突变敏感性分子开关检测肺炎支原体对大环内酯类抗生素的耐药性研究

目的 应用突变敏感性分子开关检测肺炎支原体对大环内酯类抗生素的耐药性。方法 采用微量稀释法检测5种常用大环内酯类抗生素对40株Mp临床分离株的药物敏感性;建立高保真聚合酶和3'硫化修饰引物的分子开关,用分子开关进行Mp临床分离株的PCR扩增,检测其是否存在Mp 23S rRNA 2063、2064和2617 3个热点突变,并通过基因测序进一步确定是否存在点突变,分析点突变与大环内酯类抗生素敏感性之间的关系。结果 5种大环内酯类抗生素中,Mp对14元环的红霉素和克拉霉素耐药程度最高,其MIC≥128 mg/L;对15元环的大环内酯类抗生素阿奇霉素和交沙霉素相对敏感,其中交沙霉素抗Mp活性最高,其MIC≤4 mg/L。用高保真聚合酶和3'硫化修饰引物的分子开关行PCR扩增,检测出35株发生了2063位点基因突变,3株发生2064位点基因突变,未检测出2617位点突变。用基因测序检测到35株Mp发生A2063G的突变,3株发生A2064G的突变,未检测到2617位点突变,与分子开关的检测结果一致,并且2063、2064位点突变Mp株均对大环内酯类药物高度耐药。结论 分子开关可识别23S rRNA基因突变,可用于分析Mp对大环内酯类抗生素的敏感性。     

Characteristics of hospitalized children infected with macrolide-resistant Mycoplasma pneumoniae

BackgroundThe aim of this study was to clarify retrospectively the characteristics of children hospitalized for respiratory tract infection caused by macrolide-resistant Mycoplasma pneumoniae (M. pneumoniae).MethodsChildren who were hospitalized for respiratory tract infection due to M. pneumoniae were enrolled in this study. The diagnosis of M. pneumoniae infection was made on the grounds of polymerase chain reaction results.ResultsThirty-three children were hospitalized due to lower respiratory tract infection with M. pneumoniae. Of the 33 children, 31 (median age five years) were identified as being infected with macrolide-resistant M. pneumoniae (A2063G:30, A2064G:1) by sequence analysis. Of the 31 children infected with macrolide-resistant M. pneumoniae, 21 (68%) had received 14- or 15-membered macrolide antibiotics and four (13%) had received minocycline before hospitalization. During hospitalization, minocycline was administered to 16 (52%) of the 31 children infected with macrolide-resistant M. pneumoniae. Of the 20 children infected with macrolide-resistant M. pneumoniae under eight years of age, six (30%) were treated with minocycline during hospitalization. The difference in total febrile days between children receiving minocycline treatment before hospitalization and children not receiving minocycline treatment was three days.ConclusionsThe majority of hospitalized children with respiratory tract infection due to macrolide-resistant M. pneumoniae infection was of preschool age and had received 14- or 15-membered macrolide antibiotics before hospitalization. Because macrolide-resistant M. pneumoniae is widespread in Japan, the administration of minocycline as a second-line antibiotic in children under eight years of age cannot be withheld when clinical symptoms do not improve with macrolide antibiotics.     

Macrolide resistance and detection in Mycoplasma pneumoniae at Kansai Medical University Hirakata Hospital

Mycoplasma pneumoniae causes bronchitis and pneumonia predominantly in subjects 5 to 20 years old. M. pneumoniae is detected by measuring specific antibodies and/or isolating the microorganism, but the frequency of false-positive/negative results, and the culture time required until isolation pose problems. We detected M. pneumoniae using real-time PCR with clinical specimens. We also determined the drug sensitivity of isolated M. pneumoniae and searched for the gene mutation responsible for macrolide resistance. In 275 cases of suspected M. pneumoniae infection, positive cases in real-time PCR numbered 40 (14.5%). Of these, 16 showed positive culture (5.8%). Of these 16, A2063G point mutation that causes macrolide resistance was found in 12. Drug sensitivity testing showed resistance to clarithromycin (MIC> or =64 microg/ml) in 11 and susceptibility in 4 (MIC 0.0039 microg/ml). The clarithromycin resistance ratio was 75%. Growth was insufficient for testing in 1 case. M. pneumoniae was susceptible to minocycline and all quinolone drugs. M. pneumoniae detection using real-time PCR proved much more sensitive than conventional culture. Macrolide resistance results correlated well with genomic mutation. Our study's macrolide resistance ratio was high at 75% possibly due to a restricted subject population that had been administered macrolide drugs elsewhere but with an unsatisfactory outcome. The increasing number of reports on macrolide resistance requires that we monitor drug resistance trends, particularly among macrolide derivatives.     

