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Objective: To investigate the changes of the distribution and drug resistance profile of bacteria from ICU children with lower respiratory tract infection (LRTI) in Suzhou City, Jiangsu Province from 2017 to 2022. Methods: From January 2017 to December 2022, a cross-sectional observational study on the bacterial spectrum analysis among intensive care unit (ICU) children with LRTI was conducted in Children's Hospital of Soochow University. The bacteria was cultivated by culture methods from sputum samples, and identified by MALDI-TOF mass spectrometry. Drug sensitivity tests were performed by the VITEK2 Compact fully automated analysis system and the paper slide method. The χ 2 test or Fisher's exact probability was used to analyze the changes of the distribution of sputum culture-positive bacteria and drug resistance in ICU children. Results: The overall detection rate of sputum culture was 42.06% (1 182/2 810). Staphylococcus aureus (25.63%,303/1 182), Acinetobacter baumannii (13.62%,161/1 182) and Haemaphilus influenzae (13.28%,157/1 182) were the top three. Proportions of Acinetobacter baumannii (17.90% vs. 11.02%, χ ²=11.17, P =0.001), especially carbapenem-resistant Acinetobacter baumannii (43.70% vs. 23.50%, χ² =15.21, P <0.001) increased significantly from 2020 to 2022. However, the proportions of Haemophilus influenzae (8.50% vs. 16.19%, χ ²=14.27, P <0.001), Streptococcus pneumoniae (8.50% vs. 15.92%, χ ²=13.42, P <0.001) and extended-spectrum-lactamase producing Escherichia coli (8.89% vs. 18.00%, χ ²=5.45, P =0.025) decreased. Drug resistant results showed that Acinetobacter baumannii was obviously more resistant to imipenem ( χ² =4.43, P =0.035) and levofloxacin ( χ ²=12.53, P <0.001), while more sensitive to minocycline ( χ ²=8.34, P =0.004). Escherichia coli showed a significant increase in resistance to piperacillin tazobactam ( χ ²=8.29, P =0.008) and cefoperazone sulbactam ( χ ²=5.07, P =0.024) from 2020 to 2022; Klebsiella pneumoniae consistently maintained a resistance rate of more than 60% to first and second-generation cephalosporins, and remain susceptible to quinolones and carbapenems. Staphylococcus aureus remained highly susceptible to levofloxacin (drug resistance rate: 2.31%,7/303) and sulfamethoxazole/trimethoprim (drug resistance rate: 4.95%,15/303) from 2020 to 2022. Conclusion: Higher detection and resistance rates of Acinetobacter baumannii from sputum culture in ICU children from 2020 to 2022 were explored. Resistance of Escherichia coli to β-lactamase inhibitor combinations was more serious. Regular monitoring the changes of the etiology of respiratory tract infections in ICU Children is particularly important for the prevention and treatment of multidrug-resistant bacterial infections.

Objective: To investigate the clinical characteristics of invasive Haemophilus influenzae (HI) infection in children. Methods: The clinical manifestations, laboratory examinations and treatment outcomes of 84 children with HI infection confirmed by bacterial culture in 7 tertiary children's hospitals from 2014 to 2018 were analyzed retrospectively. Results: Among the 84 cases, 50 were males. The age was 1.54 years (ranged from 5 days to 13 years).Twenty cases (24%) had underlying diseases and 48 cases (57%) had not received antibiotics before collecting specimens. Eighty-two cases (98%) had fever and 75 cases (89%) had clear infection foci, among which 31 cases (37%) had meningitis and 27 cases (32%) had pneumonia. Blood culture was positive in 62 cases (74%), cerebrospinal fluid culture was positive in 10 cases (12%), blood culture and cerebrospinal fluid culture were both positive in 11 cases (13%). Antibiotics susceptibility test showed that 27% (22/82) of all HI strains produced β-lactamases and 48% (37/77) strains were resistant to ampicillin. The drug resistance rates to cefuroxime, ampicillin-sulbactam, trimethoprim-sulfamethoxazole and azithromycin were 25% (20/80) , 20% (9/45) , 71% (44/62) and 19%(11/58), respectively. All strains were sensitive to meropenem, levofloxacin and ceftriaxone. After sensitive antibiotic therapy, 83% (70/84) of all patients were cured and improved, the mortality rate and loss of follow-up rate were 13% (11/84) and 4% (3/84) respectively. Conclusions: Meningitis and pneumonia are common presentation of invasive HI infections in children. Mortality in HI meningitis children is high and the third generation of cephalosporins, such as ceftriaxone can be used as the first choice for the treatment of invasive HI infection.

Objective: To analyze epidemiological characteristics of acute bacterial meningitis (ABM) cases and the common pathogens infected in Jinan, Shandong Province. Methods: Epidemiological and clinical informations and cerebrospinal fluid (CSF) and blood specimens of acute meningitis/encephalitis syndrome (AMES) cases (total 3 918 cases) were collected in the six sentinel hospitals from 2013 to 2016. neisseria meningitidis (Nm) , streptococcus pneumoniae (Sp) and haemophilus influenza (Hi) were detected by the methods of real-time fluorescent quantitative polymerase chain reaction (Real-time PCR), bacterial culture and latex agglutination. χ(2) test was used to compare ABM cases with different feasures, and compare the difference of Nm, Sp and Hi cases in clinical and epidemiological characteristics. Results: A total of 479 cases were diagnosed as ABM from 2013 to 2016, 82 cases of which were laboratory confirmed, including 54 cases infected with Nm , 25 cases infected with Sp , and 3 cases infected with Hi . The disease course in different age groups of ABM cases has statistically difference (χ(2)=40.95, P< 0.001). The disease course of under 6 (63.6%, 161/253) and 7 to 17 (55.9%, 33/59) years old ABM cases mainly required 14-28 days, and over 18 years old cases mainly required less than 14 days (59.9%, 100/167). For Nm cases, there was a main onset period from October to March (75.9%, 41/54); on the disease course, under 6 (81.0%, 17/21) and 7 to 17 (16/18) years old cases mainly required less than 14 days, while over 18 years old cases mainly required 14-28 days (8/15), and there was a statistically difference in different age groups (χ(2)=8.44, P= 0.015). For Sp cases, the major onset period was from December to May (84.0%, 21/25); on the disease course, all of under 6 and 7 to 17 years old cases were required 14-28 days, while over 18 years old cases mainly required less than 14 days (9/17), and there was a statistically difference in different age groups (χ(2)=6.62, P= 0.037). 91.0% of the ABM cases (436/479) were healed or improvement, with the relatively higher ratio in under 6 (94.9%, 240/253) and 7 to 17 (98.3%, 58/59) years old groups, and poorer ratio in over 18 years old group (82.6%, 138/167), and the difference was significant in different age groups (χ(2)=22.77, P< 0.001). For Nm, Sp and Hi cases, the ratio of cases that were healed or improvement were 87.0% (47/54), 92.0% (23/25) and 3/3, respectively, and there were no death cases. Conclusion: ABM cases were found mostly in under 18 years old group in Jinan, Shandong Province, and the bigger age group had poor prognosis. Nm was the major pathogen causing ABM, followed by Sp and Hi . Distinguished differences of epidemiological characteristics were found on ABM cases suffered with different pathogens infected.

