Infection with Mycoplasma pneumoniae is not related to asthma control, asthma severity, and location of airway obstruction

Protective effect of inhaled corticosteroid on children with asthma with Mycoplasma pneumoniae pneumonia

BACKGROUND

The aim of this study was to determine the differences in the characteristics of Mycoplasma pneumoniae pneumonia (MPP) in children with and without asthma and in children with asthma with and without inhaled corticosteroid (ICS) therapy in order to determine the risk factors for asthma exacerbation and the effect of regular ICS therapy on children with asthma with MPP.

MATERIALS AND METHODS

Children with MPP were divided into two groups according to whether they had a history of asthma. Children with asthma were further divided into an ICS therapy group and a group without ICS therapy. The clinical characteristics, laboratory test results, and pulmonary images were compared between the children with and without asthma. Differences in the severity of acute exacerbation were compared between the children with asthma in the ICS therapy and without ICS therapy groups. Multivariable logistic regression was used to determine the risk factors for exacerbation of MPP in children with asthma.

RESULTS

In children with MPP, the differences in the eosinophil counts; total immunoglobulin E (IgE), C-reactive protein, procalcitonin (PCT), and lactate dehydrogenase (LDH) levels; and fever duration, wheezing, extrapulmonary complications, oxygen saturation < 92%, severe pneumonia, pleural effusion, co-infection with other pathogens, and lobar pneumonia between children with and without asthma were statistically significant. Among children with asthma with MPP, those in the ICS therapy group were less likely to experience an exacerbation, and exacerbations were less severe than those in the without ICS therapy group. The multivariable logistic regression analysis showed that the ICS therapy was an independent protective factor against exacerbation.

CONCLUSION

Among children with MPP, the chance of wheezing was higher in children with asthma than in children without asthma. The ICS therapy was a protective factor against exacerbation in children with asthma with MPP.

Chronic infection with Chlamydia pneumoniae in asthma: a type-2 low infection related phenotype

Background

Chlamydia pneumoniae and Mycoplasma pneumoniae have been implicated in the pathogenesis of asthma and are responsible for chronic inflammation when host immune system fails to eradicate the bacteria.

Method

We performed a prospective study on 410 patients who underwent a visit at the asthma clinic of CHU of Liege between June 2016 and June 2018 with serology testing for C. pneumoniae and M. pneumoniae.

Results

65% of our asthmatic population had serum IgA and/or IgG towards C. pneumoniae, while only 12.6% had IgM and/or IgG against M. pneumoniae. Compared to seronegative asthmatics, asthmatics with IgA+ and IgG+ against C. pneumoniae were more often male and older with a higher proportion of patients with smoking history. They received higher doses of inhaled corticosteroids (ICS) and displayed lower FEV₁/FVC ratio, higher RV/TLC ratio and lower conductance. They had higher levels of fibrinogen, though in the normal range and had lower sputum eosinophil counts. Patients with IgA− and IgG+ against C. pneumoniae were older and had higher blood monocyte counts and alpha-1-antitrypsin levels as compared to seronegative patients. Patients with IgM and/or IgG towards M. pneumoniae were more often males than seronegative asthmatics. In a subpopulation of 14 neutrophilic asthmatics with Chlamydia pneumoniae IgA + /IgG + treated with macrolides, we found a significant decrease in blood neutrophils and normalization of sputum neutrophil count but no effect on asthma quality of life and exacerbations.

Conclusion

Positive Chlamydia serologic test is more common than positive Mycoplasma serology. Asthmatics with IgA and IgG against C. pneumoniae have more severe disease with increased airway obstruction, higher doses of ICS, more signs of air trapping and less type-2 inflammation.

Epidemiological relationship between Mycoplasma pneumoniae pneumonia and recurrent wheezing episode in children: an observational study at a single hospital in Korea

OBJECTIVE

This study was aimed to evaluate epidemiological and clinical relationship between Mycoplasma pneumoniae (MP) infection and childhood recurrent wheezing episode (RWE).

DESIGN

Retrospective case note review.

SETTING

Paediatric department at a single Korean institution.

