Mycoplasma pneumoniae pneumonia with pulmonary embolism: A study on pediatric cases in Jilin province of China

Abstract

Mycoplasma is one of the most common pathogens causing community-acquired pneumonia in pediatric patients. In recent years, the number of refractory or severe cases with drug resistance has been gradually increasing and cases that developed embolism after Mycoplasma pneumoniae (M. pneumoniae) infection have been reported. The present study retrospectively analyzed the clinical features, diagnosis and treatment of M. pneumoniae pneumonia (MPP) combined with pulmonary embolism (PE) in a series of 7 cases encountered between January 1st, 2016 to August 1st, 2019 at the Department of Pediatric Intensive Care Unit of The First Hospital of Jilin University (Changchun, China). Combined with relevant Chinese and international studies published during the last two decades, a comprehensive analysis was performed. All of the pediatric patients of the present study had fever, cough and dyspnea respiratory symptoms at onset and the disease progressed rapidly. Thereafter, PE was confirmed by a series of examinations. Pulmonary CT indicated patchy inflammations and significantly elevated D-dimer levels, accompanied by positive anticardiolipin antibodies. Furthermore, a filling defect in the pulmonary artery branch was observed on CT pulmonary angiography (CTPA) examination. In 2 cases, the condition was improved with anti-infection and anticoagulation treatment with low-molecular-weight heparin and warfarin, respectively, and the pulmonary embolism disappeared after 3-4 months. A total of 5 cases, who were not responsive to the drug treatment, underwent surgical resection. During the operation, the local tissues were determined to be infarcted and the pathological diagnosis was consistent with pulmonary infarction. Among the 5 cases, 2 died of Acute Respiratory Distress Syndrome at 3-8 days after the operation. The remaining patients underwent 6-12 months of follow-up and respiratory rehabilitation and their quality of life is now good. In conclusion, compared with healthy individuals, pediatric patients with critical MPP have an elevated risk of embolism. It is necessary to be vigilant regarding whether MMP is combined with PE and perform timely CTPA examination. Early detection, early treatment and surgical intervention (if necessary) may significantly reduce the risk of mortality and disability.

Keywords: computed tomographic pulmonary angiography; mycoplasma pneumonia; pediatric patients; pulmonary embolism; refractory mycoplasma pneumonia.

Figure 1

Bilateral pulmonary extensive diffuse inflammation, with bilateral atelectasis of the dorsal lobes of a 7 year old male.

Figure 2

Bilateral pulmonary extensive diffuse inflammation with consolidation in the right lung of an 8 year old male.

Figure 3

Severe inflammatory changes in the bilateral lungs with extensive subcutaneous emphysema of an 11 year old male.

Figure 4

Inflammation in the middle lobe of the right lung and all lobes of the left lung of a 6 year old female, with partial atelectasis in the lower lobe of the left lung (upper panel) and mild pericardial effusion (lower panel).

Figure 5

Bilateral pulmonary arterial filling defect of a 6 year old male; arterial embolism is visible in multiple branches, with mild dilation of the pulmonary trunk (white arrows; scale bar, 5 cm).

Figure 6

Histological image displaying pulmonary infarction and necrosis with abscess formation in an 8 year old female (H&E staining; scale bar, 200 µm).

Figure 7

Extensive infarction and necrosis of the resected pulmonary tissues with infiltration of a large amount of inflammatory cells in an 11 year old female (H&E staining; scale bar, 100 µm).