Objective: To investigate the bacteriologic characteristics of recurrent acute rhinosinusitis(RAR). Method: Twenty-nine patients (29 with RAR) from outpatient clinic in our hospital between June 2010 and May 2016 were enrolled in the study. Specimens of the middle meatus or olfactory cleft area using the sinus endoscopy through were transported to the laboratory for bacterial culture. Result: Twenty-five specimens out of 29 were bacterial culture positive (culture positive rate was 86.2%).A total of 32 isolates (25 aerobic or facultative and 7 anaerobic) were recovered from the 29 cases of RAR. The predominant aerobic or facultative bacteria were Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Staphylococcus aureus. The predominant anaerobic bacteria were Bacteroides fragilis and Propionibacterium. Antibiotic susceptibility tests showed that the resistance rate of these aerobic or facultative bacteria to Macrolides (Erythromycin and Azithromycin) and quinolones (Levofloxacin) was 88% and 92%, respectively. Similarly, the resistance rate of bacteria to β-lactamase antibiotics (penicillin, ampicillin, and cefazolin) was also greater than 90% (100%, 92%, and 92%, respectively). But the drug resistance of these bacteria to the thirdgeneration cephalosporin combined with beta lactamase inhibitors (Cefoperazone/sulbactam) was 20%. Among the 7 strains of anaerobic bacteria, 6 strains were sensitive to ornidazole. Conclusion: The major pathogens of RAR are the aerobic and facultative bacteria Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Staphylococcus aureus, most of which are resistant to commonly used antibiotics., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Objective: To analyze the clinical characteristics of protracted bacterial bronchitis (PBB) in children., Method: The clinical data of patients seen from October, 2010 to March, 2014 in Department of Respiratory Diseases of our hospital were retrospectively analyzed. Inclusion criteria were over 4 weeks cough, receiving fiberoptic bronchoscopy, positive bacterial culture and (or) the increased percentage of neutral granulocytes in bronchoalveolar lavage fluid (BALF)., Result: Twenty eight patients were involved, 26 were male (93%) and two were female (7%). The median age of patients was 8.5 months. The median duration of cough was four weeks. The average length of hospital stay was (8.3 ± 3.9)days. The main clinical feature was wet cough in 28 cases, wet cough with wheezing was seen in 21 cases. The wet cough phase distribution was irregular in 21 cases. The crackles with wheeze (in 21 cases) was main signs of PBB. The percentage of CD3⁻ CD16⁺ 56⁺ cells increased in peripheral blood. The fiberoptic bronchoscopic manifestations of PBB were luminal mucosal edema. Eleven patients also had airway malacia. The neutrophil median in BALF was 0.2. The positive rate of bacterial culture of BALF was 36%. The main bacteria were Streptococcus pneumoniae (50%) and Haemophilus influenzae (30%). The main treatment for PBB patients included amoxycillin/clavulanate potassium and second-generation cephalosporins. The average duration of treatment was (17.3 ± 3.2)days, the prognosis was good., Conclusion: PBB is common in male infants. Persistent wet cough with wheezing was the main characteristic of PBB. PBB is commonly accompanied by immune dysfunction and airway malacia, and the pathogens were Streptococcus pneumoniae and Haemophilus influenzae.

Objective: To investigate the basic clinical characteristics and drug resistance of Haemophilus influenzae (Hi) infection in hospitalized children in the past two years., Methods: A retrospective cross-sectional study was conducted to analyze Hi strains isolated from the sputum and pharyngeal swabs of children aged 0-17 years who were hospitalized in the Third People's Hospital of Chengdu between June 2011 and May 2013., Results: A total of 117 strains were isolated from 111 hospitalized children. There were 102 cases (91.9%) of respiratory infection and 9 cases (8.1%) of other diseases. The positive rates of Hi in children with bronchopneumonia or pneumonia (50.8%, 30/59) and in children with acute laryngotracheobronchitis (50.0%, 2/4) were relatively high, followed by in children with capillary bronchitis (34.6%, 9/26), in children with acute bronchitis (24.2%, 32/132), in children with herpangina (19.0%, 4/21), in children with asthmatoid bronchitis (17.9%, 5/28), in children with acute upper respiratory tract infection (11.8%, 9/76), in children with acute tonsillitis (8.2%, 7/85), and in children with neonatal pneumonia (5.6%, 3/54). There were significant differences in the rates of resistance to amoxicillin-clavulanate (15% vs 23%; P=0.010) and chloramphenicol (25% vs 8%; P=0.015) between the two survey years. The frequencice of β-lactamase-nonproducing-ampicillin-resistant (BLNAR) strains and β-lactamase-producing-amoxicilli/clavulanate-resistant (BLPACR) strains increased from 12% to 21% and from 13% to 19% respectively during the two survey years (P>0.05)., Conclusions: Hi plays an important role in the respiratory tract infection of children aged 0-17 years. The increasing trend of BLNAR and BLPACR rates makes it harder for antibiotic selection in clinical practice.

Objective: To research the prevalences of four kinds of bacteria including Alloiococcus otitidis, Streptococcus pneumonia, Haemophilus influenzae, and Moraxella catarrhalis in children with chronic otitis media with effusion (SOM) of the middle ear effusion, and the reproduction of the nasopharynx, so as to explore their meaning for the children with SOM., Method: Alloiococcus otitidis, Streptococcus pneumonia, Haemophilus influenza, and Moraxella catarrhal were investigated in the samples obtained from middle ear effusion and nasopharyn- geal swabs, using PCR and conventional bacterial culture methods., Result: By bacterial culture, the pathogen detection rate from middle ear effusion was 3.6%,while the nasopharynx was 54.0%, the detection rate of Streptococcus pneumonia, Haemophilus influenza, Moraxella catarrhalis was 10.8%, 27.0%, 4.5%, respectively, the drug susceptibility results for 51 samples of bacterial culture positive showed that 39 cases was sensitivite to the β-lactam antibiotic; By PCR, the number of detecting various kinds of bacteria simultaneously in middle ear effusion or in the nasopharynx were 6 and 34. The bacteria prevalences of S. pneumoniae, H. influenzae, M. catarrhalis, and A. otitidis are 5.4%, 5.4%, 3.6%, and 42.3% in the middle ear effusion, are 25.2%, 27.0%,13.5% and 34.2% in nasopharyngeal, respectively., Conclusion: (1) PCR method is more sensitively detecting the bacteria than conventional bacterial culture methods. (2) The chronic SOM of children may be a combination of mixed bacterial infection, A. otitidis may be the most common pathogen of children SOM. (3) For children of SOM, if antibiotics are chosen to be used early in the disease, we suggest using the β-lactam antibiotics.

