OBJECTIVES: To analyze the clinical characteristics of diffuse panbronchiolitis (DPB) in children and to enhance the clinical diagnosis and treatment of this disease. METHODS: A retrospective analysis was conducted on the clinical data of 6 children diagnosed with DPB who were hospitalized at The First Affiliated Hospital of Guangzhou Medical University from January 2011 to December 2019. RESULTS: Among the 6 patients, there were 2 males and 4 females; the age at diagnosis ranged from 7 to 12 years. All patients presented with cough, sputum production, and exertional dyspnea, and all had a history of sinusitis. Two cases showed positive serum cold agglutinin tests, and 5 cases exhibited pathological changes consistent with chronic bronchiolitis. High-resolution chest CT in all patients revealed centrilobular nodules diffusely distributed throughout both lungs with a tree-in-bud appearance. Five patients received low-dose azithromycin maintenance therapy, but 3 showed inadequate treatment response. After empirical anti-tuberculosis treatment, non-tuberculous Mycobacteria were found in the bronchoalveolar lavage fluid. Follow-up over 2 years showed 1 case cured, 3 cases significantly improved, and 2 cases partially improved. CONCLUSIONS The clinical presentation of DPB is non-specific and can easily lead to misdiagnosis. In cases where DPB is clinically diagnosed but does not show improvement with low-dose azithromycin treatment, special infections should be considered.
Humans ; Male ; Female ; Bronchiolitis/drug therapy* ; Retrospective Studies ; Child ; Haemophilus Infections/diagnosis*

OBJECTIVES: To investigate the carriage status of Streptococcus pneumoniae (S.pneumoniae) and Moraxella catarrhalis (M. catarrhalis) in preschool children and the influencing factors for the carriage status. METHODS: The stratified cluster sampling method was used to select 2 031 healthy children from seven kindergartens in Shunde District of Foshan in Guangdong, China. Nasal swabs were collected from all children for the isolation and identification of S. pneumoniae and M. catarrhalis. The carriage status of S. pneumoniae and M. catarrhalis was analyzed in terms of its association with demographic features and hospital- and community-related factors. RESULTS: The carriage rates of S. pneumoniae and M. catarrhalis were 21.81% and 52.44%, respectively among the children. The co-carriage rate of S. pneumoniae and M. catarrhalis was 14.87%. The correspondence analysis showed that the factors such as lower grade, non-local registered residence, living in rural areas, small living area, history of respiratory tract infection but no history of antibiotic use, allergic skin diseases, and no hospital-related exposure history were significantly associated with the co-carriage of S. pneumoniae and M. catarrhalis among the children (P<0.05). CONCLUSIONS Co-carriage of S. pneumoniae and M. catarrhalis can be observed in preschool children. Young age, poor living environment, a history of respiratory tract infection but no history of antibiotic use, allergic skin diseases, and no hospital-related exposure history are important risk factors for the co-carriage of S. pneumoniae and M. catarrhalis in preschool children.
Anti-Bacterial Agents ; Carrier State ; Child, Preschool ; Haemophilus influenzae ; Humans ; Infant ; Moraxella catarrhalis ; Nasopharynx ; Respiratory Tract Infections ; Skin Diseases ; Streptococcus pneumoniae

PURPOSE: The most common cause of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is respiratory infection. Most studies of bacterial or viral cause in AECOPD have been conducted in Western countries. We investigated bacterial and viral identification rates in AECOPD in Korea. MATERIALS AND METHODS: We reviewed and analyzed medical records of 736 cases of AECOPD at the Korea University Guro Hospital. We analyzed bacterial and viral identification rates and classified infections according to epidemiological factors, such as Global Initiative for Chronic Obstructive Lung Disease stage, mortality, and seasonal variation. RESULTS: The numbers of AECOPD events involving only bacterial identification, only viral identification, bacterial-viral co-identification, and no identification were 200 (27.2%), 159 (21.6%), 107 (14.5%), and 270 (36.7%), respectively. The most common infectious bacteria identified were Pseudomonas aeruginosa (13.0%), Streptococcus pneumoniae (11.4%), and Haemophilus influenzae (5.3%); the most common viruses identified were influenza virus (12.4%), rhinovirus (9.4%), parainfluenza virus (5.2%), and metapneumovirus (4.9%). The bacterial identification rate tended to be higher at more advanced stages of chronic obstructive pulmonary disease (p=0.020 overall, p=0.011 for P. aeruginosa, p=0.048 for S. pneumoniae). Staphylococcus aureus and Klebsiella pneumoniae were identified more in mortality group (p=0.003 for S. aureus, p=0.009 for K. pneumoniae). All viruses were seasonal (i.e., greater prevalence in a particular season; p < 0.050). Influenza virus and rhinovirus were mainly identified in the winter, parainfluenza virus in the summer, and metapneumovirus in the spring. CONCLUSION: This information on the epidemiology of respiratory infections in AECOPD will improve the management of AECOPD using antibiotics and other treatments in Korea.
Anti-Bacterial Agents ; Bacteria ; Epidemiology ; Haemophilus influenzae ; Klebsiella pneumoniae ; Korea ; Medical Records ; Metapneumovirus ; Mortality ; Orthomyxoviridae ; Paramyxoviridae Infections ; Prevalence ; Pseudomonas aeruginosa ; Pulmonary Disease, Chronic Obstructive ; Respiratory Tract Infections ; Rhinovirus ; Seasons ; Staphylococcus aureus ; Streptococcus pneumoniae

