Viral and bacterial aetiology of community‐acquired pneumonia in adults

Abstract

Please cite this paper as: Huijskens et al. (2012) Viral and bacterial aetiology of community‐acquired pneumonia in adults. Influenza and Other Respiratory Viruses 7(4), 567–573. Background Modern molecular techniques reveal new information on the role of respiratory viruses in community‐acquired pneumonia. In this study, we tried to determine the prevalence of respiratory viruses and bacteria in patients with community‐acquired pneumonia who were admitted to the hospital. Methods Between April 2008 and April 2009, 408 adult patients (aged between 20 and 94 years) with community‐acquired pneumonia were tested for the presence of respiratory pathogens using bacterial cultures, real‐time PCR for viruses and bacteria, urinary antigen testing for Legionella and Pneumococci and serology for the presence of viral and bacterial pathogens. Results Pathogens were identified in 263 (64·5%) of the 408 patients. The most common single organisms in these 263 patients were Streptococcus pneumoniae (22·8%), Coxiella burnetii (6·8%) and influenza A virus (3·8%). Of the 263 patients detected with pathogens, 117 (44·5%) patients were positive for one or more viral pathogens. Of these 117 patients, 52 (44·4%) had no bacterial pathogen. Multiple virus infections (≥2) were found in 16 patients. Conclusion In conclusion, respiratory viruses are frequently found in patients with CAP and may therefore play an important role in the aetiology of this disease.

Incidence of Respiratory Viral Infections Detected by PCR and Real-Time PCR in Adult Patients with Community-Acquired Pneumonia: A Meta-Analysis

“…Due to the high level of heterogeneity, the subgroup analysis was performed according to the patient types, economic level of the countries and regions where the studies were performed, as mentioned above. The combined incidence of coinfections was 12.9% (95% CI = 9.7-16.1, I 2 = 91.3%) in inpatients with CAP [7,14,15,16,17,18,19,21,22,24,26,27,28] and 13.7% (95% CI = 7.1-20.3, I 2 = 90.6%) in mixed patients with CAP [29,30,31,32]. Since only 1 study provided the incidence of coinfections in outpatients with CAP [12], a combined estimate was not performed.…”

“…Considering the high level of heterogeneity, we further conducted a subgroup analysis for the separate calculation of combined incidences according to the types of patients (inpatients, outpatients and mixed patients), time span of patient enrollment (1 year vs. >1 year), economic level of the countries (developed vs. developing countries), PCR methods (routine PCR vs. real-time PCR) or according to the region where each report was conducted (Europe, Southeast Asia, Australia, America and the Middle East), as shown in table 2. The combined incidence of respiratory viruses was 10.2% (95% CI = 7.3-13.1, I 2 = 0%) in outpatients [11,12], 22.7% (95% = 19.0-26.4, I 2 = 90.8%) in inpatients [7,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,31,32] and 27.7% (95% = 16.4-39.0, I 2 = 94.7%) in mixed patients [29,30]. In the subgroup analysis according to regions, the combined incidence was highest in the Middle East (32%, 95% CI = 27-38, I 2 = 0%) [21,23] and lowest in Southeast Asia (16.6%, 95% CI = 10.5-22.8, I 2 = 85.1%) [11,12,15,19,32].…”

“…Of the 23 reports, 18 studies [7,12,14,15,16,17,18,19,20,21,22,24,26,27,28,29,30,31,32] provided data for the calculation of the coinfection incidences of respiratory viruses with other pathogens (n = 5,058). As shown in figure 3, the incidence estimates of coinfections ranged from 3 to 28%; heterogeneity was considerable (χ 2 = 200.9, p < 0.0001, I 2 = 91.5%).…”

“…Ten of the 23 reports achieved a score ≥7, and the other 13 reports scored between 4 and 6. Of the 23 reports, 2 were conducted in adult outpatients with CAP [11,12], 17 in adult inpatients with CAP [7,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28] and 4 in both outpatients and inpatients with CAP [29,30,31,32]. Nine reports were carried out in Europe (4 in Spain, 3 in the Netherlands, 1 in the UK and 1 in Sweden) [7,14,17,18,20,24,28,29,30], 5 in Southeast Asia (2 in China, 1 in Japan, 1 in Korea and 1 in Vietnam) [11,12,15,19,32], 3 in Australia [22,26,27], 4 in America (2 in the USA, 1 in Canada and 1 in Chile) [13,16,25,31] and 2 in Israel [21,23].…”

“…Nine reports were carried out in Europe (4 in Spain, 3 in the Netherlands, 1 in the UK and 1 in Sweden) [7,14,17,18,20,24,28,29,30], 5 in Southeast Asia (2 in China, 1 in Japan, 1 in Korea and 1 in Vietnam) [11,12,15,19,32], 3 in Australia [22,26,27], 4 in America (2 in the USA, 1 in Canada and 1 in Chile) [13,16,25,31] and 2 in Israel [21,23]. Moreover, respiratory viral detection in 12 studies was solely based on PRC/real-time PCR [7,11,12,13,14,15,16,17,18,19,23,27,29], and viral detection in the other studies was based on a combination of PCR/real-time PCR and conventional methods [20,21,22,24,25,26,28,30,31,32]. …”