Chlamydia pneumoniae infections in patients with community-acquired pneumonia in Slovenia

It is well known that Chlamydia pneumoniae is an important respiratory pathogen. In this study, the prevalence of specific antibodies to C. pneumoniae in hospitalized patients with community-acquired pneumonia (943 adult females, 990 adult males and 185 children) was evaluated over a period of 7 y (1993-99). Two serum samples were obtained from all of the patients: 1 on admission and the other 3 weeks later. The specimens were tested for C. pneumoniae IgG, IgM and IgA antibodies by means of a microimmunofluorescence test. Acute infection with C. pneumoniae was determined in 9.4% of females and 13.1% of males. In children and adolescent patients, the microimmunofluorescence test showed recent infection in 8.6% of cases, with the highest prevalence occurring in the 11-15 y age group. The highest prevalence of C. pneumoniae pneumonia was found in 1995 and 1999: 15.4% and 13.6% respectively. The results obtained showed that C. pneumoniae is persistently present in the population of Slovenia.     

Mycoplasma pneumoniae infection in hospitalized children with acute pneumonia under the Mycoplasma epidemic

Since October 2000, Mycoplasma pneumonia has been a recurring epidemic in Japan. To become clear the importance of Mycoplasma pneumoniae infection in children, we investigated cross-sectionally M. pneumoniae infection by serology in the hospitalized children age under seven years with acute pneumonia retrospectively reviewing pediatric patients of the four studies about lower respiratory tract infection which we had been treated during 2001 to 2003. Firstly, we found M. pneumoniae infection in 75 patients (33.8%) among a total of 222 patients with asthma exacerbation and acute pneumonia in 2001. Second, we had evaluated a total of 46 hospitalized children with acute pneumonia for M. pneumoniae infection in November 2002 and 18 patients (39.1%) were found. Thirdly, we found M. pneumoniae infection in 8 patients (34.8%) among 23 patients with respiratory syncitial virus and acute pneumonia age under two years during October 2002 to April 2003. Fourthly, we found M. pneumoniae infection in 19 patients (35.8%) among 53 patients with asthma exacerbation and acute pneumonia during January from June in 2003. Even only among the patients age under two years M. pneumoniae infection was found to be 24.3% (16/70), 27.8% (5/8), 34.8% (8/23) and 33.3% (7/21), respectively. These findings demonstrate that M. pneumoniae is common pathogen of acute pneumonia even in infants and young children under Mycoplasma epidemic. Not only typical bacteria and but also M. pneumoniae should be considered as important pathogens in the treatment of acute pneumonia in infants and young children under Mycoplasma epidemic.     

Atypical pathogens in adult patients admitted with community-acquired pneumonia in Korea

This study examined the prevalence of atypical pathogens causing community-acquired pneumonia (CAP) in Korea. We collected sera and clinical data for a period of 1 year for the adult patients consecutively admitted to Chunchon Sacred Heart Hospital with CAP. The diagnosis was made using serologic methods to detect antibodies for Mycoplasma pneumoniae, Chlamydia pneumoniae, Legionella spp., Chlamydia psittaci, and Coxiella burnetii. Among 81 recruited patients, C. pneumoniae (n = 10, 12.3%) was the leading cause of illness, followed by M. pneumoniae (n = 7, 8.6%). One case of C. burnetii pneumonia was detected, but there were no cases of Legionella spp. or C. psittaci. Three cases of C. pneumoniae pneumonia were co-infected with either M. pneumoniae or C. burnetii. There was no significant difference between atypical pneumonia and non-diagnosed pneumonia in terms of clinical manifestations. In conclusion, of the atypical pathogens causing CAP, C. pneumoniae and M. pneumoniae appear to be the important etiologic pathogens in Korea.     

