the two groups.

Conclusion

The combined use of azithromycin and glucocorticoids in the treatment of children with Mycoplasma pneumoniae infection has a good curative effect, can significantly improve lung function, restore pulmonary inflammatory indexes to normal, and enhance patients' immune function and improve their quality of life, with fewer adverse reactions and safety.

Pseudomembranous necrotizing laryngotracheobronchitis due to Mycoplasma pneumoniae: a case report and literature review

Background

Pseudomembranous necrotizing laryngotracheobronchitis refers to an acute diffuse necrotizing inflammation in the mucosa of the larynx, trachea, and bronchus. It often occurs in infants and children having viral infections secondary to bacterial infections. Mycoplasma pneumoniae (M. pneumoniae) is a common pathogen that causes pneumonia in children. In recent years, serious complications due to M. pneumoniae infection, including necrotizing pneumonia, pulmonary embolism, and pleural effusion, have been increasingly reported.

Case presentation

An 11-year-old girl was admitted to our unit with cough, fever, and hoarseness persistent for a week. The results of the M. pneumoniae serological test, PCR examination with bronchial aspirate and bronchoalveolar lavage fluid (BALF), next-generation sequencing (mNGS) for BALF, all suggested the presence of M. pneumoniae infection. High-resolution CT scanning of the chest showed inflammation of the middle and lower lobes of the right lung. By bronchoscopy, the necrosis of the vocal cords, trachea, and bronchial mucosa was observed; each bronchial lumen contained a large amount of white viscous sputum. Pathological findings for bronchial mucosa suggested inflammatory necrosis. After administration of azithromycin and glucocorticoids, the symptoms of the patients were ameliorated. After 2 weeks post-discharge, the X-ray scan of her chest indicated the pneumonia resolution in the right lung.

Conclusions

In patients with pneumonia due to M. pneumoniae infection, which causes obvious hoarseness, bronchoscopy is necessary even if the lung lesions are not massively consolidated. When necrotizing lesions of the larynx, trachea, and bronchi are detected by bronchoscopy, the necrotic tissues in the corresponding parts should be conducted tissue biopsy for pathological examination. Apart from macrolide antibiotics, the administration of small doses of glucocorticoids is necessary.

Case Report and Literature Review: Clinical Characteristics of 10 Children With Mycoplasma pneumoniae-Induced Rash and Mucositis

Mycoplasma pneumoniae-induced rash and mucositis (MIRM) is a rare disease, which has not been reported in northern China previously. We retrospectively analyzed the clinical characteristics, diagnosis and treatment of 10 cases of MIRM in order to help clinicians to identify MIRM and to distinguish it from the similar mucositis and cutaneous characteristics of Stevens-Johnson syndrome. All 10 children included in the study had MIRM with skin and mucosal symptoms, but the characteristics of the skin and mucosal lesions differed by age. Most of the older children had sparse erythema and a vesicular rash, but the younger children had dense erythema without blisters but with purulent exudation. The mucositis was relatively mild in the younger children. The erythrocyte sedimentation rate, the levels of C-reactive protein, lactate dehydrogenase, and D-dimer were significantly elevated in most children with MIRM. Concomitant treatment of glucocorticoids and/or IVIG with macrolides may shorten the duration of fever and accelerate the clinical recovery. Additional case reports are needed to improve knowledge of the characteristics of MIRM and its response to therapy.

Chinese Herbal Medicine for the Treatment of Children and Adolescents With Refractory Mycoplasma Pneumoniae Pneumonia: A Systematic Review and a Meta-Analysis

