Increased Total Serum Immunoglobulin E in Children Developing Mycoplasma pneumoniae-related Extra-pulmonary Diseases

Abstract

Mycoplasma pneumoniae has been recognized to be involved in several extra-pulmonary diseases, but the underlying immunologic mechanisms are still largely unknown. Recently, we observed a significant elevation of serum Immunoglobulin E (IgE) in a small group of these children. Here, we assessed total serum IgE levels in children affected with Mycoplasma pneumoniae-related extra-pulmonary diseases.
 We prospectively collected the data of 162 children admitted to the hospital (because of respiratory infections or extra-pulmonary diseases) who were evaluated for Mycoplasma pneumoniae serology and total serum IgE levels, concomitantly. Based upon clinical and serology aspects, 3 groups of children were identified: I) with non-mycoplasma respiratory disease; II) with mycoplasma-related respiratory diseases; III) with extra-pulmonary diseases related to concomitant/recent Mycoplasma pneumoniae infection. Interestingly, children with Mycoplasma pneumoniae-related extra-pulmonary diseases showed a significant elevation of total serum IgE.
 In particular, patients developing Mycoplasma pneumoniae-related extra-pulmonary diseases (group III) showed significantly higher level of IgE than both previous groups (p<0.001 vs. group I; p<0.01 vs. group II).
 In conclusion, hospitalized children diagnosed with Mycoplasma pneumoniae-related extra-pulmonary diseases resulted to have significantly increased serum IgE compared to children developing respiratory illnesses only.

Impact of atopy on the severity and extrapulmonary manifestations of childhood Mycoplasmapneumoniae pneumonia

“…In addition, we found that the rate of atopy was higher in the patients with extrapulmonary manifestations than in those without extrapulmonary manifestations. Interestingly, the serum total IgE levels were also higher in the extrapulmonary group than in the pulmonary group, which was consistent with the findings in the recent reports . The increased IgE levels can be considered a marker of immune dysregulation .…”

“…Interestingly, the serum total IgE levels were also higher in the extrapulmonary group than in the pulmonary group, which was consistent with the findings in the recent reports. 7,8 The increased IgE levels can be considered a marker of immune dysregulation. 19,20 These findings may partly explain the relationship between atopy and extrarespiratory manifestations and indicate that an individual with an atopic predisposition could have an additional stimulation driving IgE production during MP infection;…”

“…Recently, Dimitri Poddighe et al observed an age‐dependent significant increase in the serum IgE levels in five children with different extrarespiratory complications of MP infection, indicating the condition of atopy. Moreover, they also confirmed this observation in a wider cohort of children; in the extrapulmonary disease group, the total serum IgE levels were significantly higher than those in children with classic respiratory infections due to MP . These observations suggest that atopy might be associated with MP‐related extrarespiratory manifestations; however, the influence of atopy on extrarespiratory complications of MP infection is largely unknown.…”

“…Moreover, they also confirmed this observation in a wider cohort of children; in the extrapulmonary disease group, the total serum IgE levels were significantly higher than those in children with classic respiratory infections due to MP. 8 These observations suggest that atopy might be associated with MP-related extrarespiratory manifestations; however, the influence of atopy on extrarespiratory complications of MP infection is largely unknown. Another study suggested that atopy may be a risk factor for the presence and severity of refractory MP pneumonia, 9 but no further data have been available to indicate the effect of atopy on the severity of MP pneumonia.…”

Chlamydia pneumoniae immunoglobulin E antibody levels in patients with asthma compared with non-asthma

“…Others have studied the immunologic response in respiratory infections caused by Mycoplasma pneumoniae (M. pneumoniae), which is an extracellular pathogen [10]. Increased total serum IgE levels were higher in hospitalized children diagnosed with different M. pneumoniae-related extra-pulmonary diseases compared with children that developed only classical respiratory illness due to M. pneumoniae [10]. The authors concluded that IgE probably had no role in the pathogenesis of these clinical manifestations, but the immune imprinting to produce IgE (i.e.…”