The value of signs and symptoms in differentiating between bacterial, viral and mixed aetiology in patients with community-acquired pneumonia

Abstract

Current diagnostics for community-acquired pneumonia (CAP) include testing for a wide range of pathogens, which is costly and not always informative. We compared clinical and laboratory parameters of patients with CAP caused by different groups of pathogens to evaluate the potential for targeted diagnostics and directed treatment. In a prospective study, conducted between April 2008 and April 2009, adult patients with CAP were tested for the presence of a broad range of possible respiratory pathogens using bacterial cultures, PCR, urinary antigen testing and serology. Of 408 patients with CAP, pathogens were detected in 263 patients (64.5 %). Streptococcus pneumoniae and influenza A virus were the most frequently identified bacterial and viral pathogens, respectively. Age had a significant effect on the prediction of aetiology (P50.054), with an increase in the relative contribution of viruses with advancing age. Multivariate analyses further showed that the presence of cough increased the likelihood of detecting a viral pathogen [odds ratio (OR) 5.536, 95 % confidence interval (CI) 2.130-14.390], the presence of immunodeficiency decreased the likelihood of detecting a bacterial pathogen (OR 0.595,) and an increase in pneumonia severity index score increased the likelihood of detecting a pathogen in general. Although several variables were independently associated with the detection of a pathogen group, substantial overlap meant there were no reliable clinical predictors to distinguish aetiologies. Therefore, testing for common respiratory pathogens is still necessary to optimize treatment.

Viral infection in community-acquired pneumonia: a systematic review and meta-analysis

“…The most commonly identified viruses were influenza in 18 studies [3, 6, 7, 10, 11, 17-19, 21, 23, 26, 27, 29, 31, 32, 34-36], rhinovirus in eight studies [1,5,8,12,22,24,25,28], respiratory syncytial virus in three studies [2,9,33] and coronavirus in two studies [20,30]. Meta-analyses revealed that the proportion of infection by influenza (31 studies) was 8% (95% CI 6.3-9.6%; I 2 =91.9%), by rhinovirus (25 studies) was 5.7% (95% CI 4.3-7.1%; I 2 =90.3%), by respiratory syncytial virus (29 studies) was 2.2% (95% CI 1.6-2.8%; I 2 =80%) and by coronavirus (18 studies) was 3.3% (95% CI 2.3-4.2%; I 2 =80.2%).…”

“…For the outcome short-term mortality, we pooled data from 13 studies [2,3,6,7,24,26,28,29,[31][32][33][34][35]. The odds of death were higher in patients with viral infection, but there was no statistical significance (OR 1.3, 95% CI 0.8-2.16; p=0.283; I 2 =44.1%) (figure 3).…”

“…In patients with dual bacterial and viral infection (10 studies), the odds of death were significantly higher compared with patients without dual infection (OR 2. [3] SAITO [32] HOLM [22] JENNINGS [8] HOHENTHAL [21] CHARLES [17] JOHNSTONE [27] DIEDEREN [20] MERMOND [7] SHIBLI [34] JOHANSSON [26] LIEBERMAN [30] HARA [6] CILLÓNIZ [18] CHOI [2] SANGIL [33] YIN [36] VAN GAGELDONK-LAFEBER [5] LUCHSINGER [9] TAKAHASHI [10] WIEMKEN [11] MUSHER [12] VIASUS [35] HUIJSKENS [24] KIM [29] KARHU [28] HOLTER [23] QU [31] DAS [19] JAIN [25] …”

Neumonía adquirida en la comunidad

“…La diferenciación entre pacientes con cuadro clínico típico o atípico (según la presencia o ausencia, respectivamente, de 3 o más de las siguientes manifestaciones: inicio brusco, escalofríos, dolor pleurítico, expectoración purulenta, semiología franca y leucocitosis) no tiene utilidad predictiva absoluta, pero se correlaciona con una mayor o menor probabilidad de agentes bacterianos convencionales o atípicos, y sigue siendo de utilidad práctica, particularmente para pacientes con NAC poco grave 22,23 .…”

Community-acquired pneumonia

“…The same is true when faced with a patient with fever with no respiratory manifestations. 22,23 Apart from these general clinical variables, various pathogens have been correlated with specific clinical and epidemiological findings (Table 1). The presence of pleuritic pain or very obvious symptomatology can be of considerable use.…”