Etiology of acute pneumonias in an organized collective

In this work the immune structure of an organized group with respect to acute respiratory infections and the etiological structure of cases of acute pneumonia was studied. The sera taken from 602 persons were tested for the presence of antibodies to 14 infective agents of the viral, bacterial and mycoplasmal nature. The data indicate that all these agents circulate in the group under study with the prevalence of influenza A (H3N2), influenza B and group III parainfluenza viruses. Among etiological agents of acute pneumonia, the combination of Staphylococcus with Mycoplasma pneumoniae and adenovirus was noted. The Legionella etiology of some group cases of acute pneumonia among young persons was established on the basis of the increased titers of L. pneumophila antibodies in the indirect hemagglutination, indirect immunofluorescence and enzyme immunoassay. The source of this infection was highly dispersed water aerosol, containing the infective agent, in shower baths. This was bacteriologically confirmed by the isolation of three Legionella strains. The study showed that no transfer of Legionella infection in the group through contacts was possible.     

病毒性肺炎患者外周血干扰素刺激基因15 mRNA表达特征的研究

通过分析病毒性肺炎患者外周血干扰素刺激基因15(interferon stimulated gene 15,ISG15)mRNA在感染状态下的特征性表达,探究ISG15与病毒性肺炎发病机制及疾病活动性之间的可能联系,为探索特异性呼吸道病毒感染的宿主生物标志物提供依据.本研究共收集157例社区获得性肺炎(communit...     

Etiology of pneumonia in children in the absence of pneumococcal and antihaemophilus vaccines

Childhood pneumonia represents an important pathology, a cause of morbidity and mortality worldwide. Our study aims to determine etiology of pneumonia in hospitalized children using several laboratory methods. We performed a prospective study that enrolled 560 children age 1 up to 18 years old all diagnosed with pneumonia by clinical and radiological features. We applied various laboratory methods (serologic, bacteriologic: bronchial aspirate, sputum, pleural effusion and blood culture) in order to identify a pathogen agent that caused pneumonia. Statistics used Statistical Package for Social Science. An etiology was established in 68.92% of all cases included in the study, as follows: in 33.93% viral etiology, in 25.13% we identified Streptococcus pneumoniae, in 20.2% Mycoplasma pneumoniae, Klebsiella pneumoniae in 8.29%, Staphylococcus aureus in 7.51%, Haemophilus influenzae in 4.92%. Mixed bacterial and viral infection was identified in 4.40% of all cases. A potential causative agent of childhood pneumonia was determined in most cases, S. pneumoniae being the main agent involved in community acquired childhood pneumonia in our country.     

Significance of Legionella pneumophila in human respiratory pathology

The etiological structure of acute pneumonia and acute respiratory diseases was studied with a view to establishing the proportion of L. pneumophila among other causative agents of such diseases. A total of 299 patients were examined over time. The etiological diagnosis based on the data of serological examination was made in 70.6% of the patients with acute pneumonia and in 65% of the patients with acute respiratory viral infections and influenza. In the etiology of pneumonia, the leading role was found to belong to influenza A (H3N2) and B viruses, as well as to adenovirus, while in the etiology of acute respiratory viral infections and influenza, to influenza B virus, adenovirus and Mycoplasma pneumoniae. The importance of L. pneumophila in the etiology of acute pneumonia and acute respiratory diseases was shown. The proportion of L. pneumophila proved to be, on the average, 9.9% in acute pneumonia and 9.8% in acute respiratory diseases. L. pneumophila occurred most frequently in mixed infections in combination with adenovirus and influenza B virus. Diseases of Legionella etiology were found to have a seasonal character, occurring mostly in winter and spring.     

Etiology of acute pneumonia occurring against a background of influenza and other acute respiratory viral infections

The etiology of acute pneumonia (AP) was studied in 229 patients who had the disease simultaneously with influenza (106 patients), other viral and mycoplasmal infections (48 patients), and without concomitant acute viral infections (75 patients). The use of the quantitative microbiological method and the indirect immunofluorescence test with autostrains or Streptococcus pneumoniae strains of serotypes 2, 3, and 6, prevailing in Leningrad in patients with acute inflammatory diseases of the lungs, made it possible to find out the pneumococcal etiology of AP in 95% of patients irrespective of the presence of acute respiratory viral infections. The etiological role of opportunistic bacteria was revealed in 13 AP patients (5.7%); in 2 of them the causative agent of AP was Staphylococcus aureus and in 11, various species of Gram-negative enterobacteria. The latter were the cause of complications in 8 cases of pneumococcal pneumonia.     