Objective: To investigate the etiology of community-acquired respiratory tract infections (CARTI) and the antimicrobial resistance of the major pathogens in primary hospitals in Shanghai., Methods: Patients with CARTI were prospectively recruited from 30 primary hospitals from December 2007 to July 2010. Those who had used antimicrobials within previous 2 weeks were excluded from the study. The clinical information such as temperature, white blood cell (WBC) count and percentage of neutrophils was recorded, and throat swab or deep cough sputum was collected to isolate pathogens. The specimens were collected and couriered to the Zhongshan Hospital microbiology laboratory within 2 h for bacterial culture. The minimal inhibition concentrations (MIC) of penicillin G, amoxicillin, cephradine, cephalexin, cefadroxil, sulfamethoxazole/trimethoprim and azithromycin were determined using the agar dilution test., Results: Totally 806 qualified cases were enrolled in this study. Fever (T ≥ 38 °C) was present in 51.7% (n = 417) , and increased WBC count (>10×10(9)/L) was noted in 68.5% (n = 552 cases) of the patients. For bacterial culture, 184 strains were isolated from throat swabs of 688 patients with upper respiratory infection; the most frequently isolated bacteria were Haemophilus influenzae (44, 23.9%), Staphylococcus aureus (44, 23.9%) and Group G streptococcus (43, 23.0%). Thirty-three strains were isolated from 118 patients with lower respiratory infections, with Haemophilus influenza (21, 63.6%), Group G streptococcus (6,18.2%) and Streptococcus pneumoniae (3,9.1%) as the leading pathogens. All strains of Haemophilus influenzae were susceptible to azithromycin. The susceptibility rate of Streptococcus pneumoniae to penicillin was as high as 94.7%, while that to azithromycin was significantly decreased (21.1%). The MIC90 values of cephalexin, cefadroxil and ceftazidime for β-hemolytic streptococcus spp were ≤ 2 mg/L., Conclusions: Upper respiratory infections were responsible for most cases of CARTI. The commonly used antimicrobials in primary hospitals kept a high susceptibility to the frequent pathogens for CARTI. However, Streptococcus pneumoniae showed a decreased susceptibility to macrolides, which should be used carefully as a single agent when treating CARTI.

Objective: To investigate the drug-resistance rates of community-acquired respiratory tract pathogens isolated from adults in China during 2009 and 2010., Methods: A total of 1793 strains (S. aureus 421, S. pneumoniae 420, K. pneumoniae 404, H. influenzae 313, other Streptococcus. spp 149, and M. catarrhalis 86) of non-duplicated community-acquired respiratory tract pathogens were isolated from 11 hospitals in 6 cities. The MIC values were determined by the broth microdilution method, and the production of β-lactamase was tested using a nitrocefin-based test., Results: All of the S.aureus isolates were methicillin-sensitive (MSSA). Of the MSSA isolates, less than 1% (4/421) was resistant to β-lactamase inhibitor combinations, about 13.1% (55/421) and 9% (38/421) resistant to levofloxacin and moxifloxacin, and 57% (240/421), 53.2% (224/421), and 88.7% (373/421) resistant to azithromycin, clarithromycin, and penicillin, respectively. No S. aureus isolates resistant to vancomycin were detected in this study. Based on different criteria, the percentages of penicillin-sensitive S. pneumoniae (PSSP), penicillin-intermediate S. pneumoniae (PISP), and penicillin-resistant S. pneumoniae (PRSP) were 24.4% (102/420), 27.3% (115/420), 48.3% (203/420) (Oral) and 1.9% (8/420), 9% (38/420), 89.1% (374/420) (parenteral), respectively. The resistance rates of S. pneumonia to azithromycin, clarithromycin, cefaclor, cefuroxime, ceftriaxone and amoxicillin with clavulanic acid were 88.2% (370/420), 87.4% (367/420), 45.3% (190/420), 41.9% (176/420), 10.2% (43/420), and 5.2% (22/420), respectively. About 2.6% (11/420) and 0.2% (1/420) of S. pneumonia isolates were resistant to levofloxacin and moxifloxacin. More than 70% (104/149) of β-hemolytic streptococci isolates were resistant to azithromycin and clarithromycin, and about 10.1% (15/149) of isolates were resistant to levofloxacin. The resistance rates of K.pneumonia to most antibiotics were > 20% (81/404), and that of ceftazidime was lower than cefuroxime, cefaclor, and ceftriaxone. The mean prevalence value of ESBL producing K. pneumonia was 38.8% (157/404), with significantly regional variations. More than 90% of H. influenza and M. catarrhalis were susceptible to most antibiotics, with resistance rate of < 5% (16/313, H. influenza; 4/86, M. catarrhalis). The mean productions of β-lactamase in H. influenza and M. catarrhalis were 13.1% (41/313) and 91.7% (79/86), respectively., Conclusions: The percentage of PRSP increased significantly, and the resistance rates of community-acquired respiratory tract pathogens to common antibiotics such as macrolide and cephalosporins increased gradually. New fluoroquinolones such as moxifloxacin showed a high antimicrobial activity against most of the respiratory pathogens.

