[Show abstract][Hide abstract] ABSTRACT: Viral pathogens have not generally been regarded as important causes of severe hospital-acquired pneumonia (HAP), except in patients with hematologic malignancy or transplant recipients. We investigated the role and distribution of viruses in adult with severe HAP who required intensive care.
From March 2010 to February 2012, adult patients with severe HAP required admission to the intensive care unit (ICU), 28-bed medical ICU in a tertiary care hospital, were prospectively enrolled. Respiratory viruses were detected using multiplex reverse-transcription polymerase chain reaction and/or shell vial culture.
A total of 262 patients were enrolled and 107 patients (40.8%) underwent bronchoscopic BAL for etiologic diagnosis. One hundred and fifty-six patients (59.5%) had bacterial infections and 59 patients (22.5%) had viral infections. Viruses were detected in BAL fluid specimens of 37 patients (62.7%, 37/59). The most commonly identified viruses were respiratory syncytial virus and parainfluenza virus (both 27.1%, 16/59), followed by rhinovirus (25.4%, 15/59), and influenza virus (16.9%, 10/59). Twenty-one patients (8.0%, 21/262) had bacterial-viral coinfections and Staphylococcus aureus was the most commonly coexisting bacteria (n = 10). Viral infection in non-immunocompromised patients was not uncommon (11.1%, 16/143), although it was not as frequent as that in immunocompromised patients (36.4%, 43/119). Non-immunocompromised patients were significantly older than immunocompromised patients and had significantly higher rates of underlying chronic obstructive pulmonary disease, tuberculous destroyed lung and chronic kidney disease. The 28 day mortalities of patients with bacterial infections, viral infections and bacterial-viral coinfections were not significantly different (29.5%, 35.6% and 19.0%, respectively; p = 0.321).
Viral pathogens are not uncommon in adult patients with severe HAP who required ICU admission. Since viral pathogens may cause severe HAP and could be a potential source of viral transmission, further investigation is required to delineate the role of viral pathogens in severe HAP.
[Show abstract][Hide abstract] ABSTRACT: Background: Healthcare-associated pneumonia (HCAP) is a category of community-onset pneumonia that has risk factors for antibiotic-resistant pathogen, and requires broader spectrum treatment. HCAP was incorporated into ATS/IDSA 2005 hospital-acquired pneumonia (HAP) guidelines, which recommends same empirical treatment strategies for HCAP and HAP. However there is little data that compares the bacterial etiologies of HCAP and HAP.
Methods: A prospective cohort study was conducted at a 28-bed medical ICU at a tertiary care hospital between March 2010 and February 2011. Bacterial etiologies of consecutive severe HCAP and HAP. patients requiring ICU admission were prospectively monitored and compared.
Results: A total of 307 patients (154 with HCAP, 153 with HAP) were enrolled. Bacterial pathogens were identified in 62 patients (40.5%) with HCAP and 92 patients (59.8%) with HAP (P<0.001). Streptococcus pneumoniae was more common in HCAP patients (HCAP 7.8% [12/154], HAP 0.7% [1/153], P=0.002), whereas methicillin-resistant Staphylococcus aureus (HCAP 7.1% [11/154], HAP 19.0% [29/153], P=0.002) and Acinetobacter baumanii (HCAP 2.6% [4/154], HAP 16.3% [25/153], P<0.001) were more common in HAP patients. The distributions of other multidrug-resistant pathogens, including Pseudomonas aeruginosa (HCAP 10.4% [16/154], HAP 11.1% [17/153], P=0.856) and extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (HCAP 1.3% [2/154], HAP 3.9% [6/153], P=0.173) were not significantly different. The 28-day mortalities of HCAP patients and HAP patients were 37.7% (58/154) and 33.3% (51/153) (P=0.475), respectively.
Conclusion: Our results showed that the distributions of bacterial etiology between HCAP and HAP were significantly different. It suggests that optimal strategy for empirical antibacterial treatment should be further specified in severe HCAP and HAP.
[Show abstract][Hide abstract] ABSTRACT: The role of viruses in pneumonia in adults and the impact of viral infection on mortality have not been elucidated. Previous studies have significant limitations in that they relied predominantly on upper respiratory specimens.
To investigate the role of viral infection in adult patients with pneumonia requiring intensive care unit (ICU) admission.
A retrospective analysis of a prospective cohort was conducted in a 28-bed medical ICU. Patients with severe community-acquired pneumonia (CAP) or healthcare-associated pneumonia (HCAP) were included in the study.
A total of 198 patients (64 with CAP, 134 with HCAP) were included for analysis. Of these, 115 patients (58.1%) underwent bronchoscopic bronchoalveolar lavage (BAL), 104 of whom were tested for respiratory viruses by BAL fluid reverse-transcription polymerase chain reaction (RT-PCR). Nasopharyngeal specimen RT-PCR was performed in 159 patients (84.1%). Seventy-one patients (35.9%) had a bacterial infection, and 72 patients (36.4%) had a viral infection. Rhinovirus was the most common identified virus (23.6%), followed by parainfluenza virus (20.8%), human metapneumovirus (18.1%), influenza virus (16.7%), and respiratory syncytial virus (13.9%). Respiratory syncytial virus was significantly more common in the CAP group (CAP, 10.9%; HCAP, 2.2%; P = 0.01). The mortalities of patients with bacterial infections, viral infections, and bacterial-viral coinfections were not significantly different (25.5, 26.5, and 33.3%, respectively; P = 0.82).
Viruses are frequently found in the airway of patients with pneumonia requiring ICU admission and may cause severe forms of pneumonia. Patients with viral infection and bacterial infection had comparable mortality rates.
Full-text · Article · Jun 2012 · American Journal of Respiratory and Critical Care Medicine