Consideration in treatment decisions for refractory Mycoplasma pneumoniae pneumonia

Age-related effects of Mycoplasma pneumoniae infection and subsequent asthma exacerbation in children

BACKGROUND

Mycoplasma pneumoniae causes community-acquired pneumonia in children and increases asthma risk, but large studies are lacking.

OBJECTIVE

To assess the link between M. pneumoniae infection and to asthma exacerbation, in children with allergies, and age of infection impact.

METHODS

This retrospective cohort study analyzed medical records of South Korean children between January 2002 and December 2017. The study's exposure was hospitalization with an M. pneumoniae-related diagnosis, and the outcome was defined as asthma exacerbation, confirmed by hospitalization at least 6 months after M. pneumoniae infection, with alternative validation using asthma diagnosis and systemic steroid prescription records. Hazard ratios (HRs) for asthma exacerbation risk were estimated for the matched cohort using a Cox proportional hazards model stratified by allergic comorbidities. Time-dependent covariates and age-stratified exposure groups were used to calculate odds ratios.

RESULTS

The study included 84,074 children with M. pneumoniae infection and 336,296 unexposed children. Follow-up for 12.2 ± 2.3 years found the exposed group had a significant risk of asthma exacerbation (HR 2.86, 95% confidence interval [CI] 2.67-3.06) regardless of allergic comorbidities. The risk was highest (over threefold) in children infected between 24 and 71 months. Sensitivity analysis using an alternative definition of the outcome showed an HR of 1.38 (95% CI 1.35-1.42), further supporting the association between M. pneumoniae infection and asthma exacerbation.

CONCLUSION

M. pneumoniae infection was significantly associated with an increased risk of subsequent asthma exacerbation regardless of allergic comorbidities. Further research needed for understanding and confirmation.

Investigating the occurrence of autoimmune diseases among children and adolescents hospitalized for Mycoplasma pneumoniae infections

Background

Mycoplasma pneumoniae infection is common in the general population and may be followed by immune dysfunction, but links with subsequent autoimmune disease remain inconclusive.

Objective

To estimate the association of M. pneumoniae infection with the risk of subsequent autoimmune disease.

Methods

This retrospective cohort study examined the medical records of South Korean children from 01/01/2002 to 31/12/2017. The exposed cohort was identified as patients hospitalized for M. pneumoniae infection. Each exposed patient was matched with unexposed controls based on birth year and sex at a 1:10 ratio using incidence density sampling calculations. The outcome was subsequent diagnosis of autoimmune disease, and hazard ratios (HRs) were estimated with control for confounders. Further estimation was performed using hospital-based databases which were converted to a common data model (CDM) to allow comparisons of the different databases.

Results

The exposed cohort consisted of 49,937 children and the matched unexposed of 499,370 children. The median age at diagnosis of M. pneumoniae infection was 4 years (interquartile range, 2.5-6.5 years). During a mean follow-up time of 9.0 ± 3.8 years, the incidence rate of autoimmune diseases was 66.5 per 10,000 person-years (95% CI: 64.3-68.8) in the exposed cohort and 52.3 per 10,000 person-years (95% CI: 51.7-52.9) in the unexposed cohort, corresponding to an absolute rate of difference of 14.3 per 10,000 person-years (95% CI: 11.9-16.6). Children in the exposed cohort had an increased risk of autoimmune disease (HR: 1.26; 95% CI: 1.21-1.31), and this association was similar in the separate analysis of hospital databases (HR: 1.25; 95% CI 1.06-1.49).

Conclusion

M. pneumoniae infection requiring hospitalization may be associated with an increase in subsequent diagnoses of autoimmune diseases.

The analysis of risk factors for recurrent wheezing in infants and clinical intervention

Background

Asthma is one of the most common chronic diseases affecting children's health, and recurrent wheezing in infants is closely related to childhood asthma. However, up to now, there is a lack of unified diagnostic criteria and interventions for recurrent wheezing in infants. By analyzing and discussing the risk factors of recurrent wheezing in infants and related intervention measures, we aim to take individualized treatment for different children and reduce the occurrence of recurrent wheezing in infants.