Objective: To investigate the pathogenic bacteria distribution and drug susceptibility in children with acute otitis media (AOM) in different age and different season in the Pearl River Delta region., Method: Four hundred and forty-two children diagnosed as AOM were divided into three groups by age factor and four groups by season factor. Midge ear pus collecting and culturing were used for bacteria and antimicrobial susceptibility test., Result: (1) Strains of bacteria were isolated from 356 children with the positive rate of 80.5%. Streptococcus pneumoniae (39.2%), staphylococcus aureus (25.9%) and haemophilus influenzae (7.4%) were the most frequently isolated pathogens. (2) Streptococcus pneumoniae was the main pathogenic bacteria in 0-1 year group and > 1-3 years group (P < 0.05), staphylococcus aureus was the most frequently isolated pathogen in >3 years group (P < 0.05); (3) In the season groups, the number of children with AOM decreased significantly in July-September group. There was no significant difference of streptococcus pneumoniae distribution among the four groups (P > 0.05). Staphylococcus aureus was the main pathogen in January-March group (P < 0.05); (4) Drug sensitivity shown that linezolid and ofloxacin were most sensitive to streptococcus pneumoniae and staphylococcus aureus, and macrolides had a good therapy effect to haemophilus influenzae., Conclusion: The pathogens distribution and drug susceptibility in children with AOM were varies in different age and different season. As a result, a treatment should be done based on the climate, environment, and pathogens distribution of a region.

Objective: This research was to explore the difference between children with community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP) in the composition and antibiotic-resistance of pathogenic bacteria., Methods: 241 CAP and 116 HAP with positive sputum culture who were hospitalized from January to December in 2008 in Children's Hospital Affiliated to Suzhou University were selected in this study. The bacteria were identified by traditionally manual method and antibiotic sensitivity tests were performed by K-B method. The chi-square or Fisher's exact test were used for statistical test., Results: In 241 CAP, Streptococcus pneumoniae and haemophilus influenza accounted for (42.2%, 106/251) and (12.4%, 31/251) infection, respectively; however in 116 HAP, Enterobacteriaceae and Non-fermenters accounted for (88.2%, 127/144). In addition, methicillin-resistant Staphylococcus aureus weren't isolated, however, its detection rate was 66.7% in HAP. The drug resistance was 1.5 times higher in HAP than that in CAP for several types of antibiotics, such as ceftazidime (37.5% (6/16) vs 75.6% (31/41)), cefepime (37.5% (6/16) vs 78.0% (32/41)), aztreonam (50.0% (8/16) vs 90.2% (37/41)), cefoperazone/sulbactam (12.5% (2/16) vs 51.2% (21/41)) and piperacillin/tazobactam (12.5% (2/16) vs 56.0% (23/41)). Klebsiella pneumoniae isolated from HAP had higher drug resistance than that isolated from CAP against some antibiotics, for example, gentamicin (0 vs 63.6% (7/11)), SMZ + TMP (20.0% (1/5) vs 63.6% (7/11)) and cefoperazone/sulbactam (0 vs 54.5% (6/11)). We also found Enterobacter cloacae isolated from HAP showed high drug resistance than that isolated from CAP against imipenem (0 vs 46.7% (7/15)), aztreonam (9.1% (1/11) vs 60.0% (9/15)) and cefoperazone (18.2% (2/11) vs 80.0% (12/15)) and Pseudomonas aeruginosa from HAP had higher resistance than that from CAP against gentamicin (0 vs 50.0% (9/18)), amikacin (0 vs 38.9% (7/18)), ceftazidime (0 vs 55.6% (10/18)), cefepime (0 vs 50.0% (9/18)) and cefoperazone (33.3% (2/6) vs 94.4% (17/18)). The detection rates of ESBLs for Escherichia coli were 84.6% (11/13) and 93.3% (14/15) in CAP and HAP, respectively (χ(2) = 0.553, P > 0.05); while for Klebsiella pneumoniae, they were 81.3% (13/16) and 95.1% (39/41), respectively (χ(2) = 2.767, P > 0.05)., Conclusion: CAP was mainly comprised of Streptococcus pneumoniae and haemophilus influenza; while HAP was mainly comprised of Enterobacteriaceae and Non-fermenters. The drug resistance of gram-negative bacilli was higher in HAP than that in CAP.

Objective: To investigate the antimicrobial resistance of community respiratory pathogens isolated in China., Methods: The strains of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, S. pyogenes were isolated from patients with community-acquired respiratory tract infections at 14 Chinese hospitals from 2005 to 2007. Etest and disk diffusion methods were used to survey the susceptibility of 14 antibiotics against these strains. These antibiotics included penicillin G, ampicillin, amoxicillin/clavulanic acid, cefaclor, cefprozil, ceftriaxone, cefepime, levofloxacin, gatifloxacin, ciprofloxacin, tetracycline, clindamycin, erythromycin and trimethoprim/sulfamethoxazole (SXT)., Results: A total of 1870 strains were collected including S. pneumoniae (n = 997), S. pyogenes (n = 176), H. influenzae (n = 499) and M. catarrhalis (n = 198). The 2005 - 2007 prevalence of penicillin-susceptible S. pneumoniae (PSSP) were 92.6%, 73.9%, 74.1% and penicillin-intermediate S. pneumoniae (PISP) 4.5%, 9.5%, 14.3% and penicillin-resistant S. pneumoniae (PRSP) 2.9%, 16.6%, 11.6% respectively. 36.9% of S. pneumoniae strains isolated from or= 92.9%., Conclusions: Antimicrobial resistance in S. pneumoniae is rising. The prevalence of PNSSP isolated from children < or = 6 years old is higher than other age groups. Amoxicillin-clavulanic acid, ceftriaxone, cefepime, gatifloxacin and levofloxacin remain highly active against common community respiratory pathogens.

Objective: To Investigate the rate of carrying virus of Haemophilus influenzae in population of Shenzhen., Methods: Cross-sectional study was applied and 380 samples were recruited by cluster sampling in April to July 2008. The identification of H. influenzae strains were done according to the loboratory standard methodology described by Manual of Clinical Microbiology (American). All strains were biotyped according to Kilian's classification with the API NH system. And serotyped by a slide agglutination assay with type to a specific antiserum as described by Pittman. PCR method for identification of H. infiuenzae were performed as described by Falla., Results: The rate of carrying Haemophilus influenzae in population was 31.84% (121/380). The rate of 6-year groups was the highest (54.90%). The rate of 50-year groups was the lowest (8.51%). The rate of carrying Haemophilus influenzae had significant difference by age groups (chi2 = 30.172 P < 0.005). Eight biotypes were found among the 139 H. influenzae isolates. 7.91% (11/139) of all isolates belonged to biotype I, 37.41% (52/139) were biotype II, 34.53% (48/139) were biotype III, 4.32% (6/139) were biotype IV, 7.91% (11/139) were biotype V, 0.72% (1/139) were biotype VI, 6.47% (9/139) were biotype VII and 0.72% (1/139) were biotype VIII respectively. 97.14% (170/175) were nontypeable. There were five isolates were typeable. Two were serotype b. Three were serotype e. The rate of producing beta-lactamase was 14.38% (20/139)., Conclusion: The rate of carrying Haemophilus influenzae in healthy population of Shenzhen was high. The main isolates were type II and III. And the isolates were nontypeable H. influenzae primarily.

