No abstract

The American Thoracic Society (ATS) published guidelines for the treatment and management of community-acquired pneumonia in 2001, but the impact of adherence on outcomes such as mortality and length of stay is not well defined.A study of 780 patients with community-acquired pneumonia consecutively admitted to hospital over 1 yr was carried out. Nursing home patients were excluded.Overall adherence to antibiotics recommended in the ATS guidelines was 84%. The lowest adherence was found in patients admitted to an intensive care unit (52%), especially those at risk of infection withPseudomonas aeruginosa(ATS group IVb). However, very few patients from this group were indeed infected withP. aeruginosa. This could be explained by the exclusion of the nursing home patients. There was a difference in mortality between patients that received adherent and nonadherent regimens (3versus10.6%). There was a difference in length of stay between patients receiving adherent and nonadherent regimens (7.6versus10.4 days). This result was confirmed on multivariate analysis.Adherence to the 2001 American Thoracic Society guidelines was high except in community-acquired pneumonia patients admitted to an intensive care unit. Length of stay was shorter in patients who received adherent rather than nonadherent antibiotic regimens.

The main reasons for administering systemic steroids were the presence of chronic respiratory comorbidity or severe clinical presentation, but therapy did not influence mortality or clinical stability; by contrast, steroid administration was associated with prolonged length of stay. Nevertheless the steroid group did not show an increased mortality as it was expected according to the initial Pneumonia Severity Index score. Influence of steroids on outcomes of CAP need to be further investigated through randomized clinical trial.

Background The role of viruses in community-acquired pneumonia may have been previously underestimated. We aimed to study the incidence and clinical characteristics of community-acquired pneumonia (CAP) due to respiratory viruses in adults adding PCR to routine conventional laboratory tests. Methods Consecutive adult patients diagnosed of CAP from January 2003 to March 2004 were included. Conventional tests including cultures of blood, sputum, urine antigen detection of Streptococcus pneumoniae and Legionella pneumophila, and paired serologies were routinely performed. Nasopharyngeal swabs were processed for study of respiratory viruses through antigen detection by indirect immunofluorescence assay, isolation of viruses in cell culture and detection of nucleic acids by two independent multiplex RT-PCR assays. According to the aetiology, patients were categorized in 4 groups: group 1, only virus detected; group 2, only bacteria detected; group 3, viral and bacterial; and group 4, unkown aetiology. Results Of 340 patients diagnosed with CAP, 198 had nasopharyngeal swabs available and were included in this study. Aetiology was established in 112 (57%) patients: group 1, n=26 (13%); group 2, n=66 (33%); group 3, n=20 (10%). The most common aetiological agent was S. neumoniae (58 patients, 29%), followed by respiratory viruses (46 patients, 23%). Forty-eight respiratory viruses were identified: influenza virus A ( n=16), respiratory syncytial virus A ( n=5), adenovirus ( n=8), parainfluenza viruses ( n=5), enteroviruses ( n=1), rhinoviruses ( n=8) and coronavirus ( n=5). There were two patients coinfected by two respiratory viruses. Serology detected 6 viruses, immunofluorescence 8, viral culture 12, and PCR 45. For the viruses that could be diagnosed with conventional methods, the sensitivity and specificity of RT-PCR was 85% and 92%, respectively. The only clinical characteristic that significantly distinguished viral from bacterial aetiology was a lower number of leukocytes ( P=0.004). Conclusion PCR revealed that viruses represent a common aetiology of CAP. There is an urgent need to reconsider routine laboratory tests for an adequate diagnosis of respiratory viruses, as clinical characteristics are unable to reliably distinguish viral from bacterial aetiology.