PARTICIPANTS

Consecutive admitted patients with MP pneumonia and RWE (0-15 years of age) between 2003 and 2014.

METHODS

The retrospective medical records of patients with (MP) pneumonia (n=793 for epidemiological analysis and n=501 for clinical analysis) and those with RWE (n=384) from 2003 to 2014 were analysed. Diagnosis of MP pneumonia was made based on two-times titration of IgM antibody during hospitalisation. An RWE patient was defined as one with expiratory wheezing with at least one or more wheezing episodes based on medical records.

RESULTS

During three MP pneumonia epidemics, there were no corresponding increases of patients with RWE in the epidemic years. In the 501 MP pneumonia patients, 52 (10.4%) had wheezing at presentation and 15 (3%) had RWE. The MP pneumonia patients with wheezing at presentation (n=52) were younger and were more likely to have an allergic disease history than those without wheezing (n=449). Among wheezing patients at presentation, 10 patients had previously RWE history. In a follow-up study, 13 patients (including 5 RWE) with initial wheezing and 25 patients (including 2 RWE) without wheezing had wheezy episodes after discharge. Among the total 501 patients, it was estimated that at least 31 MP pneumonia patients (6.2%) showed recurrent wheezing after initial MP infection.

CONCLUSIONS

A small part of children with MP pneumonia showed recurrent wheezing after MP pneumonia, and patients with RWE had a greater likelihood of experiencing wheezing when they had an initial MP infection. However, there were no increased admitted patients with RWE in MP pneumonia epidemic periods because of rarity of MP reinfection in children including patients with RWE or asthma.

Mycoplasma pneumonia infection and asthma: A clinical study

OBJECTIVES

To evaluate the correlation between mycoplasma pneumonia infection and the severity of asthma as well as asthma control, to help physicians in respiratory department better make treatment strategies.

METHODS

Since January 2012 to May 2014, we consecutively recruited 149 out-patients diagnosed with asthma in acute or convalescent phase from the department of respiratory medicine of our hospital. The pulmonary function tests, sputum induction examination, measurement of IgM, IgG and IgE in serum, evaluation of asthma control were carried out for all the included patients.

RESULTS

In 78 cases with asthma in acute phase, mycoplasma pneumonia infection was confirmed in 38 cases (48.71%), and in 71 cases in stable state, mycoplasma pneumonia infection was confirmed in 22 cases (30.98%). There was significant difference in the rate of mycoplasma pneumonia infection between the two groups (p<0.05). The FEV1% Pred and ACT scores were significantly lower in mycoplasma pneumonia infection cases than those in no mycoplasma pneumonia infection cases (p<0.05), while the eosinophil count and IgE in serum were significantly higher in mycoplasma pneumonia infection cases (p<0.05).

CONCLUSIONS

Mycoplasma pneumonia infection may play more important role in the occurrence of acute asthma, and it can lead to decreased pulmonary function, difficulty in controlling asthma and more severe airway inflammation.

Physiological measurement of the small airways

Noninvasive physiological measurements are reviewed that have been reported in the literature with the specific aim being to study the small airways in lung disease. This has mostly involved at-the-mouth noninvasive measurement of flow, pressure or inert gas concentration, with the intent of deriving one or more indices that are representative of small airway structure and function. While these measurements have remained relatively low-tech, the effort and sophistication increasingly reside with the interpretation of such indices. When aspiring to derive information at the mouth about structural and mechanical processes occurring several airway generations away in a complex cyclically changing cul-de-sac structure, conceptual or semi-quantitative lung models can be valuable. Two assumptions that are central to small airway structure-function measurement are that of an average airway change at a given peripheral lung generation and of a parallel heterogeneity in airway changes. While these are complementary pieces of information, they can affect certain small airways tests in confounding ways. We critically analyzed the various small airway tests under review, while contending that negative outcomes of these tests are probably a true reflection of the fact that no change occurred in the small airways. Utmost care has been taken to not favor one technique over another, given that most current small airways tests still have room for improvement in terms of rendering their content more specific to the small airways. One way to achieve this could consist of the coupling of signals collected at the mouth to spatial information gathered from imaging in the same patient.