Objectives: Chinese herb medicine (CHM) is one of the most popular complementary and alternative therapies, which has been widely used to treat Refractory Mycoplasma Pneumoniae Pneumonia (RMPP). However, the effect and safety of CHM remain controversial. Hence, we conducted this meta-analysis to evaluate whether CHM combination therapy could bring benefits to children and adolescents with RMPP. Methods: Seven databases were used for data searching through November 11, 2020 following the PRISMA checklist generally. Review Manager 5.3, Trial sequential analysis 0.9.5.10 Beta software and Stata16.0 were applied to perform data analyses. Mean difference or risk ratio was adopted to express the results, where a 95% confidence interval (CI) was applied. Results: In general, this research enrolled 17 trials with 1,451 participants. The overall pooled results indicated that CHM was beneficial for children and adolescents with RMPP by improving the clinical efficacy rate [RR = 1.20, 95% CI (1.15, 1.25), p < 0.00001], shortening antipyretic time [MD = -2.60, 95% CI (-3.06, -2.13), p < 0.00001], cough disappearance time [MD = -2.77, 95% CI (-3.12, -2.42), p < 0.00001], lung rale disappearance time [MD = -2.65, 95% CI (-3.15, -2.15), p < 0.00001], lung X-ray infiltrates disappearance time [MD = -2.75, 95% CI (-3.33, -2.17), p < 0.00001], reducing TNF-α level [MD = -5.49, 95% CI (-7.21, -3.77), p < 0.00001]. Moreover, subgroup results suggested that removing heat-phlegm and toxicity therapy had more advantages in shortening antipyretic time, cough disappearance time, lung X-ray infiltrates disappearance time and reducing TNF-α level. Meanwhile promoting blood circulation therapy seemed to be better at relieving lung rale. However, regarding adverse events, the two groups displayed no statistical difference [RR = 0.97, 95% CI (0.60, 1.57), p = 0.91]. Conclusion: Despite of the apparently positive results in relieving clinical symptoms, physical signs and reducing inflammation, it is premature to confirm the efficacy of CHM in treating RMPP because of the limitation of quality and the number of the included studies. More large-scale, double-blind, well-designed, randomized controlled trials are needed in future research.

Prediction model for prolonged fever in patients with Mycoplasma pneumoniae pneumonia: a retrospective study of 716 pediatric patients

Objective

To identify patients with Mycoplasma pneumoniae pneumonia (MPP) with a risk of prolonged fever while on macrolides.

Methods

A retrospective study was performed with 716 children admitted for MPP. Refractory MPP (RMPP-3) was defined as fever persisting for > 72 h without improvement in clinical and radiologic findings after macrolide antibiotics (RMPP-3) or when fever persisted for > 120 h (RMPP-5) without improvement in clinical and radiologic findings. Radiological data, laboratory data, and fever profiles were compared between the RMPP and non-RMPP groups. Fever profiles included the highest temperature, lowest temperature, and frequency of fever. Prediction models for RMPP were created using the logistic regression method and deep neural network. Their predictive values were compared using receiver operating characteristic curves.

Results

Overall, 716 patients were randomly divided into two groups: training and test cohorts for both RMPP-3 and RMPP-5. For the prediction of RMPP-3, a conventional logistic model with radiologic grouping showed increased sensitivity (63.3%) than the model using laboratory values. Adding laboratory values in the prediction model using radiologic grouping did not contribute to a meaningful increase in sensitivity (64.6%). For the prediction of RMPP-5, laboratory values or radiologic grouping showed lower sensitivities ranging from 12.9 to 16.1%. However, prediction models using predefined fever profiles showed significantly increased sensitivity for predicting RMPP-5, and neural network models using 12 sequential fever data showed a greatly increased sensitivity (64.5%).

Conclusion

RMPP-5 could not be effectively predicted using initial laboratory and radiologic data, which were previously reported to be predictive. Further studies using advanced mathematical models, based on large-sized easily accessible clinical data, are anticipated for predicting RMPP.

Characteristics and Outcome of Severe Mycoplasma pneumoniae Pneumonia Admitted to PICU in Shanghai: A Retrospective Cohort Study

Objectives:

We aimed to describe the characteristics and outcome in children with severe Mycoplasma pneumoniae pneumonia in a Chinese PICU.

Design:

A retrospective observational study from 2017 to 2019.

Setting:

A 36-bed university tertiary PICU at Shanghai Children’s Hospital.

Patients:

Patients admitted to a tertiary PICU 29 days to 18 years old screened for laboratory-confirmed severe M. pneumoniae pneumonia.

Interventions:

None.

Measurements and Main Results:

Descriptive analysis of baseline characteristics for patients included hospital mortality, organ dysfunctions, use of mechanical ventilation, continuous renal replacement therapy, and/or extracorporeal membrane oxygenation. A total of 817 children with severe pneumonia were admitted to PICU, and 203 of 817 cases (24.8%) with severe M. pneumoniae pneumonia were included in this study. The median age was 41 months (interquartile range, 20–67 mo), of which 77.3% (157/203) were younger than 6 years old. Among 163 patients with the test for macrolide resistance, 90.2% cases (147/163) were macrolide-resistant M. pneumoniae. Severe M. pneumoniae pneumonia-associated organ dysfunction included acute respiratory failure (203 cases, 100%), followed by cardiovascular disorder (79/203, 38.9%), gastrointestinal dysfunction (24/203, 11.8%). The main complications were pleural effusion (79/203, 38.9%), capillary leak syndrome (58/203, 28.6%), and plastic bronchitis (20/203, 9.9%). All patients needed respiratory support, including 64.5% patients (131/203) who received mechanical ventilation and 35.5% patients (72/203) who received high-flow nasal oxygen. Twenty-five patients (12.3%) treated with continuous renal replacement therapy and nine cases (4.4%) received extracorporeal membrane oxygenation. The case fatality rate was 3.9% (8/203). Furthermore, cardiovascular dysfunction, liver injury, or multiple organ dysfunction syndrome were associated with longer mechanical ventilation duration, delayed PICU discharge, and high hospital mortality. Coinfection was a risk factor of delayed PICU discharge.