Objective: Bacterial cultures from respiratory aspirate or sputum have been the conventional diagnostic method for pneumonia, but the results of culture was often affected by early extensive use of antibiotics, sample collection and delivery. The objective of this study was to explore application of the combined detection of culture and polymerase chain reaction (PCR) assay in hospitalized children with pneumonia., Methods: Totally 187 hospitalized children with pneumonia were enrolled. The age of the patients ranged from 1 month to 10 years, 124 were male, 63 female; 175 of the patients received antibiotics treatment before admission. Deep respiratory aspirate sample from patients was cultured by Streptococcus pneumoniae selective plate, Hemophilus influenzae selective plate and conventional plate. The aspirate samples were also amplified for DNA of 14 bacteria with target enriched multiplex polymerase chain reaction (Tem-PCR) and detected with Luminex xMAP technology platform., Results: The total positive rate by bacterial culture was 40.1% (75/187), of which 17.1% (24/187) were Hemophilus influenzae b, 8.6% (16/187) were Escherichia coli, 6.4% (12/187) were Klebsiella pneumoniae, 4.8% (9/187) were Staphylococcus aureus, 3.7% (7/187) were Streptococcus pneumoniae, 1.6% (3/187) were Pseudomonas aeruginosa, 1.1% (2/187) were Acinetobacter baumannii, and 1.1% (2/187) were Enterobacter cloacae. The total positive rate by combined detection of culture and Tem-PCR assay were 78.6% (147/187), of which 28.9% (54/187) were Hemophilus influenzae b, 19.3% (36/187) were Streptococcus pneumoniae, 8.6% (16/187) were Escherichia coli, 6.4% (12/187) were Klebsiella pneumoniae, 5.9% (11/187) were Staphylococcus aureus, 5.9% (11/187) were Acinetobacter baumannii, 2.7% (5/187) were Pseudomonas aeruginosa, and 1.1% (2/187) were Enterobacter cloacae., Conclusion: The Tem-PCR assay may increase the detection rate of Hemophilus influenzae b, Streptococcus pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii. The Combined detection may increase the positive rate of bacterial pathogens in hospitalized children with pneumonia, and the results might reflect the real patterns of bacterial etiology. The Tem-PCR needs further improvement for diagnosis of Escherichia coli and Klebsiella pneumoniae.

Objective: To develop a rapid method for detecting Haemophilus influenzae by multiplex polymerase chain reaction (M-PCR)., Methods: Primers (Hi) were designed for amplification of p6 gene coding P6 protein of Haemophilus influenzae, which was used to identify Haemophilus influenzae species. Primers (Hi-cap) were designed for amplification of bexA gene which coding capsular polysaccharide (cap) synthesis was used for detecting whether Haemophilus influenzae isolates possess bexA gene relating to cap synthesis. Twelve primers (Hia-Hif) were designed for amplification of cap synthesis gene to identify the cap-type of Haemophilus influenzae. Other relative enteric pathogenic bacteria were amplified by M-PCR to serve as controls. 200 strains isolated from patients were identified. Results from M-PCR were compared to two methods including V and X factors grow requirement test and standard slide agglutination serotyping (SAST)., Results: The results indicated that the M-PCR assay was high specificity and sensitivity and might be valuable for differential diagnosis of Haemophilus influenzae. The sensitivity of detection was 0.935 pg. 189 strains out of the 200 belonged to Haemophilus influenzae isolates, and one isolate was cap-type f. An agreement results were seen among the V and X factors grow requirement test, SAST and M-PCR methods., Conclusion: M-PCR method showed satisfactory sensitivity, specificity and stability for detecting and identifying Haemophilus influenzae, and could be used in clinic diagnosis, surveillance and rapid diagnosis for plague of Haemophilus influenzae.

Objective: To investigate the role of mitogen activated protein kinase (MAPK) pathway in the inflammatory response induced by nontypeable Haemophilus influenzae (NTHi)., Methods: NTHi was a clinical isolate identified by serum agglutination test and 16S rRNA gene sequencing. The peripheral monocytes isolated from adult healthy donors were divided into medium-treated group, NTHi-stimulated group, SB203580 (p38 MAPK inhibitor) -pretreated group and UO126 (p44/42 MAPK inhibitor) -pretreated group. Monocytes were co-cultured with NTHi and harvested 1 h and 4 h after stimulation. The phosphorylation of p38 and p44/42 MAPKs was detected by Western blot. The expression of toll-like receptor 4 (TLR4) was examined by flow cytometry 16 h after bacterial stimulation. Monocytes were preincubated with SB203580 or UO126 for 1 h and then stimulated with NTHi for 4 h and 16 h, respectively. The level of TNF-alpha in the supernatants was determined by Enzyme-linked immunosorbent assay (ELISA)., Results: The phosphorylation of p38 MAPK and p44/42 MAPK was rapidly induced by NTHi and continued for at least 4 h after stimulation. The expression of TLR4 on monocytes after NTHi stimulation was significantly up-regulated compared with the control group (11.8 +/- 1.6 vs 4.8 +/- 0.6, P < 0.05). The leve of TNF-alpha in the supernatants was increased 4 h and 16 h after bacterial stimulation compared with the control group (4 h : 16.4 +/- 5.3 vs 0.6 +/- 0.6, P < 0.01; 24 h : 30.2 +/- 10.7 vs 1.4 +/- 1.1, P < 0.01). SB203580 pretreatment decreased remarkably the TNF-alpha secretion from monocytes (P < 0.05) whereas UO126 had no significant effect on TNF-alpha level (P > 0.05)., Conclusion: TLR4 is probably involved in the inflammatory response of monocytes induced by NTHi whereas p38 MAPK is the key signal molecule in this inflammatory reaction.

Objective: The purpose of this study was to observe the bacterial infections of respiratory tract in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD)., Methods: 130 patients with AECOPD in outpatient department, emergency room or in wards were studied prospectively. Patients were divided into different groups according to both Anthonisen's classification and their lung function status. Sputum were cultured together with bacteria positive rate and types of AECOPD as well as the damage degree of lung function were analyzed., Results: Of 130 sputum samples, 50 showed positive through culture (38.5%) and 60 strains of pathogens were isolated. Predominant pathogens isolated would include Haemophilus parainfluenzae (20/60), Streptococcus pneumoniae (5/60) and Haemophilus influenzae (10/60). Positive rate of bacterial culture in type 1 AECOPD was 55.0%, higher than those of type 2 (38.3%) and type 3 (18.5%)(P = 0.01) and was increasing with the decrease of lung function of patients with AECOPD (P < 0.02)., Conclusion: Positive rate of bacterial culture in patients of type 1 AECOPD was the highest one. Haemophilus parainfluenzae was one of the most important pathogens in AECOPD. There seemed a correlation between positive result of bacterial culture and the severity of COPD.

