High Mycoplasma pneumoniae Loads and Persistent Long-term Mycoplasma pneumoniae DNA in Lower Airway Associated with Severity of Pediatric Mycoplasma pneumoniae Pneumonia

Abstract

Background: An increased number of refractory mycoplasma pneumoniae (MP) pneumonia (MPP) cases have been reported. However the duration of MP infection in lower airway and the course of anti-MP treatment remains unclear. Methods: We retrospectively reviewed the medical records of 94 MPP children. Patients were classified into two groups. The long-term group (Group LT) was defined as bronchoalveolar lavage fluid (BALF) remained MP-positive by PCR after 30 days of the disease course. The non-long-term group (Group NLT) was defined as BALF became MP-negative by PCR within 30 days of disease and patients who only needed one bronchoscopy lavage therapy. MP loads, clinical outcomes were analyzed along with other clinical measurements. Results: The average levels of inflammatory markers such as C reactive protein and lactate dehydrogenase in Group LT were significantly higher than those in Group NLT. Airway and lung damage in Group LT were more severe than Group NLT. 28 patients developed necrotizing pneumonia and 8 patients developed pulmonary embolism in Group LT. Mean maximum MP loads in BALF were 10 7.46±0.93 and 10 4.86±0.93 in Groups LT and NLT, respectively. There was persistent MP DNA in Group LT, even lasted for 120 days. One severe MPP patient in Group LT had MP-associated bloodstream infection. After 3 months of follow-up, chest imaging revealed incomplete absorption of pulmonary consolidation in 33 patients of Group LT [including 13 airway obliterans (AO) patients] and in 7 patients of Group NLT (including 2 AO patients). Conclusion: MP loads of BALF were associated with the subsequent duration of MP DNA in lower airway. High MP loads and persistent long-term MP DNA in lower airway were associated with severity of pediatric MPP.

Unresolved atelectasis in refractory Mycoplasma pneumoniae pneumonia: Predictive factors and the influence of corticosteroids and bronchoscopy lavage therapy

“…Yang et al reported corticosteroid therapy might prevent disease progression, and anti-MPantibiotics may have limited effects on MPP [1] . We agree with the above opinions that even timely macrolidesusceptible antibiotics such as moxi oxacin couldn't prevent disease progression through clinical experience [14] , so we didn't highly focus on the anti-MP treatment in this study.…”

“…To our knowledge, only a few studies mainly Chinese studies have reported of the effective and well-tolerated BLT and bronchoscopy ndings such as mucus plugs on the early stage of RMPP [14,17,[26][27][28] . It has been reported that airway hypersecretion, epithelial desquamation, and remodeling cause AO in a human airway epithelium model with M. pneumoniae infection [29] .…”

Proteomic Study of Mycoplasma Pneumoniae Pneumonia Reveals FCGBP as A Serum Biomarker and Implicates Potential Therapeutic Targets

“…Corticosteroid could effectively initiate the rapid improvement of clinical symptoms and chest radiographic findings, however its resistant has been reported in some RMPP patients with more severe presentations and more serious radiological finding 8 . In the near ten years, RMPP and SMPP are very common in North China particularly in our hospital, which have much higher sequelae rate mainly BO 2,[4][5][6] . Thus, there is an urgent need to discover serum biomarkers and target drugs for monitoring the progress and prevent airway remodeling of SMPP.…”

“…The clinical presentation of mycoplasma pneumoniae (MP) pneumonia (MPP) includes pulmonary symptoms like bronchiolitis and pneumonia even necrotizing pneumonia, thrombosis, and the extra-pulmonary symptoms such as encephalitis, and hemolytic anemia. Persistent MP infection, airway obstruction and airway remodeling have been concerned in human airway epithelium, BALB/c mice, and SMPP children [1][2][3] . MPP patients may develop into severe life-threatening pneumonia (severe MPP, SMPP) with features of respiratory failure and acute respiratory distress syndrome, and sequelae such as atelectasis and bronchiectasis due to bronchiolitis/bronchitis obliterans (BO) resulting from airway remodeling 2,[4][5][6][7] .…”

Proteomics study of Mycoplasma pneumoniae pneumonia reveals the Fc fragment of the IgG-binding protein as a serum biomarker and implicates potential therapeutic targets

“…The clinical presentation of Mycoplasma pneumoniae (MP) pneumonia (MPP) includes pulmonary symptoms, such as bronchiolitis, pneumonia or necrotizing pneumonia, thrombosis, and extrapulmonary symptoms, such as encephalitis and hemolytic anemia. Persistent MP infection, airway obstruction, and airway remodeling have been reported in the airway epithelium of BALB/c mice and children with severe MPP (SMPP) [1][2][3]. Patients with MPP may develop life-threatening SMPP with respiratory failure, acute respiratory distress syndrome, and sequelae such as atelectasis and bronchiectasis caused by bronchiolitis/bronchitis obliterans (BO), which results from airway remodeling [2,[4][5][6][7].…”