Objective: To explore the association between the levels of plasma D-dimer and the disease severity and prognosis of Mycoplasma pneumoniae pneumonia (MPP) in children.
Methods: We retrospectively analyzed the clinical data of pediatric MPP patients who were admitted in our hospital between January 1, 2016 and December 31, 2018. According to the peak value of D-dimer, patients were divided into the normal group (D-dimer<0.55 mg/L) and the elevated group (D-dimer≥0.55 mg/L). Information regarding the demographics, clinical manifestations, auxiliary examinations and treatments of patients in the two groups was compared.
Results: Of the 231 MPP patients included in the study, 70 were in the normal group and 161 were in the elevated group. The age of patients in the D-dimer elevated group was significantly higher than that of the normal group ( P<0.01). Compared with the normal group, the elevated group had longer lengths of fever, hospital stay and antibiotic therapy, and more severe radiographic manifestations (all P<0.01). In addition, the incidence of extrapulmonary complications, refractory MPP and severe MPP in the elevated group were significantly higher than those in the normal group ( P<0.01). As for the laboratory data, we found that neutrophils, C-reactive protein, lactate dehydrogenase, interleukin-6, interleukin-10 and interferon-γ were significantly higher in the elevated group than those in the normal group ( P<0.05). After treatments, all patients showed improvement and were discharged, but the proportions of patients requiring glucocorticoids, bronchoscopy, thoracentesis were significantly higher in the elevated group than those in the normal group ( P<0.05). Follow-up findings showed that the absorption rate of lung lesions 4 weeks after admission was significantly higher, the time needed for lung lesions absorption was significantly shorter, and the incidence of pulmonary sequelae was significantly lower in the normal group than those in the elevated group (all P<0.05). Correlation analysis showed that D-dimer level was positively correlated with the severity of pneumonia ( r=0.272, P=0.000) and the incidence of pulmonary sequelae ( r=0.235, P=0.000).
Conclusion: Pediatric patients of MPP who had elevated plasma D-dimer had clinical manifestations that were more severe, required longer duration of treatment and longer recovery time for lung lesions, and were more likely to have pulmonary sequelae.
目的: 探索血浆D-二聚体水平与儿童肺炎支原体肺炎（Mycoplasma pneumoniae pneumonia, MPP）疾病严重度及预后的相关性。
方法: 回顾性分析我院2016年1月–2018年12月收治的MPP患儿的临床资料，根据D-二聚体峰值分为正常组（D-二聚体<0.55 mg/L）和升高组（D-二聚体≥0.55 mg/L），比较两组患儿一般资料、临床表现、辅助检查及治疗情况。
结果: 入组的231例MPP患儿中，D-二聚体正常组70例，D-二聚体升高组161例。升高组患儿年龄大于正常组（P<0.01）。与D-二聚体正常组比较，升高组发热时间、住院时间、抗生素使用时间更长，影像学表现更重（P均<0.01）。同时升高组患儿肺外并发症、难治性MPP、重症MPP的发生率均高于正常组（P<0.01）。实验室检查发现，升高组患儿的中性粒细胞、超敏C反应蛋白、乳酸脱氢酶、白细胞介素6、白细胞介素10、γ干扰素均较正常组升高（P<0.05）。经治疗所有患儿均好转出院，但升高组使用激素、支气管镜、胸腔穿刺的比例均高于正常组（P<0.05）。入组患儿中有123例进行了长期随访，其中正常组43例，升高组80例。随访结果发现，正常组患儿入院后4周肺部病灶基本吸收比例高于升高组，肺部病灶吸收所需时间短于升高组，而出现肺部后遗症比例低于升高组（P均<0.05）。相关性分析显示D-二聚体水平与肺炎严重程度（r=0.272，P=0.000）、肺部后遗症（r=0.235，P=0.000）的发生呈正相关。
结论: 血浆D-二聚体升高的MPP患儿临床表现更重，治疗时间更长，肺部病灶恢复所需时间更久，更易出现肺部后遗症。
Keywords: Children; D-dimer; Mycoplasma pneumoniae; Pneumonia.
Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).