Objective: To investigate the situation of antibiotic resistance of Streptococcus pneumoniae (Sp) and Hemophilus influenzae (Hi) clinical isolates from children in Guangzhou area., Methods: The authors cultured, isolated and identified the Sp and Hi strains from nasopharyngeal secretion of patients who visited Guangzhou Children's Hospital for upper respiratory tract infection between 2003 and 2004. K-B disc diffusion and E-test for antibiotic susceptibility were performed for these clinical isolates., Results: Totally 172 and 484 strains of Sp and Hi were respectively isolated from nasopharyngeal secretions in the hospital. For Sp strains, the rates of resistance to penicillin, amoxicillin/clavulanic acid, ceftriaxone, cefuroxime, cefaclor, erythromycin, tetracycline, chloramphenicol, sulfamethoxazole/trimethoprim (SMZ/TMP), clindamycin and ofloxacin were 32.0%, 11.1%, 32.6%, 18.1%, 39.5%, 82.6%, 78.5%, 24.4%, 87.2%, 69.2% and 3.1%, respectively. The penicillin non-susceptible Sp (PNSSP) isolates showed higher rates of resistance to other antimicrobial agents such as other beta-lactam antimicrobial agents, erythromycin, and SMZ/TMP than those of penicillin susceptible Sp (PSSP) isolates. More than 90% of PNSSP were multidrug resistant strains. The average rate of beta-lactamase production among 484 strains of Hi was 29.5% (143/484). For Hi isolates, the rates of resistance to ampicillin, amoxicillin/clavulanic acid, ceftriaxone, cefuroxime, cefaclor, SMZ/TMP, tetracycline, chloramphenicol, azithromycin, and ofloxacin were 40.1%, 3.4%, 4.1%, 1.9%, 5.6%, 56.2%, 52.1%, 17.4%, 2.1%, and 0.6%, respectively., Conclusion: The antimicrobials resistant Sp and Hi isolated from children with respiratory tract infection in the area have become a severe problem. The rate of resistance to penicillin of Sp had been decreased compared with the last three years, but the rate of resistance to ceftriaxone of Sp increased, and the multidrug resistance rates of PNSSP was rather high. PNSSP was characterized by a multidrug-resistance to erythromycin, tetracycline and SMZ/TMP. beta-lactamase production and ampicillin resistance among the Hi isolates from children in the area had increased generally during the period 2003 - 2004. The Hi isolates were more susceptible to the second and the third generation cephalosporins, amoxicillin/clavulanic acid and azithromycin.

Objective: To investigate the pathogenic causes of community-acquired pneumonia (CAP) in adult patients in China, the relation of previous antibiotic use and the Pneumonia Patient Outcome Research Team (PORT) classification to microbial etiology, and the prevalence of drug resistance of common CAP bacteria., Methods: A prospective study was performed on 665 consecutive adult patients with CAP at 12 centers in 7 Chinese cities during one year. The etiology of pneumonia was considered if one of the following criteria was met: (1) valid sputum sample yielding one or more predominant strains; (2) blood cultures yielding a bacterial pathogen; (3) seroconversion, a > or = 4-fold increase or decrease titers of antibodies to Mycoplasma pneumoniae, Chlamydia pneumoniae and Legionella pneumophila. Minimum inhibitory concentration (MIC) of respiratory tract isolates was determined using the agar dilution method., Results: Pathogens were identified in 324/610 patients (53.1%) with valid serum samples and sputum cultures as follows: Mycoplasma pneumoniae (126, 20.7%), Streptococcus pneumoniae (63, 10.3%), Haemophilus influenzae (56, 9.2%), Chlamydia pneumoniae (40, 6.6%), Klebsiella pneumoniae (37, 6.1%), Legionella pneumophila (31, 5.1%), Staphylococcus aureus (23, 3.8%), Escherichia coli (10, 1.6%), Moraxella catarrhalis (8, 1.3%), Pseudomonas aeruginosa (6, 1.0%). Of 195 patients with a bacterial pathogen, an atypical pathogen was identified in 62 (10.2%) cases. The non-susceptibility rate of Streptococcus pneumoniae to penicillin, azithromycin, and moxifloxacin was 20.3%, 75.4% and 4.3% respectively., Conclusions: Atypical pathogens have important role in CAP, with Mycoplasma pneumoniae being the most common pathogen, and mixed infection of atypical pathogens with bacteria was found in 10.2% of the cases. Streptococcus pneumoniae and Haemophilus influenzae remain the most important bacteria for CAP. More than 75.0% of Streptococcus pneumoniae was resistant to macrolides and 20.3% was resistant to penicillin.

Objective: To establish a method for rapid molecular detection of Streptococcus pneumoniae and Haemophilus influenzae in the early stage of infection., Methods: Specific DNA probes for Streptococcus pneumoniae and Haemophilus influenzae and 16 S rRNA universal probe of bacteria were synthesized by polymerase chain reaction (PCR) and labeled with biotin. The DNA of the bacteria, virus and fungi were hybridized with these probes respectively prior to application for examination of the clinical samples., Results: The DNA probes of 263, 351, and 370 bp were amplified by PCR. Streptococcus pneumoniae and Haemophilus influenzae reacted only with their corresponding probes, and no cross reaction of the bacterial universal probe with virus and fungi was noted. The method could detect bacterial DNA in as small amount as 1 ng. Of the 100 sputum specimens, 11 were found to be positive for Streptococcus pneumoniae and 8 for Haemophilus influenzae, with a positivity rate greater than that by sputum culture., Conclusion: DNA probe detection is simple, rapid, and specific for clinical examination of Streptococcus pneumoniae and Haemophilus influenzae.