Methods

From January 2017 to December 2020, children under 3 years old who were admitted to the Department of Pediatric Respiratory of Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine with the chief complaint of wheezing for the first time and were clinically diagnosed with bronchiolitis, asthmatic bronchopneumonia and asthmatic bronchitis were retrospectively analyzed through telephone questionnaires. These children were divided into two groups based on whether the wheezing occurred again after discharge. The demographic characteristics, clinical treatment, imaging characteristics, and related interventions and outcomes after discharge were analyzed in both groups.

Results

Among the 523 children under 3 years old who were hospitalized due to wheezing, 264 (50.5%) did not have wheezing after discharge, and 259 (49.5%) still had wheezing after discharge. Both chi-squared test and multivariate analysis showed that male, history of eczema, history of rhinitis, history of wheezing before hospitalization, family smoke exposure, mycoplasma infection and inhalation allergen sensitization were risk factors for recurrent wheezing in infants and young children (P<0.05). Simultaneously, Cox survival curve showed that different intervention time and intervention methods would lead to different prognosis.

Conclusions

(I) Male, with a history of eczema, rhinitis, wheezing before hospitalization, family environment smoke exposure, mycoplasma infection and a history of inhalation allergy are high risk factors for recurrent wheezing in the recurrent wheezing group, and are more likely to have recurrent wheezing after discharge, with shorter days of wheezing control; (II) there was a significant interaction between mycoplasma infection and a history of inhalation allergy in infants with the risk of recurrent wheezing; (III) long-term intervention for children with wheezing for 4 weeks or more after discharge can reduce the probability of recurrent wheezing; (IV) for children of male, with a history of eczema or rhinitis, the most effective intervention to reduce the probability of recurrent wheezing is long-term inhaled corticosteroids (ICS) treatment after discharge.

The molecular characteristics, diagnosis, and treatment of macrolide-resistant Mycoplasma pneumoniae in children

The purpose of this study is to review the molecular characteristics, the diagnosis, and treatment of the widespread infection of macrolide-resistant Mycoplasma pneumoniae (M. pneumoniae; MRMP) in children, thus providing a better knowledge of this infection and presenting the associated problems. Single point mutations in the V region of the 23S rRNA gene of M. pneumoniae genome are associated with macrolide resistance. P1-1, MLVA4-5-7-2, and ST3 are usually the predominated genetic types in the M. pneumoniae epidemics. The short-term two times serological IgM (or together with IgG) test in the acute stage can be used for confirmation. Combined serological testing and PCR might be a more prudent method to reduce macrolide consumption and antibiotic selective pressure in a clinical setting. Molecular methods for the detection of single-nucleotide mutations in the V region of the 23S rRNA gene can be used for the diagnosis of MRMP. The routine use of macrolide for the treatment of macrolide-sensitive Mycoplasma pneumoniae (MSMP) infections can get good effect, but the effects are limited for severe MRMP infections. Additional corticosteroids may be required for the treatment of severe MRMP infections in children in China during the era of MRMP.

Efficacy of Gamma Globulin Combined with Azithromycin Sequential Therapy in the Treatment of RMPP and Its Effect on Th1/Th2 Cytokine Levels

Objective

To investigate the efficacy of gamma globulin combined with azithromycin sequential therapy in the treatment of children with refractory mycoplasma pneumonia and its effect on Th1/Th2 cytokine levels.

Method

From January 2021 to January 2022, 100 children diagnosed with refractory mycoplasma pneumonia were randomly divided into 2 groups (50 cases in each one), the control group was treated with azithromycin plus comprehensive basic treatment, and the treatment group was treated with combined treatment on the basis of the control group, gamma globulin therapy; the treatment effect and cytokine levels of the two groups were compared.

