Wheeze and Mycoplasma Pneumoniae

Association between inflammation factors and Mycoplasma pneumoniae in children: Protocol for a systematic review

BACKGROUND

Several clinical studies have reported that inflammation factors (IF) are associated with Mycoplasma pneumoniae in children. However, no study systematically investigated the association between IF and M pneumoniae in pediatric population. Thus, this study will explore the association between IF and pediatric M pneumoniae systematically.

METHODS

This study will search following databases of PUBMED, PsycINFO, Scopus, Cochrane Library, EMBASE, Web of Science, and Chinese Biomedical Literature Database from inception to the February 28, 2019 without any language limitations. We will cover clinical studies of M pneumoniae that report associations between IF and M pneumoniae. In addition, reference lists of relevant studies will also be identified to avoid missing any eligible studies. Two investigators will independently screen and select studies, and will assess the methodological quality for each study, which is evaluated by using Newcastle Ottawa Scale. Any disagreements will be settled down through discussion with a third investigator until consensus is reached.

RESULTS

This study will explore the associations between IF and M pneumoniae by assessing the changes of IF, such as interleukin (IL)-4, IL-5, IL-6, IL-10, IL-13, and IL-17 at different stages of M pneumoniae.

CONCLUSION

The findings of this study may provide most recent evidence for the associations between IF and M pneumoniae in pediatric populations.

ETHICS AND DISSEMINATION

Ethical approval is not needed in this study, because no individual patient data will be utilized in this study. The findings of this study are expected to be published at peer-reviewed journal or will be presented at professional conference.

PROSPERO REGISTRATION NUMBER

PROSPERO CRD42019125359.

Increased serum interleukin-5 and vascular endothelial growth factor in children with acute mycoplasma pneumonia and wheeze

Acute mycoplasma pneumonia may be accompanied by wheeze in some children considered not to have asthma. The aim of the present study was to evaluate cytokine secretion in children with acute mycoplasma pneumonia and wheeze. We studied 58 patients with mycoplasma pneumonia (12 with wheeze, Group 1; 46 without wheeze, Group 2) and 36 patients of non-mycoplasma pneumonia (Group 3). Serum levels of interleukin (IL)-4, IL-5, interferon (IFN)-gamma, and vascular endothelial growth factor (VEGF) were measured using an enzyme-linked immunosorbent assay kits. The mean +/- SD IL-5 level of Group 1 was 97.1 +/- 73.0 pg/ml, which was significantly higher than that of Group 2 (28.2 +/- 32.2 pg/ml) and that of Group 3 (35.7 +/- 42.0 pg/ml). The mean +/- SD VEGF level of Group 1 was 687.5 +/- 385.8 pg/ml, which was significantly higher than that of Group 2 (310.0 +/- 251.9 pg/ml) and that of Group 3 (402.3 +/- 279.5 pg/ml). No significant differences in serum levels of IL-4, IFN-gamma, and IgE were observed between the groups. Our results show that children with mycoplasma pneumonia and wheeze have significantly higher serum levels of IL-5 and VEGF. These increased immune responses may be associated with the pathophysiological mechanisms by which the Mycoplasma pneumoniae contribute to the development of wheeze during acute mycoplasma pneumonia.

Cytokines in Mycoplasma pneumoniae infections

Mycoplasma pneumoniae (M. pneumoniae) is one of the smallest free-living bacteria known. Along with other unique characteristics of this genus, it lacks the typical peptidoglycan cell wall of most eubacteria. Best known for causing tracheobronchitis and atypical pneumonia in humans, this pathogen also causes a number of extrapulmonary syndromes such as meningitis/encephalitis and arthritis. Recent studies also suggest that infection may be associated with chronic conditions such as asthma. Although the mechanisms of M. pneumoniae pathogenesis remain to be elucidated, one important component of M. pneumoniae infections is the induction of proinflammatory and other cytokines in both acute and chronic conditions. In this review, we survey the induction of cytokines by M. pneumoniae in different model systems, and we discuss the possible role of induced cytokines in M. pneumoniae pathogenesis.