Pneumococcal and chlamydial infections in a closed community

An epidemic outbreak of acute respiratory infection (295 patients) in an organized group of young people was observed in December-May 1997-1998. Pneumococcal etiology was established by means of indirect immunofluorescence reaction in cases of outpatient pneumonia (81.9%), acute bronchitis (80%) and acute respiratory diseases (92.5%). Respiratory chlamydiosis caused by Chlamydia pneumoniae was detected in enzyme immunoassay with the use of immunoComb Chlamydia Bivalent IgG in patients with pneumonia (66.7%), acute bronchitis (60%) and acute respiratory diseases (50%). Synergic relationship between pneumococcal and chlamydial infections was noted.     

Usefulness of Cellular Analysis of Bronchoalveolar Lavage Fluid for Predicting the Etiology of Pneumonia in Critically Ill Patients

Background

The usefulness of bronchoalveolar lavage (BAL) fluid cellular analysis in pneumonia has not been adequately evaluated. This study investigated the ability of cellular analysis of BAL fluid to differentially diagnose bacterial pneumonia from viral pneumonia in adult patients who are admitted to intensive care unit.

Methods

BAL fluid cellular analysis was evaluated in 47 adult patients who underwent bronchoscopic BAL following less than 24 hours of antimicrobial agent exposure. The abilities of BAL fluid total white blood cell (WBC) counts and differential cell counts to differentiate between bacterial and viral pneumonia were evaluated using receiver operating characteristic (ROC) curve analysis.

Results

Bacterial pneumonia (n = 24) and viral pneumonia (n = 23) were frequently associated with neutrophilic pleocytosis in BAL fluid. BAL fluid median total WBC count (2,815/µL vs. 300/µL, P<0.001) and percentage of neutrophils (80.5% vs. 54.0%, P = 0.02) were significantly higher in the bacterial pneumonia group than in the viral pneumonia group. In ROC curve analysis, BAL fluid total WBC count showed the best discrimination, with an area under the curve of 0.855 (95% CI, 0.750–0.960). BAL fluid total WBC count ≥510/µL had a sensitivity of 83.3%, specificity of 78.3%, positive likelihood ratio (PLR) of 3.83, and negative likelihood ratio (NLR) of 0.21. When analyzed in combination with serum procalcitonin or C-reactive protein, sensitivity was 95.8%, specificity was 95.7%, PLR was 8.63, and NLR was 0.07. BAL fluid total WBC count ≥510/µL was an independent predictor of bacterial pneumonia with an adjusted odds ratio of 13.5 in multiple logistic regression analysis.

Conclusions

Cellular analysis of BAL fluid can aid early differential diagnosis of bacterial pneumonia from viral pneumonia in critically ill patients.     

Procalcitonin and C-reactive protein for invasive bacterial pneumonia diagnosis among children in Mozambique, a malaria-endemic area

Background

Pneumonia is the major cause of mortality and morbidity in children worldwide. Procalcitonin (PCT) and C-reactive protein (CRP) are used in developed countries to differentiate between viral and bacterial causes of pneumonia. Validity of these markers needs to be further explored in Africa.

Methodology and Principal Findings

We assessed the utility of PCT and CRP to differentiate viral from invasive bacterial pneumonia in children <5 years hospitalized with clinical severe pneumonia (CSP) in rural Mozambique, a malaria-endemic area with high HIV prevalence. Prognostic capacity of these markers was also evaluated. Out of 835 children with CSP, 87 fulfilled definition of viral pneumonia and 89 of invasive bacterial pneumonia. In absence of malaria parasites, levels of PCT and CRP were lower in the viral group when compared to the invasive bacterial one (PCT: median = 0.21 versus 8.31 ng/ml, p<0.001; CRP: 18.3 vs. 185.35 mg/l, p<0.001). However, in presence of malaria parasites distribution between clinical groups overlapped (PCT: median = 23.1 vs. 21.75 ng/ml, p = 0.825; CRP: median = 96.8 vs. 217.4 mg/l, p = 0.052). None of the two markers could predict mortality.

Conclusions

Presence of malaria parasites should be taken into consideration, either for clinical or epidemiological purposes, if using PCT or CRP to differentiate viral from invasive bacterial pneumonia in malaria-endemic areas.     

