Antimicrobial Susceptibilities and Serotypes of Streptococcus pneumoniae Isolates from Elderly Patients with Pneumonia and Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Abstract

In the elderly, Streptococcus pneumoniae is the most common cause of pneumonia and one of the most frequently isolated pathogens in cases of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). This study was conducted to compare the pneumococcal isolates obtained during episodes of AECOPD and pneumonia in patients of >65 years old and to analyze whether in patients with AECOPD and pneumonia within a short interval, the same isolate caused both episodes. This laboratory-based study was performed between 2005 and 2008. Pneumococcal isolates from episodes of pneumonia (n ‫؍‬ 401) and AECOPD (n ‫؍‬ 398), matched one-to-one by date of isolation, were characterized. The serotypes and genotypes of other pneumococcal isolates causing pneumonia and AECOPD in the same patient were compared. In patients with pneumonia, COPD as an underlying disease was not associated with more-drug-resistant pneumococci. In contrast, isolates causing AECOPD showed higher rates of resistance than those causing pneumonia. Serotypes 1, 3, and 7F were more frequent in pneumonia. The same pneumococcus was involved in 25.7% (9/35 patients) of patients with two consecutive AECOPD episodes but in only 6.3% (2/32 patients) of COPD patients with pneumonia and exacerbation (Fisher's exact test; P ‫؍‬ 0.047). Less invasive serotypes were isolated more often in AECOPD and were more resistant to antimicrobials. The presence of a specific pneumococcal serotype in AECOPD does not predict the etiology of subsequent pneumonia.The elderly are generally accepted to be more vulnerable to infections than younger people. Infectious diseases are a major cause of morbidity and mortality in the geriatric population. Increased susceptibility to infections has been attributed not only to anatomical, physiological, and/or immunological aging but also to an increase in the prevalence of chronic diseases, especially cardiovascular and pulmonary diseases (18). Pneumococcal pneumonia is the leading cause of death attributable to infectious diseases in developed countries. To prevent pneumococcal disease in people over the age of 64 years, the 23-valent polysaccharide pneumococcal vaccine (PPV23) was introduced in our region (Basque Country, northern Spain) in autumn 2007. The 7-valent pneumococcal conjugate vaccine (PCV7) for children was introduced in Spain in June 2001, but the 13-valent conjugate vaccine (PCV13) was not introduced until June 2010.Bacterial colonization in chronic obstructive pulmonary disease (COPD) contributes to airway inflammation and modulates exacerbations. The prevalence of bacterial colonization of the airways in stable COPD is high (20,25,28). Most exacerbations are infectious, and Streptococcus pneumoniae is frequently found both in stable periods and in exacerbations. As a consequence of acute exacerbations, patients with COPD receive frequent courses of antimicrobial treatment, which has been associated directly with a higher prevalence of resistant pneumococci (2).The main aim of this study was to determine whether the ser...

Dynamics of Streptococcus pneumoniae Serotypes Causing Acute Otitis Media Isolated from Children with Spontaneous Middle-Ear Drainage over a 12-Year Period (1999–2010) in a Region of Northern Spain

“…In a study of IPD in children in our region in the same years, we found a decrease of infections due to PCV7 serotypes and an increase of serotype 19A similar to those observed for AOM [27]. However, there was no increase in the incidence of serotype 3 invasive infections in children, confirming the stronger association of serotype 3 with respiratory infections, both in the lower respiratory tract of older adults [28], [29] and AOM in children [6], [22], [30]. Genotyping analysis of serotypes 19A and 3 isolates also showed a different distribution: while serotype 3 isolates belonged to only three well-known clones (ST180, ST260, and ST1220), serotype 19A isolates showed greater heterogeneity.…”

Impaired NLRP3 Inflammasome Function in Elderly Mice during Influenza Infection Is Rescued by Treatment with Nigericin

“…Pneumonia has become an increasingly significant cause of morbidity and mortality in the aging population (44-46). Although primary influenza infection alone can lead to adverse outcomes, secondary bacterial infections during and shortly after recovery from influenza infections are more common reasons for influenza-associated illness (47).…”

Streptococcus pneumoniae Colonization Disrupts the Microbial Community within the Upper Respiratory Tract of Aging Mice

“…Despite having significantly lower carriage rates than children (3,10), colonization within the upper respiratory tract of elderly individuals often leads to the progression and development of pneumonia and invasive pneumococcal disease (11)(12)(13). Pneumonia in particular affects elderly individuals approximately four times more often than individuals under the age of 65 (14).…”