传染病信息

目的 探讨血清γ干扰素（interferon γ, IFN-γ）、百日咳毒素（pertussis toxin, PT）IgG抗体（PT-IgG）与小儿百日咳严重程度的关系及对其并发支气管肺炎的预测效能。方法 选择宝鸡市妇幼保健院自2023年1月至2024年10月收治的398例百日咳患儿作为观察组，另选100例体检正常儿童作为对照组。依据严重程度将观察组患儿分为重症百日咳组（96例）、非重症百日咳组（302例）。检测所有入选者血清IFN-γ、PT-IgG水平，分析百日咳患儿血清IFN-γ、PT-IgG水平与白细胞介素（interleukin, IL）-17、IL-6、肿瘤坏死因子α(tumor necrosis factor-alpha, TNF-α)、白细胞（white blood cell,WBC）计数、淋巴细胞（lymphocyte, LYM）计数的关系；记录观察组患儿的支气管肺炎发生情况，依据是否并发支气管肺炎，分为支气管肺炎组（120例）与非支气管肺炎组（278例），比较支气管肺炎组与非支气管肺炎组血清IFN-γ、PT-IgG水平，使用试者工作特征（receiver operating characteristic, ROC）曲线分析血清IFN-γ联合PT-IgG对百日咳患儿发生支气管肺炎的预测效能。结果 观察组血清IFN-γ水平低于对照组，PT-IgG水平高于对照组（均P<0.05）；重症百日咳患儿血清IFN-γ水平低于非重症百日咳患儿，PT-IgG水平高于非重症百日咳患儿（均P<0.05）；支气管肺炎组血清IFN-γ水平低于非支气管肺炎组，PT-IgG水平高于非支气管肺炎组（均P<0.05）；经ROC曲线分析，血清IFN-γ联合PT-IgG预测百日咳患儿发生支气管肺炎的敏感度为93.47%、特异度为64.51%、ROC曲线下面积为0.915。经Pearson相关性分析，百日咳患儿血清IL-17、IL-6、TNF-α水平、WBC计数以及LYM计数与IFN-γ水平呈负相关（均P<0.05），与PT-IgG水平呈正相关（P<0.05）。结论 血清IFN-γ和PT-IgG不仅是百日咳严重程度的生物学指标，其联合检测对支气管肺炎的预测具有较高临床应用潜力。

Objective To investigate the associations of serum gamma-interferon(IFN-γ) and pertussis toxin antibody(PT-IgG) with disease severity in children with pertussis, and to evaluate their predictive value for the development of bronchopneumonia. Methods A total of 398 children with pertussis admitted to Baoji Maternal and Child Health Hospital between January 2023 and October 2024 were enrolled as the observation group, while 100 children with normal physical examination results were chosen as the control group. Based on disease severity, the observation group was further divided into a severe group(n=96) and a non-severe group(n=302). Serum IFN-γ and PT-IgG levels were tested in all participants. Their correlations with interleukin-17(IL-17), interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), white blood cell(WBC) count, and lymphocyte(LYM) count were analyzed. The occurrence of bronchopneumonia in the observation group was recorded, and patients were further categorized into a bronchopneumonia group(n=120) and a non-bronchopneumonia group(n=278). Differences in serum IFN-γ and PT-IgG levels between these groups were compared. Receiver operating characteristic curve(ROC) analysis was performed to assess the predictive efficacy of combined serum IFN-γand PT-IgG levels for the development of bronchopneumonia in children with pertussis. Results Compared with the control group, children with pertussis exhibited significantly lower serum IFN-γ levels and higher PT-IgG levels(P<0.05). Serum IFN-γ levels were significantly lower, whereas PT-IgG levels were significantly higher, in children with severe pertussis than in those with non-severe disease(P<0.05). Similarly, patients who developed bronchopneumonia had lower serum IFN-γ levels and higher PT-IgG levels compared with those without bronchopneumonia(P<0.05). ROC curve analysis showed that the combined measurement of serum IFN-γ and PT-IgG had a sensitivity of 93.47%, a specificity of 64.51%, and an area under curve(AUC) of 0.915 for predicting bronchopneumonia in children with pertussis. Pearson correlation analysis revealed that serum levels of IL-17, IL-6, TNF-α, WBC count, and LYM count were negatively correlated with IFN-γ levels(P<0.05) and positively correlated with PT-IgG levels(P<0.05). Conclusion Serum IFN-γand PT-IgG levels are not only biological indicators of pertussis severity, but their combined detection also has high potential for clinical application in predicting bronchopneumonia.