病毒性心肌炎与支原体肺炎患儿心肌损伤标志物水平的检验意义

目的:探讨病毒性心肌炎与支原体肺炎患者心肌损伤标志物水平检测意义。方法:回顾性分析医院收治的病毒性心肌炎患儿53例和肺炎支原体肺炎患儿49例分别作为病毒性心肌炎组和支原体肺炎组,选取同期体检正常儿童50例作为对照组,分别检测心肌酶指标和心肌蛋白指标。结果:病毒性心肌炎组心肌肌钙蛋白I(c Tnl)、肌红蛋白(MYO)显著高于支原体肺炎组、对照组,差异显著(P0.05);支原体肺炎组和对照组组间差异显著,具有统计学意义(P0.05)。病毒性心肌炎组肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、门冬氨酸氨基转移酶(AST)、乳酸脱氢酶(LDH)均显著高于支原体肺炎组、对照组,差异显著(P0.05);支原体肺炎组、对照组组间对比差异显著,具有统计学意义(P0.05)。2组入院10 d c Tnl、MYO均低于入院第1 d,具有统计学意义(P0.05);病毒性心肌炎组入院第10 d c Tnl、MYO显著高于支原体肺炎组,具有统计学意义(P0.05)。2组入院10 d CK、CK-MB、AST、LDH均低于入院第1 d,具有统计学意义(P0.05);病毒性心肌炎组入院第10 d CK、CK-MB、AST显著高于支原体肺炎组,差异具有统计学意义(P0.05)。根据ROC曲线分析临床性能,c Tnl、MYO、CK、CK-MB、AST、LDH的临界值分别为0.38μg/L、56.2μg/L、236.58 U/L、32.8 U/L、71.6 U/L、232.8 U/L,灵敏度分别为82.7%、85.4%、84.8%、89.6%、90.2、79.8%。结论:心肌损伤标志物可作为诊断病毒性心肌炎和支原体肺炎的重要指标,应用ROC回归曲线确定各指标的临界值,还可对两种疾病进行鉴别诊断。     

Serological and epidemiological characteristics of acute pneumonias caused by Mycoplasma pneumoniae in Belgorod

The etiology of the outbreaks of acute pneumonia in Belgorod was established and their epidemiological features were studied. The mycoplasmal etiology of all cases of acute pneumonia in children and adults, appearing alongside acute respiratory infections resulting from the preceding outbreaks caused by influenza viruses A/Prague/, B/Leningrad/369/75, and all types of parainfluenza viruses, was shown. The droplet mechanism of the transfer of infection was established, which was confirmed by the severity of the outbreak and a high rate of infection of the medical staff at hospitals for children and adults, where patients with mycoplasma-induced pneumonia were treated.     

The diagnostic accuracy of high-mobility group box 1 protein and twelve other markers in discriminating bacterial, viral and co-infected bronchial pneumonia in Han children

Pneumonia in children is common and can lead to grave consequences if not addressed in a proper and timely manner. In the management of pneumonia, early identification of the causative infective agent is of obvious importance for treatment, as it allows selection of the appropriate antibiotics. However, such identification requires laboratory test results, which may not be immediately available. The aim of this study was to evaluate the accuracy and usefulness of 13 markers in differentiating between viral and bacterial pneumonia in Han children (34 healthy controls and 78 patients). It was found that WBC counts were more accurate in diagnosis of the type of agent responsible for infection than was the degree of expression of HMGB1. Among the 13 markers investigated, HMGB1 was the best at discriminating between co-infected (bacterium and virus) and single-infected (bacterium or virus) children with bronchial pneumonia. HMGB1 expression of less than 1.0256, excluded most co-infections (the negative predictive value was greater than 89.7%). Diagnosed sole viral pneumonia clinically overlapped with bacterial pneumonia, but bacterial pneumonia was more often associated with higher white blood cell (WBC) counts (WBC ≥ 13,000 cells/mm(3)). When the two marker readouts--HMGB1 < 1.0256 and WBC ≥ 13,000 cells/mm(3)--were combined, the positive predictive value for bacterial pneumonia alone was 92.3%. These findings can help clinicians discriminate between bronchial pneumonia caused by virus, bacterium or both with a high specificity.     