Objective: Haemophilus (H.) influenzae is a gram-negative bacillus that is a common commensal organism of the human upper respiratory tract and an important cause of human diseases such as pneumonia, meningitis, septicemia, epiglottitis and cellulitis. Strains of H. influenzae are classified according to their capsular polysaccharide. There are six serotypes, designated as a through f. In addition, there are nonencapsulated strains. Although the type of infectious diseases caused by H. influenzae has changed considerably in recent years because of the widespread and routine immunization of children against type b H. influenzae (Hib), Hib remains an important pathogen. Ampicillin is the drug of choice for treating many infections caused by H. influenzae, but its usefulness has been compromised by the increasing prevalence of ampicillin-resistant strains. The continued monitoring of resistant strains by using genotyping methods may provide insights into the epidemiology of transmission. A molecular epidemiological study of ampicillin-resistant H. influenzae derived from nasopharyngeal swabs specimens of children less than 5 years of age with respiratory tract infection were investigated in this study., Methods: A total of 899 isolates were collected from Beijing, Shanghai, and Guangzhou during 2000-2003. Susceptibility to ampicillin was determined by using E-test. Ampicillin-resistant H. influenzae strains were selected according to National Committee for Clinical Laboratory Standards (NCCLS) 2002 breakpoints. Nested PCR method with primers specific for bexA gene and b capsulate type-specific gene was established. Genotyping by pulsed-field gel electrophoresis (PFGE) and multiplex PCR assay was performed for all ampicillin-resistant H. influenzae strains., Results: Seventy-four ampicillin-resistant H. influenzae strains were obtained. Two strains were positive by nested PCR, characterized as b genotype. The incidence of Hib in ampicillin-resistant H. influenzae strains was 2.7%; 38 genotypes were detected by PFGE. Detection of five types strains of clonal dissemination by PFGE accounted for 55.4% in all ampicillin-resistant H. influenzae strains. Among them eighteen H. influenzae strains belonged to one type, accounted for 24.3% in all ampicillin-resistant H. influenzae strains. Thirty one genotypes were identified by multiplex PCR assay for ampicillin-resistant H. influenzae. The identity ratio of PFGE and multiplex PCR was 63.5%., Conclusion: In Beijing, Shanghai and Guangzhou areas 55.4% of ampicillin-resistant H. influenzae strains had clonal dissemination during the 4 years.

Objective: To investigate the serotypes and antibiotics-resistance patterns of Haemophilus influenzae isolated from children in Hangzhou., Methods: Isolates were identified with api-NH card. Serotypes were determined with slide agglutination method. The sensitivities of 13 antibiotics against 247 strains of Haemophilus influenzae were determined in vitro with Kirby-Bauer diffusion methods and MICs of ampicillin were determined with E-test. Nitrocefin test was used to detect beta-lactamase., Results: Of the 247 strains isolated from children during the period from August 2001 to July 2002, 153 strains were non-typable, while 94 strains (38.1%) were typable and 90.4% and 1.1% of them belonged to type d and type b, respectively. Higher incidence of typable Haemophilus influenzae was found in male than in female children and the difference was significant (chi(2) = 5.30, P < 0.05), while between upper and lower respiratory tract infected children the difference was not statistically significant (chi(2) = 3.60, P > 0.05). Forty-one isolates (16.6%) were beta-lactamase-positive and 14 strains could not grow on medium in antibiotics sensitivity test. Of all 233 isolates tested successfully, 85.4% were susceptible to ampicillin, and the sensitivity rate to cefaclor, ceftriaxone, cefotaxime, imipenem, rifampin, clarithromycin, and chloramphenicol were as high as 98.7%, 99.6%, 99.6%, 99.6%, 98.7%, 91.0%, and 90.6%, respectively. All strains were sensitive to amoxicillin/clavulanic acid, ampicillin/sulbactan and ofloxacin, while 107 strains (45.9%) were resistant to trimethoprim-sulfamethoxazole, followed by that of tetracycline (14.6%). Resistance to ampicillin and trimethoprim-sulfamethoxazole in typable isolates was statistically significantly higher than in non-typable strains. Twenty-six strains (10.5%) were multi-resistant isolates and the multi-resistance rate in beta-lactamase-positive strains were significantly higher than that in beta-lactamase-negative strains (chi(c)(2) = 146.8, P < 0.001)., Conclusion: Non-typable Haemophilus influenzae was the most common type in clinical strains isolated from children in Hangzhou, while type d was the overwhelming type and type b was uncommon in typable isolates. Incidence of typable isolates was higher in male than in female children, and it was apt to intergrow with other species of pathogenic bacteria. The proportion of beta-lactamase-positive strains was not high and ampicillin or other beta-lactam actibiotics were still the treatment of choice for infections with Haemophilus influenzae.

Objective: To investigate the situation of antibiotic resistance of Haemophilus influenzae isolates from Chinese children., Methods: Eight hundred and ninety-eight strains of H. influenzae isolated from randomly selected pediatric out-patients in Beijing, Shanghai and Guangzhou 2000 approximately 2002 underwent determination of antibiotic susceptibility by E test MIC method for beta-lactam antibiotics (ampicillin, amoxicillin/clavulanic acid, ceftriaxone, cefuroxime, and cefaclor) and KB disc diffusion method for chloramphenicol, tetracycline, sulfamethoxazole/trimethoprim (SMZ/TMP), azithromycin, and ciprofloxacin., Results: The average rate of beta-lactamase production among these isolates was 12%. The MIC50 and MIC90 of ampicillin were 0.25 microg/ml and 4 microg/ml respectively for the 898 isolates, 88% of the isolates were susceptible to ampicillin and 10.6% was resistant. There was no beta-lactamase negative strains among the ampicillin intermediately-susceptible and resistant strains. All the isolates were susceptible to amoxicillin/clavulanic acid, ceftriaxone, cefuroxime and azithromycin. 96.1% of the H. influenzae isolates generally remained susceptible to cefaclor with a MIC50 of 1.5 microg/ml and a MIC90 of 3 microg/ml, and 99% of the isolates were susceptible to ciprofloxacin. The susceptibility rate to tetracycline of the isolates from Beijing and Shanghai areas were 57% and 61% respectively, both lower than the susceptibility rates of the isolates from Guangzhou (81%), while the resistant rate to SMZ/TMP of the isolates from Beijing was 35%, lower than those of the isolates from Guangzhou (47%) and Shanghai (54%). The resistant rate to ampicillin was 7.7% in 2000 and was increased to 14.5% in 2002. 34.5% of all the isolates were susceptible to 8 antimicrobial agents while 12.8% was multi-drug resistant. 58.5% of the isolates were distributed in five major antimicrobial resistance profiles in which SMZ/TMP resistance (29.8%) was the most prevalent, followed by SMZ/TMP and tetracycline combined resistance (12.5%) and tetracycline resistance (9.4). The ampicillin non-susceptible isolates had higher resistant rates to cefaclor (23.5%), tetracycline (63.3%), SMZ/TMP (74.5%) and chloramphenicol (63.3%) than the ampicillin susceptible strains (1.6%, 51.4%, 11.1% and 4.9% respectively)., Conclusion: Beta-lactamase production and ampicillin resistance among the isolates from Chinese children are increasing generally during the period 2000 approximately 2002. There is variation of resistance among different regions. There are strong correlations between ampicillin resistance and resistance to cefaclor, chloramphenicol, and tetracycline among the H. Influenzae isolates.