Child ; Consensus ; Haemophilus Infections ; diagnosis ; therapy ; Haemophilus influenzae ; Humans ; Infant

To establish a novel colloidal gold immunochromatography assay (GICA) for rapid, sensitive and accurate detection of Haemophilus influenzae infection by using the outer membrane protein P6 as detection target. First, the linear antigen epitope located in the extracellular domain of the P6 protein (GenBank accession number: AGH02799) was predicted by bioinformatics analysis. The region (62-75 aa of the protein) with strong antigen specificity was chosen and synthesized. Two rabbits were then immunized by the polypeptides (14 aa) for production of polyclonal antibodies. Then, the recombinant P6 proteins were also obtained to produce polyclonal antibodies. Finally, based on the two antibodies, a novel colloidal GICA for detection of Haemophilus influenzae infection was established and the specificity, sensitivity, repeatability and stability of this method were evaluated. At the same time, the method was tested in clinical simulation, and the plate culture method was used to verify its accuracy. The test strip for Haemophilus influenzae infection was successfully prepared. The detection limit of the test strip was as low as 1×105 CFU/mL and the whole process can be completed within 15 minutes. The strip specifically recognized Haemophilus influenzae and did not react with nine of other common respiratory pathogens such as Streptococcus pneumoniae, Moraxella catarrhalis, Mycoplasma pneumonia, and Legionella pneumophila. And the strips could be stored at 25 °C for at least 6 months without losing sensitivity or specificity. The coincidence rate between the results of 200 clinical samples and the plate culture method was 90.5%. Haemophilus influenzae protein P6, which possessed a high degree of surface antigen accessibility and antigencity, could be used as a marker for Haemophilus influenzae detection. The immunochromatographic colloidal gold test strip which bears the features of rapidity, convenience and sensitivity provides a unique tool for the on-site surveillance and diagnosis of Haemophilus influenzae infection in clinical test.
Animals ; Chromatography, Affinity ; instrumentation ; Diagnostic Tests, Routine ; standards ; Gold Colloid ; chemistry ; Haemophilus Infections ; diagnosis ; Haemophilus influenzae ; Humans ; Limit of Detection ; Rabbits ; Sensitivity and Specificity

OBJECTIVE: To study the features of pathogens in children with lower respiratory tract infection. METHODS: A total of 108 children who were hospitalized due to lower respiratory tract infection and underwent fiber bronchoscopy between January 2017 and June 2018 were enrolled. Bronchoalveolar lavage fluid samples were collected. Multiple quantitative real-time PCR was performed to detect pathogens. RESULTS: Of the108 children, 85 (78.7%) were found to have pathogens, among whom 52 (48.1%) had single pathogen infection and 33 (30.6%) had multiple pathogen infections. Mycoplasma pneumoniae was detected in 38 children (35.2%), and was the most common pathogen. The children aged 36 - <72 months had the highest detection rate of Mycoplasma pneumoniae. Both Streptococcus pneumoniae and Haemophilus influenzae were detected in 29 children (26.9%) and Streptococcus pneumoniae was mainly detected in children aged <24 months. Each of Acinetobacter baumannii, Candida albicans and Klebsiella pneumoniae was detected in 3 children. Among the 31 children with bronchopneumonia, 9 were found to have Haemophilus influenza, with the highest detection rate of 29%. Among the 34 children with lobar pneumonia, 22 were found to have Mycoplasma pneumoniae, with the highest detection rate of 65%. Among the 22 children with bronchial foreign bodies and bronchopneumonia, 10 were found to have Streptococcus pneumoniae, with the highest detection rate of 45%. CONCLUSIONS In children with lower respiratory tract infection, Mycoplasma pneumoniae is the most common pathogen, followed by Streptococcus pneumoniae and Haemophilus influenzae. There are differences in the detection rates of pathogens between children with different ages and different types of lower respiratory tract infection.
Bronchoalveolar Lavage Fluid ; Child ; Child, Preschool ; Haemophilus influenzae ; Humans ; Infant ; Mycoplasma pneumoniae ; Respiratory Tract Infections ; Streptococcus pneumoniae