阿齐霉素联合头孢噻肟钠治疗老年社区获得性肺炎

目的探讨阿齐霉素联合头孢噻肟对老年社区获得性肺炎(CAP)的临床效果和安全性。方法84例老年CAP随机分为2组。治疗组42例,给阿齐霉素0.5 g,po,qd,连用3 d,同时给头孢噻肟钠2.0 g,静滴,bid。对照组42例,给头孢噻肟钠2.0 g静滴,bid。2组总疗程14 d。结果治疗组与对照组的总有效率分别为90.5%和73.8%,差异有显著性(P<0.05);治疗组与对照组的细菌总清除率分别为80.0%和78.9%,差异无显著性(P>0.05)。结论阿齐霉素联用头孢噻肟钠治疗老年社区获得性肺炎安全、有效。     

Pneumonia in Indian and Eskimo Infants and Children: Part I. A Clinical Study

Ninety-seven Indian and Eskimo infants and children who suffered 112 episodes of pneumonia were the subjects of a prospective study carried out at the Charles Camsell Hospital, Edmonton, Alberta, from August 1963 until August 1964. Investigation included viral studies and an evaluation 10 days after admission. The patients were divided into four diagnostic categories and a comparison was made between cases of bacterial and viral origin. The frequency of right-sided disease, particularly of the upper lobe and/or dependent segment involvement, is described. An evaluation of physical signs is attempted. The problem of recurrent pneumonia and the differential diagnosis of tuberculosis in Indian and Eskimo children with pneumonia is discussed.     

闽南地区5 869例儿童社区获得性肺炎患者 病原学特点分析

目的通过对闽南地区社区获得性肺炎(CAP)患儿病原特点进行分析,为CAP早期预警、预防和早期经验治疗提供指导和依据。方法收集我院2015年1月至2017年5月5 869例CAP患儿静脉血、呼吸道分泌物及痰标本分别进行肺炎支原体(MP)、呼吸道病毒检测以及细菌培养和鉴定。结果 5 869例CAP患儿中明确病原体感染4 931例,其中单纯细菌感染3 054例,单纯病毒感染966例,单纯MP感染620例,混合感染291例,未检出病原体938例。细菌性病原主要以肺炎链球菌、流感嗜血杆菌和卡他莫拉菌为主,在各季节检出率不同且男性多于女性,主要在低龄儿童中检出。病毒感染者主要分布于低龄儿童,夏季检出率最高,病原以呼吸道合胞病毒(RSV)为主,占68.22%。该类患者在性别上比较差异无统计学意义。MP感染者中女性多于男性,主要分布于大龄儿童,冬季检出率最高。结论本地区CAP患儿病原检出率由高到低分别为细菌、病毒和MP。细菌和MP检出率在患儿中具有性别差异,各种病原在不同年龄段儿童及季节中检出率不同。     

Characteristic of the etiologic structure of acute enteric infections in adults based on the data from infectious diseases hospital

Study of the etiologic spectrum of sporadic cases of causative agents of acute enteric infections (AEI) in 753 patients aged 15-85 years old using polymerase chain reaction (PCR) was performed in the infectious diseases hospital during 12 months. It was shown that detection of the causative agents of AEI by PCR was 2.2 times more effective than routine microbiologic diagnostics supplemented with test of feces on rotavirus by ELISA method and allowed to detect etiologic agent in 54.3% of the patients. Viral etiology of AEI was determined in 22.6% of the patients. The most significant causative agents of AEI comparable on the rate of detection with salmonella and shigella were genotype 2 noroviruses and group A rotaviruses which were isolated in 10.4 and 8.9% of the patients respectively. Seasonal change of dominating viral pathogens causing diarrheal diseases was noted: predominance of group A rotaviruses during winter-spring period, noroviruses--during spring-summer months, and astroviruses--during fall and in the beginning of winter.     

Particulate matter exposure predicts residence in high-risk areas for community acquired pneumonia among hospitalized children

