Thromboembolic complications of Mycoplasma pneumoniae pneumonia in children

The correlation between the level of cellular classification in bronchoalveolar lavage fluid of children with severe Mycoplasma pneumoniae and clinical characteristics

Mycoplasma pneumoniae pneumonia (MPP) is a common respiratory tract infection disease in children. To date, there have been few studies on the relationship between cytological changes in bronchoalveolar lavage fluid (BALF) and clinical features. The objective of this study is to investigate the correlation between changes in the proportion of cell classifications in BALF and the clinical features in children with severe MPP (SMPP). In total, the study included 64 children with SMPP requiring bronchoalveolar lavage who were admitted to our hospital between March and September 2022 (study group) and 11 children with bronchial foreign bodies without co-infection (control group), who were admitted during the same period. The proportion of cell classifications in BALF was determined by microscopic examination after performing Wright-Giemsa staining. Patients were grouped according to different clinical characteristics, and between-group comparisons were made regarding the variations in the proportion of cell classifications in BALF. The levels of blood routine neutrophil percentage (GRA%), C-reactive protein, D-dimer and lactate dehydrogenase in the study group were higher than those in the control group (P < 0.05). There were differences in the GRA% and macrophage percentage in the BALF between the two groups (P < 0.05). The GRA% and blood lymphocyte percentage were associated with pleural effusion. Multiple indicators correlated with extrapulmonary manifestations (P < 0.05). Moreover, the percentage of lymphocytes in the BALF correlated with pleural effusion, extrapulmonary manifestations and refractory MPP (RMPP) (P < 0.05). Logistic regression showed that BALF lymphocytes were protective factors for RMPP, while serum amyloid A and extrapulmonary manifestations were risk factors (P < 0.05).

CONCLUSION

The BALF of children with SMPP is predominantly neutrophilic. A lower percentage of lymphocytes is related to a higher incidence of pleural effusion, extrapulmonary manifestations and progression to RMPP, as well as a longer length of hospitalisation.

WHAT IS KNOWN

• Mycoplasma pneumonia in children is relatively common in clinical practice. Bronchoalveolar lavage (BAL) is a routine clinical procedure.

WHAT IS NEW

However, there are relatively few studies focusing on the cytomorphological analysis of cells in BAL fluid.

Mycoplasma pneumoniae pneumonia-associated thromboembolism with plastic bronchitis: a series of five case reports and literature review

BACKGROUND

Mycoplasma pneumoniae pneumonia is a common respiratory infection among children. However, the occurrence of thromboembolism with plastic bronchitis in association with Mycoplasma pneumoniae pneumonia is extremely rare. This case series presents five cases of children with Mycoplasma pneumoniae pneumonia who developed thromboembolism and plastic bronchitis. The clinical presentation, diagnostic approach, and management strategies are discussed.

METHODS

A retrospective analysis was conducted on medical records from a pediatric hospital. Patient demographics, clinical features, laboratory findings, imaging results, treatment modalities, and outcomes were collected.

RESULTS

The patients in our case series presented with varying degrees of respiratory distress, cough, and fever. Imaging studies revealed evidence of thromboembolism based on pulmonary artery occlusion. Bronchial casts were observed by bronchoscopy. Laboratory tests demonstrated elevated D-dimer levels and fibrinogen degradation products. All patients received a combination of low molecular weight heparin anticoagulation and supportive care.

CONCLUSION

Thromboembolism with plastic bronchitis associated with Mycoplasma pneumoniae pneumonia is a rare but potentially serious complication in children. Prompt recognition and management are crucial for improving patient outcomes. This case series highlights the diverse clinical presentations, diagnostic challenges, and treatment strategies for this unique clinical entity. Further research is needed to better understand the pathogenesis and optimal management of this condition.

Pulmonary Thrombotic Complication of Mycoplasma pneumoniae Pneumonia in Chinese Children: Clinical Feature and Risk Factor Analysis

BACKGROUND

Thrombotic disease is a rare but severe complication of Mycoplasma pneumoniae pneumonia in children, with pulmonary thrombosis (PT) being the most frequent type. This study aims to describe the clinical features of pediatric severe Mycoplasma pneumoniae pneumonia (SMPP) patients with PT, and to identify risk factors predictive of PT development in this population.

