Etiology of Severe Pneumonia in the Very Elderly

Abstract

The etiology of severe pneumonia requiring mechanical ventilation in the very elderly has been imprecise because of lack of comprehensive studies and low yield of diagnostic approach. Overall, 104 patients 75 yr of age and older with severe pneumonia were studied prospectively at two university-affiliated hospitals. Microbial investigation included blood culture, serology, pleural fluid, and bronchoalveolar secretions. Streptococcus pneumoniae (14%), gram-negative enteric bacilli (14%), Legionella sp. (9%), Hemophilus influenzae (7%), and Staphylococcus aureus (7%) were the predominant pathogens in community-acquired pneumonia (CAP). Staphylococcus aureus (29%), gram-negative enteric bacilli (15%), Streptococcus pneumoniae (9%), and Pseudomonas aeruginosa (4%) accounted for most isolates of nursing home-acquired pneumonia (NHAP). The case fatality rate was 55% (53% for CAP and 57% for NHAP; p > 0.5). Activity of Daily Living (ADL) Index, pulmonary, endocrine and central nervous system (CNS) comorbidities were associated with distinct microbial etiology. By multivariate analysis, hospital mortality was associated independently with 24-h urine output (odds ratio [OR], 5.6; 95% confidence interval [CI], 2.5 to 7.9; p < 0.001), septic shock (OR, 4.3; 95% CI, 1.9 to 8.9; p = 0.0059), radiographic multilobar involvement (OR, 3.7; 95% CI, 1.8 to 15.6; p = 0.02), and inadequate antimicrobial therapy (OR, 2.6; 95% CI, 1.4 to 23.9; p = 0.034). Further studies should focus on identifying effective antimicrobial regimens in randomized trials.

Characteristics and disease severity of healthcare-associated pneumonia among patients in a hospital in Kitakyushu, Japan

“…It strongly suggested that a lower serum albumin level is related with elderly age and lower performance status of patients with NHAP [16], and in other study of NHAP, poor functional status has been also correlated with the presence of MDR pathogens [18]. We did not investigate patients' performance status in this study; however, performance status may be a potential prognosis factor for patients with HCAP.…”

“…We did not find significant different mortality between HCAP and CAP in this study (21.4% vs. 10.0%, respectively: p=0.3544, data not shown), however, lower serum albumin was related with mortality in patients with HCAP (P<0.0308, data not shown). Malnutrition may be one of the most important factors that affects prognosis apart from being a risk factor for pneumonia [17][18].…”

Severe community-acquired pneumonia: assessment of microbial aetiology as mortality factor

“…It is noteworthy to point out that the crude mortality of S. pneumoniae was equal in the study by MOINE et al [9] and the present study (35%). Some authors have focused on the potential severity of some bacteriological species (Pseudomonas aeruginosa) in nosocomial pneumonia [35,36], or in CAP [6,37] when structural lung diseases are present (bronchiectasis) [38]. In CAP, the pathogens generally implicated in severe cases have failed to demonstrate a role in poor outcome.…”

How deadly is seasonal influenza-associated pneumonia? The German Competence Network for Community-Acquired Pneumonia

“…In a study addressing elderly patients with severe CAP, the incidence of influenza was found to be trivial, however, the bias of serology-based detection has to be taken into account [17]. As far as reported, mortality was always very low.…”