Predictive factors of etiologic agents of community-acquired pneumonia presenting at a district general hospital]

Community-acquired pneumonia is one of the major respiratory diseases causing hospital admission in previously healthy patients. Prompt and appropriate antibiotic selection is essential for recovery. The authors tried to determine the distribution of the etiologic agents of community-acquired pneumonias and to analyze predictive factors. Out of 188 cases of community-acquired pneumonia presenting to our hospital, etiologic agents were determined in 106 cases (56%). Twenty-nine cases were due to Streptococcus pneumoniae, 27 cases due to Mycoplasma, 17 cases due to Haemophilus influenzae and 21 cases due to Mycobacterium tuberculosis. M. tuberculosis was the cause in 11% of all cases and the importance of pulmonary tuberculosis must be emphasized as a community-acquired pneumonia. Out of 58 cases under 50 years old, Mycoplasma pneumoniae was the etiologic agent in 23 cases (40%) and S. pneumoniae in 7 cases (12%). Out of 62 cases not less than 70 years old. M. tuberculosis was the most common etiologic agent (15 cases, 24%). S. pneumoniae followed, being causative in 13 cases (21%). M. tuberculosis was the cause in 10 cases out of 31 cases who did not complain of fever at presentation. In 86 cases who did not show leukocytosis on admission, 21 cases were due to Mycoplasma (24%) and 15 cases were due to M. tuberculosis (17%). In particular 17 cases were due to Mycoplasma among 28 cases under 50 years old without leukocytosis (61%), and 11 cases were due to M. tuberculosis in the 27 cases no less than 70 years old without leukocytosis (41%).(ABSTRACT TRUNCATED AT 250 WORDS)     

Epidemiology of severe pneumonia caused by Legionella longbeachae, Mycoplasma pneumoniae, and Chlamydia pneumoniae: 1-year, population-based surveillance for severe pneumonia in Thailand.

BACKGROUND: Legionella species, Mycoplasma pneumoniae, and Chlamydia pneumoniae are recognized as important causes of pneumonia in high-income countries, but their significance in middle-income countries, such as Thailand, is unknown. METHODS: Population-based surveillance identified inpatient 3489 cases of clinically-defined pneumonia in a rural Thai province for 1 year. Patients who had a chest radiograph performed (for 2059 cases of pneumonia) were enrolled in an etiology study (which included 755 cases of pneumonia among 738 patients). Paired serum, nasopharyngeal swab, and urine specimens were obtained for diagnostic immunologic and molecular tests. Patients aged <18 years were not systematically tested for Legionella species. We report a lower limit of incidence (observed incidence) and an upper limit extrapolated to persons not tested or not enrolled in the study. RESULTS: The incidence of pneumonia due to Legionella longbeachae requiring hospitalization was 5-29 cases per 100,000 population. No case of Legionella pneumophila pneumonia was observed. The definite C. pneumoniae pneumonia incidence was 3-23 cases per 100,000 population; rates were highest among patients aged <1 year (18-166 cases per 100,000 population) and those aged >or=70 years (23-201 cases per 100,000 population). M. pneumoniae pneumonia had a similar age distribution, with an overall incidence of 6-44 cases per 100,000 population. These pathogens were associated with 15% of all cases of pneumonia. A nonsignificantly higher proportion of patients with pneumonia associated with L. longbeachae, compared with patients with pneumonia associated with M. pneumoniae or C. pneumoniae, required supplemental oxygen or mechanical ventilation (45% vs. 18%; P<.1). Among patients with atypical pneumonia, only 15% received antibiotics with activity against the associated pathogen. CONCLUSION: M. pneumoniae, C. pneumoniae, and L. longbeachae, but not L. pneumophila, are frequently associated with severe pneumonia in rural Thailand. Few patients receive antibiotics that cover atypical pathogens.     

