Clinical and etiological characteristics of secondary nosocomial bacterial infections associated with infectious mononucleosis in children / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the clinical manifestations and pathogenic characteristics of nosocomial bacterial infection in children with infectious mononucleosis (IM).Methods A retrospective analysis was performed for IM children from January to December 2015 in West China Second University Hospital.According to whether there was the process of secondary bacterial infection,the patients were divided into the secondary infection group and the non-infection group.The clinical manifestations and pathogenic bacteria were analyzed.Results Two hundred and sixteen children with IM were enrolled,of whom,177 cases (81.9％) were in the non-infection group,and 39 cases (18.1％) were in the secondary infection group.The patients in non-infection group were (4.7 ± 3.2) years old,and the patients in secondary infection group were (7.0 ± 3.8) years old,and the difference was statistically significant (t =3.066,P ＜ 0.05).The secondary infection group included bacterial tonsillitis in 17 cases,bronchial pneumonia in 11 cases,otitis media in 5 cases,cervical bacterial lymphadenitis in 3 cases,periorbital cellulitis in 2 cases,and sepsis in 1 case.Meanwhile,3 cases of concomitant thrush were observed in the secondary infection group.The rate of nosocomial bacterial infection in IM children [18.1％ (39/216 cases)] was significantly higher than the incidence of nosocomial infection [1.53％ (644/41 992 cases)] in the same period,and the difference was statistically significant (x2 =368.474,P ＜ 0.01).The patients with secondary bacterial infection were treated with antibiotics,and the pathogenic bacteria were mainly gram-negative bacteria,which was consistent with pharyngeal tonsil colonization bacteria on admission.In 212 cases (98.1％) with IM,variant lymphocytes increased,and there was no significant difference between 2 groups in the variation of lymphocyte composition (x2 =2.087,P ＞ 0.05).C-reactive protein (CRP) level of IM children on admission was (11.3 ± 17.4) mg/L,while the secondary infection group was (10.2 ±9.7) mg/L and the non-infection group was (11.5 ± 18.1) mg/L,and there was no significant difference between the 2 groups (t =1.309,P ＞ 0.05).CD3 +,CD4+,CD8 + lymphocytes in the secondary infection group were 0.877 6 ± 0.031 8,0.079 0 ± 0.032 5 and 0.682 1 ± 0.053 5,compared with the non-infection group,while CD3 + lymphocytes (t =12.652,P ＜ 0.01) and CD8 + lymphocytes (t =-9.723,P ＜ 0.01) increased significantly,but the proportion of CD4+ lymphocytes decreased significantly (t =18.341,P ＜0.01).Conclusions The IM children are susceptible to nosocomial bacterial infection,which is more obvious in school-age children.Secondary respiratory tract infections are the most common type,and pathogenic bacteria may be caused by the dissemination of colonization bacteria in the pharyngeal tonsils.The CRP and variant lymphocytes on admission could not be used as the marker for predicting noscoomial bacterial infection in IM.