Conclusions:

Children with severe M. pneumoniae pneumonia mainly occur under the age of 6 years, showing a high proportion of extrapulmonary organ dysfunction and macrolide resistances. Extrapulmonary organ dysfunction and coinfection are associated with worse outcomes. The overall mortality is relatively low after treated with appreciate antibiotics, respiratory support, and extracorporeal life support.

Predictive Factors of the Responses to Treatment of Mycoplasma pneumoniae Pneumonia

The prevalence of refractory Mycoplasma pneumoniae (MP) pneumonia is increasing. The present study aimed to identify the predictive factors of responses to treatment of MP pneumonia in children. A total of 149 children were diagnosed with MP pneumonia, of whom 56 were included in the good response group, 75 children in the slow response group, and 18 children in no response or progression group. Data on the clinical, laboratory, and radiologic features were retrospectively obtained through medical chart reviews. The severity of pneumonia, based on the extent of pneumonic lesions on chest x-ray (adjusted odds ratio (aOR), 10.573; 95% confidence intervals (CIs), 2.303-48.543), and lactate dehydrogenase (LDH) levels (aOR, 1.002; 95% CIs, 1.000-1.004) at the time of admission were associated with slow response to treatment of MP pneumonia. Pleural effusion (aOR, 5.127; 95% CIs, 1.404-18.727), respiratory virus co-infection (aOR, 4.354; 95% CIs, 1.374-13.800), and higher LDH levels (aOR, 1.005; 95% CIs, 1.002-1.007) as well as MP-specific IgM titer (aOR, 1.309; 95% CIs, 1.095-1.564) were associated with no response or progression of MP pneumonia. The area under the curve for the prediction of no or poor response in MP pneumonia using pleural effusion, respiratory virus co-infection, LDH levels, and MP-specific IgM titer at the time of admission was 0.8547. This study identified the predictive factors of responses to treatment of MP pneumonia in children, which would be helpful in establishing a therapeutic plan and predicting the clinical course of MP pneumonia in children.

Risk factors for the development of post-infectious bronchiolitis obliterans after Mycoplasma pneumoniae pneumonia in the era of increasing macrolide resistance

BACKGROUND

The prevalence of macrolide-resistant Mycoplasma pneumoniae (MP) pneumonia has been rapidly increased. MP pneumonia is a risk factor for the development of post-infectious bronchiolitis obliterans (PIBO). The aim of the present study was to identify the risk factors for the development of PIBO after MP pneumonia in the era of increasing macrolide resistance of MP.

MATERIALS AND METHODS

This retrospective study enrolled 150 children with a mean age of 6.0 years admitted to the hospital due to MP pneumonia between May 2019 and February 2020 at a tertiary hospital. The clinical, radiologic, and laboratory data were obtained using retrospective chart review.

RESULTS

Eighteen children (12%) were diagnosed with PIBO after MP pneumonia. PIBO was diagnosed after a mean duration of 100.0 days (range, 6-268 days) from symptom onset. The respiratory virus co-infection (adjusted odds ratio [aOR], 4.069; 95% confidence interval [95% CI], 1.224-13.523), adenovirus co-infection (aOR, 5.607; 95% CI, 1.801-17.454), longer duration between symptom onset and admission (aOR, 1.150; 95% CI, 1.020-1.298), higher levels of serum lactate dehydrogenase (LDH) at the time of admission (aOR, 1.001; 95% CI, 1.000-1.003), and poor response to stepwise treatment increased the risk for development of PIBO after MP pneumonia. However, macrolide resistance of MP was not associated with development of PIBO after MP pneumonia.

CONCLUSION

The present study suggests that respiratory virus co-infection, including adenovirus, poor response to the treatment of MP pneumonia, and higher levels of serum LDH, but not macrolide resistance of MP, are risk factors of PIBO after MP pneumonia.