METHODS

We retrospectively enrolled 60 children with SMPP complicated by PT who were admitted to Children's Hospital Affiliated to Zhengzhou University from January 2019 to October 2023. We reviewed their demographic data, laboratory tests and imaging examinations to describe their clinical features. We used multivariate logistic regression analysis to identify significant risk factors for PT in SMPP.

RESULTS

The PT group exhibited higher incidences of chest pain, hemoptysis, inflammation and elevated D-dimer levels, as well as more severe pulmonary damage and transaminitis complication, compared to the non-PT group. The left pulmonary artery was the predominant location of PT in SMPP children. A multivariate analysis revealed that C-reactive protein (CRP) and D-dimer were significant predictors of PT in SMPP patients, with odds ratios of 1.10 and 3.37, respectively. The optimal cutoff values of CRP and D-dimer for predicting PT in SMPP were 76.73 mg/L and 3.98 µg/mL, respectively.

CONCLUSIONS

In SMPP, CRP >76.73 mg/L and D-dimer >3.98 µg/mL are independent predictors of PT. These findings suggest that SMPP-induced excessive inflammation may contribute to PT pathogenesis. Early and intensive anticoagulant, anti-inflammatory and antimycoplasma therapy may improve the disease course and prognosis.

Development and validation of an online dynamic nomogram system for pulmonary consolidation in children with Mycoplasma pneumoniae pneumonia

INTRODUCTION

The occurrence of pulmonary consolidation in children with Mycoplasma pneumoniae pneumonia (MPP) can lead to exacerbation of the disease. Therefore, early identification of children with MPP in combination with pulmonary consolidation is critical. The purpose of this study was to develop a straightforward, easy-to-use online dynamic nomogram for the identification of children with MPP who are at high risk of developing pulmonary consolidation.

METHODS

491 MPP patients were chosen and divided randomly into a training cohort and an internal validation cohort at a 4:1 ratio. Multi-factor logistic regression was used to identify the risk variables for mixed pulmonary consolidation in children with Mycoplasma pneumoniae (MP). The selected variables were utilized to build the nomograms and validated using the C-index, decision curve analysis, calibration curves, and receiver operating characteristic (ROC) curves.

RESULTS

Seven variables were included in the Nomogram model: age, fever duration, lymphocyte count, C-reactive protein (CRP), ferritin, T8 lymphocyte percentage, and T4 lymphocyte percentage. We created a dynamic nomogram that is accessible online ( https://ertong.shinyapps.io/DynNomapp/ ). The C-index was 0.90. The nomogram calibration curves in the training and validation cohorts were highly comparable to the standard curves. The area under the curve (AUC) of the prediction model was, respectively, 0.902 and 0.883 in the training cohort and validation cohort. The decision curve analysis (DCA) curve shows that the model has a significant clinical benefit.

CONCLUSIONS

We developed a dynamic online nomogram for predicting combined pulmonary consolidation in children with MP based on 7 variables for the first time. The predictive value and clinical benefit of the nomogram model were acceptable.

Marine-Derived Sulfated Glycans Inhibit the Interaction of Heparin with Adhesion Proteins of Mycoplasma pneumoniae

Mycoplasma pneumoniae, a notable pathogen behind respiratory infections, employs specialized proteins to adhere to the respiratory epithelium, an essential process for initiating infection. The role of glycosaminoglycans, especially heparan sulfate, is critical in facilitating pathogen-host interactions, presenting a strategic target for therapeutic intervention. In this study, we assembled a glycan library comprising heparin, its oligosaccharide derivatives, and a variety of marine-derived sulfated glycans to screen the potential inhibitors for the pathogen-host interactions. By using Surface Plasmon Resonance spectroscopy, we evaluated the library's efficacy in inhibiting the interaction between M. pneumoniae adhesion proteins and heparin. Our findings offer a promising avenue for developing novel therapeutic strategies against M. pneumoniae infections.