Chlamydia pneumoniae infection and Mycoplasma pneumoniae infection in pediatric patients

We evaluated a total of 1104 pediatric patients with acute lower respiratory tract infection for C. pneumoniae infection and M. pneumoniae infection by serology during July 1995 to December 1998. A microimmunofluorescence test was used for diagnosis of C. pneumoniae infection and a high density particle agglutination test for that of M. pneumoniae infection. Acute C. pneumoniae infection was found in 149 patients (13.5%), acute M. pneumoniae infection in 118 patients (10.7%), and dual infection in 27 patients (2.4%). Among 305 patients with pneumonia, M. pneumoniae infection (83 patients, 27.2%) was more common than C. pneumoniae infection (47 patients, 15.4%). However among 799 patients with bronchitis. C. pneumoniae infection (102 patients, 12.8%) was more common than M. pneumoniae infection (35 patients, 4.4%). Patients with C. pneumoniae infection were more younger and more frequently wheezing than patients with M. pneumoniae infection. These findings demonstrate that C. pneumoniae infection in very common pathogen of pediatric lower respiratory tract infection as M. pneumoniae infection in Japan.     

Mycoplasma pneumoniae and Chlamydophila pneumoniae in children with community-acquired pneumonia in Thailand.

BACKGROUND: The prevalence of community-acquired pneumonia (CAP) caused by atypical pathogens in Thai children is unknown. OBJECTIVE: To examine the prevalence of Mycoplasma pneumoniae and Chlamydophila pneumoniae infections in paediatric patients (aged 2-15 years) with CAP in three academic hospitals using standardised laboratory techniques. The characteristics of atypical pneumonia were also compared with other causes of CAP. METHODS: Diagnosis of current infection was based on a four-fold or more rise in antibody serum samples or persistently high antibody titres together with the presence of mycoplasmal or chlamydial DNA in secretions. RESULTS: Of 245 patients with CAP, 17.5% of cases were caused by atypical pathogens (M. pneumoniae 14.3%, C. pneumoniae 2.8% and co-infection 0.4%). We also found atypical pathogens in young children aged 2-5 years. The clinical and laboratory findings did not distinguish atypical pneumonia from other CAPs. Segmental or lobar consolidation on chest X-rays was more common in atypical pneumonia, while dyspnoea was more prominent in other CAPs. CONCLUSION: Our data show a high prevalence of M. pneumoniae and C. pneumoniae in Thai children with CAP, including in children aged 2-5 years.     

Community-acquired Chlamydia pneumoniae pneumonia in Japan: a prospective multicenter community-acquired pneumonia study

OBJECTIVE: To investigate the clinical features of Chlamydia pneumoniae pneumonia in Japan and to evaluate the newly created Japanese community-acquired pneumonia (CAP) guidelines. PATIENTS AND METHODS: A multicenter CAP surveillance study was carried out in 20 hospitals between December 1999 and March 2000. The diagnosis of C. pneumoniae infection was based on isolation in cell culture, the polymerase chain reaction and serologic testing of antibodies by the microimmunofluorescence test. RESULTS: Among 232 CAP cases, C. pneumoniae was identified as the etiologic agent in 15 cases (6.5%). C. pneumoniae was the only pathogen identified in nine of these cases, while one or more additional etiological agents were found in the other six cases. Of the present and previously reported single agent C. pneumoniae pneumonia cases, about 50% were more than 60 years old and had underlying diseases. A relatively slow pulse rate in relation to fever was not seen in these patients. The mean WBC count of all patients was normal. No patient required respiratory support or admission to an intensive care unit and no deaths occurred among these patients. CONCLUSION: The clinical pictures of C. pneumoniae pneumonia as a single agent were mild to moderate and were remarkably different from those of cases of C. pneumoniae pneumonia concomitant with other bacteria. If the patient is less than 60 years old and some guideline headings are excluded, we think it would be possible to distinguish between C. pneumoniae and bacterial pneumonia.     