Results

Th1, Th2, and Th1/Th2 before treatment were not significantly different between the two groups. Th1, Th2, and Th1/Th2 in the treatment group were significantly downregulated compared with those in the control group after treatment. The levels of IgG, IgA, and IgM in the treatment group were not significantly different from those in the control group before treatment but were significantly upregulated after treatment. IL-10, IL-6, and IL-2 levels were also significantly increased in the treatment group. The disappearance time of clinical symptoms such as fever, cough, and pulmonary rales in the treatment group was significantly shorter than that in the control group, and the cure rate in the treatment group was significantly better than that in the control group.

Conclusion

The clinical effect of gamma globulin combined with azithromycin sequential therapy in the treatment of children with refractory mycoplasma pneumonia is remarkable, which can reduce inflammatory factors, improve patients' immunity, and promote disease recovery.

[Value of autotaxin in predicting refractory Mycoplasma pneumoniae pneumonia in children and its correlation with inflammatory cytokines]

OBJECTIVES

To study the value of autotaxin (an autocrine motility factor) level in serum and bronchoalveolar lavage fluid (BALF) in predicting refractory Mycoplasma pneumoniae pneumonia (RMPP) in children and its correlation with interleukin-6 (IL-6), interleukin-8 (IL-8), and C-reactive protein (CRP).

METHODS

A retrospective analysis was performed on 238 children with Mycoplasma pneumoniae pneumonia who were admitted from January 2019 to December 2021. According to disease severity, they were divided into two groups: RMPP (n=82) and general Mycoplasma pneumoniae pneumonia (GMPP; n=156). The two groups were compared in terms of the levels of autotaxin, IL-6, IL-8, and CRP in serum and BALF to study the value of autotaxin level in serum and BALF in predicting RMPP in children, as well as the correlation of autotaxin level with IL-6, IL-8, and CRP in children with RMPP.

RESULTS

Compared with the GMPP group, the RMPP group had significantly higher levels of autotaxin, IL-6, IL-8, and CRP in serum and BALF (P<0.05). For the children with RMPP, the levels of autotaxin, IL-6, IL-8, and CRP in serum and BALF in the acute stage were significantly higher than those in the convalescent stage (P<0.05). The receiver operating characteristic (ROC) curve showed that the level of autotaxin in serum and BALF had a good value in predicting RMPP in children, with an area under the curve of 0.874 (95%CI: 0.816-0.935) and 0.862 (95%CI: 0.802-0.924), respectively. The correlation analysis showed that the level of autotaxin in serum and BALF was positively correlated with IL-6, IL-8, and CRP levels (P<0.001).

CONCLUSIONS

The level of autotaxin in serum and BALF increases and is correlated with the degree of disease recovery and inflammatory cytokines in children with RMPP. Autotaxin can be used as a predictive indicator for RMPP in children.

A prediction study of IL-18 and IFN-γ in glucocorticoid treatment response in infants and young children with severe Mycoplasma pneumoniae pneumonia

BACKGROUND

In infants and young children, the clinical decision to apply glucocorticoids to severe Mycoplasma pneumoniae pneumonia (SMPP) is more an empirical choice with reference to clinical symptoms, but the effect is not satisfying. We aimed to explore and identify early predictive indicators of ideal response to glucocorticoids treatment in SMPP in infants and young children.

METHODS

We retrospectively reviewed the data of 59 patients, which met the age range and diagnostic criteria, admitted to Department of Pediatrics, the Sixth People's Hospital Affiliated to Shanghai Jiaotong University, from January to December 2017. Patients were divided into a glucocorticoid treatment group and a normal treatment group according to whether glucocorticoid treatment was used, and the difference in therapeutic effectiveness was compared between two groups. The glucocorticoid treatment group was further subdivided into effective versus ineffective treatment groups dependent on the difference of glucocorticoid treatment effect in main clinical symptoms improvement. We obtained the test value of biomarkers by ELISA, and identified several specific indicators with significantly different expressions in the early stage by independent sample t-tests and calculated their cut-off values by ROC curve.