OBJECTIVE: To study the bacteriologic profile and drug resistance of respiratory infection in children, and to provide a basis for etiological diagnosis and rational use of antimicrobial agents. METHODS: A retrospective analysis was performed for 15 047 children who attended the hospital due to respiratory infection from January 2016 to December 2018. Their sputum samples were collected, and the Phoenix-100 automatic microbial identification system was used for the identification and drug sensitivity analysis of the isolated pathogenic bacteria. RESULTS: Of all 17 174 sputum samples detected, there were 2 395 positive samples, with a positive rate of 13.95%; a total of 2 584 strains of pathogenic bacteria were isolated, among which there were 1 577 (61.03%) Gram-negative strains, 967 (37.42%) Gram-positive strains, and 40 (1.55%) fungal strains. The most common pathogen was Haemophilus influenzae (33.90%), followed by Streptococcus pneumoniae (33.55%), Moraxella catarrhalis (19.20%), and Staphylococcus aureus (3.64%). Among the 2 331 children with positive infection, 251 had mixed infection, most commonly with Haemophilus influenzae and Streptococcus pneumoniae. The detection rate of pathogenic bacteria was higher in winter and spring and lower in summer and autumn. There was a significant difference in the detection rate of pathogenic bacteria between different age groups (P<0.05), with the highest detection rate in infants aged 1 month to <1 year. Streptococcus pneumoniae and Staphylococcus aureus had a sensitivity rate of 100% to vancomycin, linezolid, and teicoplanin, and Haemophilus influenzae had a lower sensitivity rate to ampicillin, compound sulfamethoxazole and cefuroxime and a higher sensitivity rate to other drugs. CONCLUSIONS Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis are the main pathogenic bacteria of respiratory infection in children, and mixed infection is the most common type of infection. The detection rate of pathogenic bacteria varies across seasons and ages. Different pathogenic bacteria have different features of drug resistance, and antibiotics should be selected based on drug sensitivity results.
Anti-Bacterial Agents ; Child ; Drug Resistance ; Haemophilus influenzae ; Humans ; Infant ; Infant, Newborn ; Microbial Sensitivity Tests ; Moraxella catarrhalis ; Respiratory Tract Infections ; Retrospective Studies

Since the implementation of conjugate Haemophilus influenzae serotype b (Hib) vaccine, the rate of infections caused by Hib has dramatically decreased, and the proportion of infections caused by non-type b H. influenzae has increased. Cerebral venous sinus thrombosis (CVST) is rare; however, it should be considered as a potential complication of bacterial meningitis. Herein, we report about a child who developed CVST after being diagnosed with H. influenzae serotype f meningitis.
Bacteremia ; Central Nervous System Infections ; Cerebrospinal Fluid ; Child ; Haemophilus influenzae type b ; Haemophilus influenzae ; Haemophilus ; Humans ; Influenza, Human ; Meningitis ; Meningitis, Bacterial ; Meningitis, Haemophilus ; Sepsis ; Serogroup ; Sinus Thrombosis, Intracranial

Eight rabbits exhibited head tilt and subsequently died. At necropsy, three rabbits had crusty deposits in ears and four had reddish lungs. The main histopathological features were severe diffuse suppurative meningoencephalitis (75.0% of rabbits), fibrinopurulent pneumonia (37.5%), and otitis externa (37.5%). Pasteurella multocida (P. multocida) was isolated from brains, ears, and lungs. The capsular serogroups of the isolates were untypable. Based on histopathological features and bacterial analysis results, the rabbits were diagnosed as P. multocida infection. P. multocida infections might result in considerable economic loss in commercial rabbit production facilities in Korea.
Brain ; Ear ; Head ; Korea ; Lung ; Meningoencephalitis ; Otitis Externa ; Pasteurella Infections ; Pasteurella multocida ; Pasteurella ; Pneumonia ; Rabbits ; Serogroup

Pasteurella multocida serotype B:2 causes hemorrhagic septicemia in cattle and buffalo. The invasion mechanism of the bacterium when invading the bloodstream is unclear. This study aimed to characterize the effects of immunomodulatory molecules, namely dexamethasone and lipopolysaccharide, on the invasion efficiency of P. multocida serotype B:2 toward bovine aortic endothelial cells (BAECs) and the involvement of actin microfilaments in the invasion mechanism. The results imply that treatment of BAECs with lipopolysaccharide at 100 ng/mL for 24 h significantly increases the intracellular bacteria number per cell (p < 0.01) compared with those in untreated and dexamethasone-treated cells. The lipopolysaccharide-treated cells showed a significant decrease in F-actin expression and an increase in G-actin expression (p < 0.001), indicating actin depolymerization of BAECs. However, no significant differences were detected in the invasion efficiency and actin filament reorganization between the dexamethasone-treated and untreated cells. Transmission electron microscopy showed that P. multocida B:2 resided in a vacuolar compartment of dexamethasone-treated and untreated cells, whereas the bacteria resided in cellular membrane of lipopolysaccharide-treated cells. The results suggest that lipopolysaccharide destabilizes the actin filaments of BAECs, which could facilitate the invasion of P. multocida B:2 into BAECs.
Actin Cytoskeleton ; Actins ; Animals ; Bacteria ; Buffaloes ; Cattle ; Dexamethasone ; Endothelial Cells ; Hemorrhagic Septicemia ; In Vitro Techniques ; Membranes ; Microscopy, Electron, Transmission ; Pasteurella multocida ; Pasteurella ; Serogroup