Particulate matter exposure is a risk factor for lower respiratory tract infection in children. Here, we investigated the geospatial patterns of community-acquired pneumonia and the impact of PM_2.5 (particulate matter with an aerodynamic diameter ≤2.5 µm) on geospatial variability of pneumonia in children. We performed a retrospective analysis of prospectively collected population-based surveillance study data of community-acquired pneumonia hospitalizations among children <18 years residing in the Memphis metropolitan area, who were enrolled in the Centers for Disease Control and Prevention sponsored Etiology of Pneumonia in the Community (EPIC) study from January 2010 to June 2012. The outcome measure, residence in high- and low-risk areas for community-acquired pneumonia, was determined by calculating pneumonia incidence rates and performing cluster analysis to identify areas with higher/lower than expected rates of community-acquired pneumonia for the population at risk. High PM_2.5 was defined as exposure to PM_2.5 concentrations greater than the mean value (>10.75 μg/m³), and low PM_2.5 is defined as exposure to PM_2.5 concentrations less than or equal to the mean value (≤10.75 μg/m³). We also assessed the effects of age, sex, race/ethnicity, history of wheezing, insurance type, tobacco smoke exposure, bacterial etiology, and viral etiology of infection. Of 810 (96.1%) subjects with radiographic community-acquired pneumonia, who resided in the Memphis metropolitan area and had addresses which were successfully geocoded (Supplementary Figure F2), 220 (27.2%) patients were identified to be from high- (n = 126) or low-risk (n = 94) community-acquired pneumonia areas. Community-acquired pneumonia in Memphis metropolitan area had a non-homogenous geospatial pattern. PM_2.5 was associated with residence in high-risk areas for community-acquired pneumonia. In addition, children with private insurance and bacterial, as opposed to viral, etiology of infection had a decreased risk of residence in a high-risk area for community-acquired pneumonia. The results from this paper suggest that environmental exposures as well as social risk factors are associated with childhood pneumonia.     

Comparative information value of humoral immunity characteristics in some bacterial and viral infections

Serological examination of 144 patients with different bacterial and viral infections was carried out. Antibodies to Brucella were detected in blood serum in 42 patients (85.7%) with the average titer of 1:996 and in saliva in 41 patients (83.7%) with the average titer of 1:567 by passive hemagglutination test with brucella erythrocyte diagnosticum. Out of 26 dysentery patients, antibodies in blood serum were detected in the diagnostic titer in 17 patients (65.4%) with the average titer of 1:282 and in saliva in 21 patients (80.8%) in the titer of 1:100 and higher. Anti-HAV and anti-HBc IgM were detected in specimens of saliva from patients with serologically confirmed viral hepatitis A and B in 100% of cases. The presence of HBsAg in saliva from hepatitis B patients was established in 95.4% of cases. In blood serum and in specimens of saliva anti-HCV IgM were detected in 100% and 85.7% of cases respectively. Out of 25 women with aggravated obstetric history, IgG antibodies to CMV were detected in blood serum in 23 women (88.5%) and in saliva in 22 women (84.6%). The results of these investigations revealed that the detection rate of antibodies in blood serum and saliva in cases of infections, both bacterial (brucellosis, shigellosis) and viral (hepatitis A, B, C and CMV infection), was not essentially different. The simplicity of obtaining material for analysis make it possible to recommend the use of saliva for diagnosing bacterial and viral infections, especially in mass epidemiological surveys.     

Clinical Characteristics and Outcomes in Hospitalized Patients with Respiratory Viral Co-Infection during the 2009 H1N1 Influenza Pandemic

Background

The clinical consequences of co-infection with two or more respiratory viruses are poorly understood. We sought to determine if co-infection with pandemic 2009–2010 influenza A H1N1 (pH1N1) and another respiratory virus was associated with worse clinical outcomes.

Methods

A retrospective cohort study was performed of all hospitalized patients with a positive respiratory viral panel (RVP) for two or more viruses within 72 hours of admission at our institution from October 2009 to December 2009. We compared patients infected with one respiratory virus to those with respiratory viral co-infection.

Results

We identified 617 inpatients with a positive RVP sample with a single virus and 49 inpatients with a positive RVP sample for two viruses (i.e. co-infection). Co-infected patients were significantly younger, more often had fever/chills, tachypnea, and they more often demonstrated interstitial opacities suggestive of viral pneumonia on the presenting chest radiograph (OR 7.5, 95% CI 3.4–16.5). The likelihood of death, length of stay, and requirement for intensive care unit level of care were similar in both groups, but patients with any respiratory virus co-infection were more likely to experience complications, particularly treatment for a secondary bacterial pneumonia (OR 6.8, 95% CI 3.3–14.2). Patients co-infected with pH1N1 and another respiratory virus were more likely to present with chest radiograph changes suggestive of a viral pneumonia, compared to mono-infection with pH1N1 (OR 16.9, 95% CI 4.5–62.7). By logistic regression using mono-infection with non-PH1N1 viruses as the reference group, co-infection with pH1N1 was the strongest independent predictor of treatment for a secondary bacterial pneumonia (OR 17.8, 95% CI 6.7–47.1).

Conclusion

Patients with viral co-infection, particularly with pH1N1, were more likely to have chest radiograph features compatible with a viral pneumonia and complications during their hospital course, particularly treatment for secondary bacterial pneumonia. Despite this, co-infection was not associated with ICU admission.