RESULTS

Thirty-one SMPP patients who received glucocorticoid treatment were divided into effective and ineffective treatment groups according to the clinical improvements shown on different days of glucocorticoid use. The expression of two markers, interleukin-18 (IL-18) and interferon-γ (IFN-γ), were significantly different in cases showing improvement in the early stage of SMPP (P<0.05), and the cut-off values for IL-18 (218.19 pg/mL, AUC =0.581, sensitivity =0.909, 1-specificity =0.786) and IFN-γ (11.24 pg/mL, AUC =0.566, sensitivity =0.905, 1-specificity =0.795) were identified.

CONCLUSIONS

The expressions of IL-18 and IFN-γ in the early stage of SMPP might suggest their predictive effect of early application of glucocorticoid for effective treatment of SMPP in infants and young children. Further study with larger sample size will be carried on in the future.

Association of children wheezing diseases with meteorological and environmental factors in Suzhou, China

Wheezing diseases are one of the major chronic respiratory diseases in children. To explore the effects of meteorological and environmental factors on the prevalence of children wheezing diseases, clinical data of children hospitalized with wheezing diseases in Suzhou, China from 2013 to 2017 were collected. Meteorological and environmental factors from 2013 to 2017 were obtained from the local Meteorological Bureau and Environmental Protection Bureau. Relationships between wheezing diseases and meteorological and environmental factors were evaluated using Pearson's correlation and multivariate regression analysis. An autoregressive integrated moving average (ARIMA) model was used to estimate the effects of meteorological and environmental variables on children wheezing diseases. Children wheezing diseases were frequently presented in infants less than 12 months old (1897/2655, 58.28%), and the hospitalization rate was highest in winter (1024/3255, 31.46%). In pathogen-positive specimens, the top three pathogens were respiratory syncytial virus (21.35%), human rhinovirus (16.28%) and mycoplasma pneumoniae (10.47%). The seasonality of wheezing children number showed a distinctive winter peak. Children wheezing diseases were negatively correlated with average temperature (P < 0.001, r =  - 0.598). The ARIMA (1,0,0)(0,0,0)₁₂ model could be used to predict temperature changes associated wheezing diseases. Meteorological and environmental factors were associated with the number of hospitalized children with wheezing diseases and can be used as early warning indicators for the occurrence of wheezing diseases and prevalence of virus.

Clinical Characteristics of Macrolide-Refractory Mycoplasma pneumoniae Pneumonia in Korean Children: A Multicenter Retrospective Study

Mycoplasma pneumoniae is a major causative pathogen of community-acquired pneumonia in children, and the treatment of choice is macrolides. There is an increasing trend in reports of refractory clinical responses despite macrolide treatment due to the emergence of macrolide-resistant M. pneumoniae. Early discrimination of macrolide-refractory M. pneumoniae pneumonia (MrMP) from macrolide-sensitive M. pneumoniae pneumonia (MSMP) is vital; however, testing for macrolide susceptibility at the time of admission is not feasible. This study aimed to identify the characteristics of MrMP in Korean children, in comparison with those of MSMP. In this multicenter study, board-certified pediatric pulmonologists at 22 tertiary hospitals reviewed the medical records from 2010 to 2015 of 5294 children who were hospitalized with M. pneumoniae pneumonia and administered macrolides as the initial treatment. One-way analysis of variance and the Kruskal-Wallis test were used to compare differences between groups. Of 5294 patients (mean age, 5.6 years) included in this analysis, 240 (4.5%), 925 (17.5%), and 4129 (78.0%) had MrMP, macrolide-less effective M. pneumoniae pneumonia, and MSMP, respectively. Compared with the MSMP group, the MrMP group had a longer fever duration, overall (13.0 days) and after macrolide use (8.0 days). A higher proportion of MrMP patients had respiratory distress, pleural effusion, and lobar pneumonia. The mean aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and C-reactive protein levels were the highest in the MrMP group, along with higher incidences of extrapulmonary manifestations and atelectasis (during and post infection). Pre-existing conditions were present in 17.4% (n = 725/4159) of patients, with asthma being the most common (n = 334/4811, 6.9%). This study verified that MrMP patients show more severe initial radiographic findings and clinical courses than MSMP patients. MrMP should be promptly managed by agents other than macrolides.