Prevalence of Mycoplasma and Chlamydia pneumonia in severe community-acquired pneumonia among hospitalized children in Thailand

Pneumonia is the leading cause of pediatric morbidity and mortality worldwide, and Mycoplasma pneumoniae and Chlamydia pneumoniae are the two most common atypical pathogens. This study was designed to determine the prevalence and clinical impact of mycoplasma and chlamydia pneumonia in children hospitalized with severe pneumonia. Children 1 month-15 years old with a diagnosis of severe pneumonia (WHO criteria) were recruited between March 2005 and March 2006. Serologic studies were performed for anti-M. pneumoniae and anti-C. pneumoniae IgG/M on admission and 2-4 weeks afterward using ELISA. Of 52 patients, 13 (25%) were positive for Mycoplasma, 8 (15%) were positive for Chlamydia, 4 (7.6%) were positive for a mixed infection and 27 (52%) were negative. The subjects' mean age was 23.8+/-4.1 months. The mean of initial oxygen saturation on admission was 87.5+/-1.2%. Fever and prolonged cough were the leading symptoms. The mean of hospitalization was 18.8+/-2.6 days, chlamydia pneumonia had the longest duration, 30+/-10.2 days and 13/52 (25%) study subjects developed respiratory failure. Only 10% were treated with adequate antibiotic prior to serologic results. There was one mortality (1/52, 2%). Our study suggests that mycoplasma and chlamydia infections are commonly found among children hospitalized with severe pneumonia. Coverage with an appropriate antibiotic should be considered to hasten recovery.     

Isolation of Mycoplasma pneumoniae from children with lower-respiratory-tract infections

The prevalence and clinical pictures of Mycoplasma pneumoniae infections among children were studied using culture and serological techniques. The isolation rate was 22% (195 of 885) in pneumonic patients and 11% (66 of 600) in non-pneumonic patients. In patients three years of age or less, M. pneumoniae was isolated at the same rate from febrile and afebrile cases and from wheezy and non-wheezy cases. In older patients, however, M. pneumoniae was frequently isolated from febrile but non-wheezy cases. A peak in the number of the positive isolates was found in patients who were four years old. The peak number of M. pneumoniae infections at age four was confirmed serologically. This peak was in patients who were younger than those previously reported.     

Investigation of Streptococcus pneumoniae and Haemophilus influenzae isolated from pediatric outpatients nationwide with a respiratory tract infection at the first consultation (2002-2003)--with special reference to the results of nasopharyngeal culture in pediatric patients with no previous history of antibacterial drug administration

We previously reported that penicillin-resistant Streptococcus pneumoniae (PRSP) and beta-lactamase-nonproducing ampicillin-resistant (BLNAR) were detected at a frequency of 27% and 35% in 468 strains of Streptococcus pneumoniae and 557 strains of Haemophilus influenzae isolated from pediatric patients diagnosed with respiratory infection in 20 pediatric outpatient facilities throughout Japan between November 2002 and June 2003. Here, we have added additional considerations regarding results of nasopharyngeal culture from 558 pediatric patients diagnosed with pneumonia, bronchitis, or otitis media and having no previous history of antibacterial drug administration. No significant difference was seen in the detection of S. pneumoniae or H. influenzae between nasal and oral specimens, or between patients with pneumonia, bronchitis, and otitis media. The detection of S. pneumoniae in pediatric patients 4 years old was significantly higher, however than that in pediatric patients 5 years old. The detection of H. influenzae in pediatric patients with a history of attending group childcare facilities was significantly higher than that in pediatric patients with no such history. No significant differences were seen among groups in the percentage of PSRP and BLNAR isolated among S. pneumoniae and H. influenzae strains. Nasopharyngeal culture of pediatric patients with respiratory infection yielded a higher frequency of S. pneumoniae in younger than older patients and a higher frequency of H. influenzae in pediatric patients with a history of attending group childcare facilities. The detection of resistant bacteria was considered related to other factors, such as the type of antibacterial drugs used, that are not discussed here.     

