分析不同年龄段百日咳患儿的临床特征。

回顾性分析2022年1月至2024年12月成都市公共卫生临床医疗中心确诊的567例百日咳患儿临床资料，根据年龄分为≤3月龄组（118）、3～36月龄组（180例）、36月龄～6岁组（115例）和＞6岁组（154例）。收集患儿一般资料、疫苗接种史、流行病学特征、临床症状及实验室指标[白细胞（WBC）计数、淋巴细胞绝对值（ALC）和血小板（PLT）计数]，多组间比较采用卡方检验或Kruskal-Wallis H检验。

567例患儿中36月龄～6岁和＞6岁组患儿发病比例较高，分别为20.3%（115/567）和27.2%（154/567）；全年均可发病，以夏季（61.2%、347/567）高发，春季（22.4%、127/567）次之；未接种疫苗和未完全免疫患儿共262例（46.2%）。患儿主要临床症状有阵发性痉挛性咳嗽（84.7%、480/567）、呕吐（35.8%、203/567）和鸡鸣样吼声（29.6%、168/567）；各年龄段百日咳患儿阵发性痉挛性咳嗽（χ²=38.36、P＜0.001）、鸡鸣样吼声（χ²=47.44、P＜0.001）和湿啰音或喘鸣音（χ²=92.22、P＜0.001）和肺炎（χ²=47.49、P＜0.001）发生率差异有统计学意义，且随患儿年龄增长而递减，其中≤3月龄组与3～36月龄组患儿以上临床表现发生率均显著高于＞6岁组（P均＜0.001）。WBC计数（H=68.65、P＜0.001）、ALC（H=163.25、P＜0.001）和PLT计数（H=190.72、P＜0.001）差异均有统计学意义，其中≤3月龄组和3～36月龄组患儿以上指标均显著高于36月龄～6岁组和＞6岁组，差异均有统计学意义（P均＜0.001）。

低龄儿童百日咳临床症状典型，以≤3月龄患儿尤为明显；WBC、ALC和PLT在低龄患儿中普遍升高，结合患儿临床表现对百日咳的早期识别具有一定参考价值。

To investigate the clinical characteristics of pediatric patients with pertussis across different age groups.

Clinical data of 567 pediatric patients with pertussis diagnosed at Chengdu Public Health Clinical Medical Center from January 2022 to December 2024 were analyzed, retrospectively. Patients were grouped into≤3 months group (118 cases), 3-36 months group (180 cases), 36 months-6 years old group (115 cases) and>6 years old group (154 cases). General information, vaccination history, epidemiological characteristics, clinical manifestations, and laboratory test results [white blood cell (WBC) count, absolute lymphocyte count (ALC) and platelet (PLT) count] were collected, respectively. Intergroup comparisons were performed by Chi-square test or Kruskal-Wallis H test.

Among the 567 enrolled children, the incidence rates were higher in 36 month-6 years old [20.3% (115/567)] and>6 years old groups [27.2% (154/567)] , respectively; Cases occurred throughout the year, with a peak incidence in summer (61.2%, 347/567), followed by spring (22.4%, 127/567); while 262 children (46.2%) were unvaccinated or not fully immunized. The main clinical symptoms included paroxysmal spasmodic cough (84.7%, 480/567), vomiting (35.8%, 203/567) and crowing-like stridor (29.6%, 168/567). The incidence of paroxysmal spasmodic cough (χ²=38.36, P<0.001), crowing stridor (χ²=47.44, P<0.001), wet rales or wheezing (χ²=92.22, P<0.001) and pneumonia (χ²=47.49, P<0.001) were significantly different among children with pertussis of all age groups; moreover, the incidence decreases with age increasing in pediatric patients, both≤3 month old group and 3-36 month old group exhibiting significantly higher rates of these clinical manifestations compared with>6 years old group (all P<0.001). White blood cell (WBC) count (H=68.65, P<0.001), absolute lymphocyte count (ALC) (H=163.25, P<0.001) and platelet (PLT) count (H=190.72, P<0.001) were significantly different among children with pertussis of all age groups; the above mentioned indicators were significantly higher in≤3 month old group and 3-36 month-old group compared with 36 month to 6 years old group and>6 years old group, all with significant differences (all P<0.001).

Clinical manifestations of pertussis in young children are typical, particularly evident in infants aged≤3 months. WBC, ALC and PLT levels are generally elevated in young pediatric patients, which provides valuable reference for early diagnosis of pertussis when combined with clinical presentations.