Single and Multiple Viral Infections in Lower Respiratory Tract Infection

Abstract

Background: Lower respiratory tract infection (LRTI) often leads to hospitalization, and it was indicated that causative viral infections are underestimated. Objectives: It was our aim to compare the frequency of 8 relevant viruses in 109 hospitalized LRTI patients and 144 healthy controls. Methods: Virus infection was determined by seroconversion and ELISA for anti-virus antibodies in repeated serum samples. Bacterial infection was diagnosed in respiratory specimens, blood cultures and urine. Results: The LRTI patient cohort consisted of 49 patients with community-acquired pneumonia, 30 patients with acute bronchitis and 30 chronic obstructive pulmonary disease patients with acute exacerbation. Viral infection was detected in 89 (82%) LRTI patients compared with 32 (22%) in healthy controls (relative risk 3.42, 95% confidence interval 2.48–4.72; p < 0.0001). The most frequent viral pathogens were: influenza B (23%), adenovirus (16%) and parainfluenza virus 3 (12%). Importantly, infections with more than 1 virus were detected in 63% (n = 57) of LRTI patients with viral infection, which represents 52% of all LRTI patients. No multiple virus infection was detected in the healthy controls. Patients with community-acquired pneumonia were more often infected with adenovirus and respiratory syncytial virus as compared with the other LRTI patients (p = 0.046 and 0.0009, respectively). Conclusions: There is a high incidence of single and multiple viral infections in LRTI patients requiring hospitalization. The data indicate the need for regular virus diagnosis and the development of point of care tools that enables a fast diagnosis of the most common viruses and bacteria. The data also imply the need to consider antiviral therapy in positive LRTI cases.

Altered Phenotype of Blood Dendritic Cells in Patients with Acute Pneumonia

“…Firstly, the majority of patients (79%) displayed PCT concentrations >0.25 ng/ml. This cut-off has been proposed to identify patients with a bacterial community-acquired pneumonia eligible for antibiotic treatment [21,22]. Secondly, all patients included in the study responded well to antibiotic treatment.…”

Antibiotic prescribing for acute bronchitis

“…The microbiological etiology of acute bronchitis is related to the season of the year (see Table 1). However, the etiology may be caused by more than one microorganism and multiple pathogens have been detected in up to 30% of patients with acute bronchitis [12]. Physical findings are generally non-specific, but lung examination in some patients can reveal wheezing.…”

Levels of Soluble Triggering Receptor Expressed on Myeloid Cells 1 in Infectious Exacerbations of Chronic Obstructive Pulmonary Disease

“…During these exacerbations, airway inflammation is increased and, in addition, in some patients, an increased systemic inflammatory response is detectable [19,20]. Exacerbations may have many different triggers, the most common being microbial infection, bacterial [21] or viral [22,23]. The use of antibiotics during acute exacerbation is often debated due to the fact that bacterial infections cannot always be proven.…”