Diagnostic utility of the polymerase chain reaction for the diagnosis of Mycoplasma pneumoniae in elderly patients with community-acquired pneumonia

Mycoplasma pneumoniae is a common cause of community-acquired pneumonia (CAP) in children and young adults, but limited information about its prevalence in the elderly is available. The polymerase chain reaction (PCR) with primers targeting the cytadhesine P1 gene and the 16S rRNA gene was analyzed for detecting M. pneumoniae in throat washings of 84 patients, aged 60-96 years, with clinical diagnosis of CAP, from September 2002 through August 2004, in Santiago, Chile. PCR results were compared with serology performed by indirect immunofluorescence (IFI). Specimens from 11 of 84 patients (13.1%) were positive for M. pneumoniae by any test. The IFI test was positive in 8 (72.7%) patients and PCR in 7 (63.6%) cases. The acute phase sera allowed diagnosis of M. pneumoniae in 5 of 11 patients (45.4%), 4 of them showing an IgM response. PCR was negative in 4 patients with positive serology and 3 patients were positive only by PCR. The two PCR primers showed 100% correlation, and a similar sensitivity; no inhibitory specimens for PCR were detected. In conclusion, M. pneumoniae should be considered as a potential etiologic agent of CAP in the elderly. Its detection must be performed by a combination of PCR and serology.     

Epidemiological studies on pulmonary pathogens in HIV-positive and -negative subjects with or without community-acquired pneumonia with special emphasis on Mycoplasma pneumoniae

The prevalence of Mycoplasma pneumoniae among HIV-positive patients with community-acquired pneumonia (CAP) remains unclear. We investigated 300 HIV-positive adults (200 with CAP and 100 with no respiratory illness) and 75 HIV-negative adults with CAP for the prevalence of respiratory pathogens using culture and serology. A growth inhibition test was employed to confirm the isolates of M. pneumoniae using species-specific typing sera. The prevalence of M. pneumoniae in HIV-positive subjects was 17% by induced sputum and 11.3% by throat swab culture. The seroprevalence of anti-M. pneumoniae IgM was 11.7% by ELISA and 14.3% by the gelatin microparticle agglutination test. The prevalence of M. pneumoniae among HIV-negative cases was relatively low. Streptococcus pneumoniae was predominant (28%) among subjects with lower respiratory disease, whereas Staphylococcus aureus (15%) was common among upper respiratory symptomatic cases. Rales (P=0.001), pharyngeal erythema (P=0.02), cervical adenopathy (P=0.004), skin rash (P=0.001), and crepitations (P=0.001) were each significantly related to M. pneumoniae positivity. Statistical significance was observed in relation to total lymphocyte count (P=0.02) and erythrocyte sedimentation rate (P=0.04), as well as M. pneumoniae positivity. This study shows that the prevalence of M. pneumoniae in HIV-positive subjects is comparatively higher than in HIV-negative subjects with pulmonary symptoms, and concords with previous pilot studies carried out in Chennai, South India.     

肺炎支原体对大环内酯类抗生素耐药机制的研究近况

肺炎支原体是社区获得性肺炎的主要病原体。大环内酯类抗菌药物是治疗儿童肺炎支原体感染的首选药物。近年来我国耐大环内酯肺炎支原体比例有所下降,但仍处于高水平。耐药肺炎支原体感染造成患者发热时间、住院时间延长,并有更高的并发症发生率和抗生素治疗方案改变率,因此对肺炎支原体耐药机制的研究还需进一步深入。肺炎支原体对大环内酯类抗生素耐药机制主要与抗生素作用靶点突变、抗生素作用靶点修饰、药物主动外排、酶性失活有关。     

Clinical comparison of Chlamydia pneumoniae pneumonia, ornithosis, and Mycoplasma pneumoniae pneumonia]