Objective: To investigate antimicrobial resistance of common community respiratory pathogens isolated in China, 2002 - 2003., Methods: 779 strains of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Group A beta-haemolytic Streptococci and oxacillin-susceptible Staphylococcus aureus (MSSA) were isolated from patients with community-acquired respiratory tract infections at 5 hospitals in China from April 2002 to 2003. Meanwhile, 185 strains of S. pneumoniae, H. influenzae and M. catarrhalis were isolated from nasopharynx swabs at 2 day-care centers in Beijing. Agar dilution method was used to determine the minimal inhibitory concentration (MICs) of cefprozil and other 9 antibiotics against these strains., Results: The prevalence of penicillin-intermediate S. pneumoniae (PISP) was 23.9% and that of penicillin-resistant S. pneumoniae (PRSP) was 22.7% at 5 cities in China. The prevalence of PISP were 44.1% in Hangzhou, 26.2% in Wuhan, 21.5% in Shenyang, 20.8% in Shanghai, 18.5% in Beijing, and 12.7% at day-care centers in Beijing;the prevalance of PRSP were 34.9% in day-care centers, 31.9% in Shanghai, 27.9% in Wuhan, 22.1% in Hangzhou, 13.8% in Shenyang and 8.6% in Beijing. The susceptible rate of levofloxacin in S. pneumoniae was 96.3%. 9.5% of H. influenzae and 87.4% of M. catarrhalis produced beta-lactamases. The susceptibility of amoxicillin/clavulanate, cefaclor, cefprozil, cefuroxime, ceftriaxone, azithromycin, and levofloxain in these two species ranged from 96.4% to 100%. The resistance rate of azithromycin in S. pneumoniae was higher than 60%. Cefprozil MICs against PISP, Group A beta-haemolytic Streptococci and MSSA were 4 - 16 fold lower than cefaclor., Conclusions: Antimicrobial resistance in respiratory pathogens, especially S. pneumoniae is increasing. It brings concerns that high macrolide resistance was found in gram-positive cocci. Cefprozil was more active than cefaclor against respiratory pathogens.

Objective: To study the status of oral pharyngeal carriage and characteristics of Haemophilus influenzae (Hi) in healthy preschool children in Fuzhou., Methods: Six hundred and three healthy children in two representative kindergartens in Fuzhou were studied as research subjects, and the rates of oral pharyngeal carriage of Hi were studied in four seasons. All Hi strains were serotyped and biotyped., Results: The oral pharyngeal carriage of Hi in day care nursery healthy children were 36.7% in winter, 18.0% in autumn, 12.4% in summer and 10.9% in spring respectively. Serotype Hib was preponderant in autumn (6.9%). In winter, the carriage rates of NTHi and Hib were 17.1%, 5.4% respectively. The carriage rates of other serotypes were low. Biotype VII and VIII were preponderant in autumn, spring and summer but biotype VII and VIII were decreasing evidently in winter., Conclusion: There was evident seasonal difference in the rates of oral pharyngeal carriage and type of Hi in healthy preschool children. The carriage rate of Hi strains was high in autumn and winter. Results suggested that while the inoculation of Hib-binding bacterial vaccine was expanded the study on new bacterial vaccine of Hi still needs to be augmented.

Objective: To improve the positive rate of Hi isolation and to study the epidemiology, antibiotic sensitivity and clinical characteristics of the lower respiratory tract infection by Hi., Methods: Modified Columbia chocolate agar(ICCA) was compared with blood agar staphy stick (BASS) for the primary isolation of Hi from sputa. The sensitivities of 20 antibiotics to Hi were determined in vitro by KB method and MICs of 12 antibiotics were determined by broth microdilution method. The clinical characteristics of 92 cases with lower respiratory tract infection by Hi were analyzed., Results: The isolation rate of Hi by ICCA was 20%, which was higher than 13% of BASS(P < 0.01). The third generation cephalosporins and the quinolones were most active against Hi. The resistant rate against Hi of ampicillin was 21%, however, that of the third generation cephalosporins was 45%-49%. 67(73%) of 92 cases were bronchopneumonia., Conclusions: The isolation rate of Hi could be improved by ICCA. The clinical characteristic of lower respiratory tract infection by Hi was not specific. There has been a steady increase of antibiotic resistance during these years.

Objective: To understand Haemophilus influenzae special protein and to help for preparing Haemophilus influenzae Vaccine., Methods: Proteins from isolates of Haemophilus influenzae were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)., Results: 23 isolates were from nasopharyngeal secretions of children with pneumonia and 33 from pharyx swab of healthy children. Conventional tests showed that 79% of fifty-six strains of Haemophilus influenzae were non-serotypable and all belonged to one of eight biotypes. The common biotypes were II (48%). All strains contained more than 10 proteins with molecular weights of 96,000, 86,000, 55,000, 51,000, 46,000, 40,000, 39,000, 31,000, 29,000, 25,000, and 16,000. Among them, three were major proteins (31,000, 51,000 and 96,000) and different proteins were mainly between peptide 31,000 and 51,000. A possible association between biotype and protein was unclear., Conclusion: Analysis of protein of Haemophilus influenzae is helpful for epidemiological study of non-serotypable Haemophilus influenzae and making Haemophilus influenzae vaccine.

Results of quantitative culture of pathogenic bacteria in nasopharyngeal secretions of 154 cases of hospitalized children with bacterial pneumonia demonstrated that the highest culture rates were Haemophilus influenzae (39.0%) and streptococcus pneumoniae (20.8%). Recovery rate of H. influenzae and Str. pneumoniae among children of various age groups demonstrated that the smaller the age, the higher the recovery rate. The recovery rates of these two bacteria were highest in December and in November, respectively.

One hundred and fifteen healthy children in 2 kindergartens of Beijing City were enrolled in a study for carrier state of Haemophilus influenzae (HI) in pharynx. Nontypable HI flora was found in 32.2% (37/115) in this group. There were no significant differences of carrier state in sex, age, and season in these children. Antibiotic sensitivity test showed that some HI strains isolated were resistant to ampicillin and tetracycline (5/34 vs 4/34), most strains resistant to SMZ Co (21/34).