To elucidate the differences between the clinical aspects of Chlamydia pneumoniae (C. pn) pneumonia and those of two other atypical pneumonias, Chlamydia psittaci (C. ps) pneumonia and Mycoplasma pneumoniae (M. pn) pneumonia, we analyzed the symptoms and laboratory data on the cases of these three types of pneumonia: 46 cases of C. pn pneumonia, 39 cases of C. ps pneumonia, and 131 cases of M. pn pneumonia. C. pn pneumonia was significantly more frequent among the elderly (mean 70 +/- 16 years, p < 0.01) and patients were significantly more likely to be male (76%, p < 0.05). A white blood cell count of over 10,000 was seen in 46% of C. pn pneumonia cases, a higher proportion than those of C. ps pneumonia (15%, p = 0.03) or M. pn pneumonia (18%, p = 0.006) cases. The proportions of patients with these infections who had an elevated GOT or GPT were not significantly different. Maximum body temperature was higher in M. pn pneumonia than in C. pn pneumonia (p = 0.003). Purulent sputa were seen in 44% of C. pn pneumonia cases and 50% of M. pn pneumonia cases, and these rates were higher than that of 13% in C. ps pneumonia cases (p = 0.002, p = 0.004). Dyspnea and anorexia symptoms were the most frequent in C. pn pneumonia cases (24% and 29%, respectively, the highest of all three pneumonias). There were clinical differences between C. pn pneumonia and the other two atypical pneumonias. However, there was some difficulty in differentiating between C. pn pneumonia and typical bacterial pneumonia because mixed infections were common (24%) in C. pn pneumonia cases.     

肺炎衣原体急性呼吸道感染的临床研究

目的了解成人呼吸道感染患者急性肺炎衣原体感染的患病情况及临床特征。方法呼吸道感染住院患者１１０例，同时采集痰和咽拭子标本，应用聚合酶链反应（ＰＣＲ）检测肺炎衣原体ＤＮＡ，及采取静脉血检测肺炎衣原体ＩｇＧ和ＩｇＭ抗体。结果本组患者肺炎衣原体ＩｇＧ抗体的阳性率为７０％（７７／１１０），其中１７例（１６％）有肺炎衣原体近期感染的急性抗体，１２例（１１％）痰和（或）咽拭子肺炎衣原体ＰＣＲ检测结果阳性，联合应用两种方法的阳性率为２３％（２５／１１０）。肺炎衣原体急性感染以支气管哮喘急性发作、肺炎、慢性阻塞性肺疾病急性加重和急性支气管炎患者多见（分别为５７％、３５％、２６％和２５％），其临床表现无特征性。结论结果提示成人呼吸道感染患者肺炎衣原体急性感染的阳性率较高，提示肺炎衣原体是呼吸道感染的重要致病原，应引起临床的高度重视     

Chlamydia pneumoniae is an important cause of community-acquired pneumonia in school-aged children: serological results of a prospective, population-based study.

The aetiology of community-acquired pneumonia in childhood was studied in the total population of 8851 children in the area of 4 municipalities in eastern Finland. All cases of community-acquired pneumonia (n = 201) were registered during a surveillance period of 12 months between September 1, 1981 and August 31, 1982. The diagnosis of pneumonia was verified radiologically in all identified cases. The diagnosis of chlamydial infection was based on an antibody response measured by complement fixation (CF), by enzyme immunoassay (EIA; IgG or IgM) or by microimmunofluorescence (MIF; IgG or IgM), and the diagnosis of mycoplasmal infection on CF alone. In total, 29 cases of Chlamydia sp. infection were diagnosed; 20 were caused by Chlamydia pneumoniae. Thus, C. pneumoniae was an aetiological agent in 10%, of the 201 pneumonia cases: the proportion was 9% for children aged 5-9 y and 31% for those aged 10 y or more. In the study population, the total incidence of C. pneumoniae pneumonia was 2.3/1000/y. Mycoplasma pneumoniae serology (CF) was positive in 44 patients (22%); the total incidence of M. pneumoniae pneumonia was 5.0/1000/y. Serological evidence of both Chlamydiae and M. pneumoniae was detected in 9 (41%) patients. Our results indicate that C. pneumoniae is an important cause of community-acquired pneumonia in school-aged children. Diagnostic serological response to Chlamydia species or M. pneumoniae was found in 42% of pneumonia patients between 5 and 9 y of age and in 67% of patients aged 10 y or more. Thus, we suggest that macrolides should be considered as an empirical antimicrobial treatment for community-acquired pneumonia, especially in school-aged outpatients.