Sputum culture and antibiotic resistance in elderly inpatients with exacerbation of chronic obstructive pulmonary disease at a tertiary geriatric hospital in southern Vietnam

OBJECTIVE

To determine the rate of positive culture sputum and related factors as well as the microorganism features and antibiotic susceptibility of pathogens in elderly inpatients with exacerbation of chronic obstructive pulmonary disease (COPD) in Thong Nhat Hospital, Vietnam.

METHODS

This cross-sectional study included elderly patients admitted to the hospital because of exacerbation of COPD. Data of their medical history, symptoms and signs were collected, and the patients were instructed to collect sputum sample. A positive culture was identified with the growth of ≥ 10⁵ colony-forming units per milliliter. Antibiotic susceptibility testing was performed according to the European Committee on Antimicrobial Susceptibility Testing.

RESULTS

There were 167 participants (mean age: 77.5 ± 8.8 years, 87.4% male). The culture-positive rate was 25.1%. A higher proportion of positive culture was among participants with purulent sputum (p = 0.029) and with severe and very severe airflow obstruction (p = 0.005). Three most common agents were Acinetobacter baumannii (24.4%), Klebsiella pneumoniae (22.2%), and Pseudomonas aeruginosa (15.6%). Despite high resistance to almost other antibiotics (> 50% resistance), Acinetobacter baumannii and Pseudomonas aeruginosa were sensitive to colistin, tobramycin, and gentamicin (> 80% susceptibility). Klebsiella pneumoniae was highly sensitive to almost common antibiotics (> 80% susceptibility). Among Gram-positive pathogens, methicillin-resistant Staphylococcus aureus (MRSA) was completely sensitive to vancomycin, teicoplanin, and linezolid.

CONCLUSION

The sputum culture-positive rate in this study was not high. Most prevalent isolated pathogens were Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Acinetobacter baumannii and Pseudomonas aeruginosa were sensitive to tobramycin, gentamicin, and colistin. Commonly used antibiotics remained effective against Klebsiella pneumoniae. MRSA was sensitive to vancomycin, teicoplanin, and linezolid.

Systematic review on the effects of physical exercise on cellular immunosenescence-related markers - An update

Immunosenescence is a remodeling of the immune system occurring with aging that leads to an increased susceptibility to auto-immunity, infections and reduced vaccination response. A growing consensus supports the view that physical exercise may counteract immunosenescence and improve the immune response. Unfortunately, evidence regarding the effects of exercise on markers of cellular immunosenescence lacked uniformity at the time of an extensive literature review in 2016. Moreover, exercise-induced effects in older adults were underrepresented compared to young adults or completely lacking, such as for senescent T-cells and apoptosis of T-lymphocytes. The aim of this systematic literature study was to collect and appraise newly available data regarding exercise-induced changes on immunosenescence-related markers of immune cells and compare this against data that was already available in 2016. Systematic reviewing of newly available data in the field of exercise immunology provides additional evidence for the effect of exercise on immunosenescence-related cellular markers. Importantly, this review provides evidence for the effect of long-term exercise on senescent T-lymphocytes in older adults. Additionally, newly retrieved evidence shows an acute exercise-induced mobilization of naïve and memory cells in older adults. In general, data regarding long-term exercise-induced effects in older adults remain scarce. Noteworthy was the high number of articles describing exercise-induced effects on regulatory T-cells. However exercise-induced effects on this cell type are still inconclusive as some articles reported an exercise-induced up- or downregulation, while others reported no effects at all. Numerous studies on Natural Killer cell counts did not provide uniformity among data that was already available. Recent data regarding dendritic cells mostly described an increase after exercise. Overall, our literature update highlights the major influence of the type and intensity of exercise on immunosenescence-related markers, especially in older adults.

Strength Endurance Training but Not Intensive Strength Training Reduces Senescence-Prone T Cells in Peripheral Blood in Community-Dwelling Elderly Women

Aging is characterized by a progressive decline in immune function known as immunosenescence. Although the causes of immunosenescence are likely to be multifactorial, an age-associated accumulation of senescent T cells and decreased naive T-cell repertoire are key contributors to the phenomenon. On the other hand, there is a growing consensus that physical exercise may improve immune response in aging. However, the optimum training modality required to obtain beneficial adaptations in older subjects is lacking. Therefore, we aimed to investigate the effects of exercise modality on T-cell phenotypes in older women. A total of 100 women (aged ≥ 65 years) were randomized to either intensive strength training (80% of one-repetition maximum ), strength endurance training (40% one-repetition maximum), or control (stretching exercise) for 2-3 times per week during 6 weeks. The T-cell percentages and absolute counts were determined using flow cytometry and a hematology analyzer. C-reactive protein was measured using immunonephelometry. We report for the first time that 6 weeks of strength endurance training significantly decreased the basal percentage and absolute counts of senescence-prone T cells, which was positively related to the number of training sessions performed. Conceivably, training protocols with many repetitions-at a sufficiently high external resistance-might assist the reduction of senescence-prone T cells in older women.

Six weeks of strength endurance training decreases circulating senescence-prone T-lymphocytes in cytomegalovirus seropositive but not seronegative older women

Background

Ageing is associated with a decline in immune function termed immunosenescence. This process is characterized amongst others by less naive T-cells and more senescent phenotypes, which have been implicated in the pathogenesis of many age-related diseases. Thus far, reports regarding the long-term adaptation effects of exercise on T-cell phenotypes are scant and largely equivocal. These inconsistencies may be due to potential contributors to immunosenescence, particularly cytomegalovirus infection, which is considered a hallmark of T-cell senescence. Therefore, we sought to investigate the impact of cytomegalovirus serostatus on the distribution of peripheral T-cell subsets following long-term exercise in older women.

Methods

One hundred women (aged 65 years and above) were randomized to 3 times/weekly training at either intensive strength training (3 × 10 repetitions at 80% of one-repetition maximum, n = 31), strength endurance training (2 × 30 repetitions at 40% of one-repetition maximum, n = 33), or control (passive stretching exercise, n = 36) for 6 weeks. All training sessions were supervised by trained instructors to minimize the risk of injury and to ensure that the participants adhered to the training protocol throughout the entire range of motion. The T-cell percentages and absolute blood counts were determined before and after 6 weeks (24 h–48 h after the last training session) using flow cytometry and a haematology analyser. Cytomegalovirus antibodies were measured in serum using Architect iSystem and cytomegalovirus serostatus was balanced in the three intervention groups. C-reactive protein was measured using immunonephelometry.

Results

We report for the first time that 6 weeks of strength endurance training significantly decreased senescence-prone T-cells along with a small increase in the number of CD8– naive T-cells in blood. The absolute counts of senescent-like T-cells decreased by 44% (from 26.03 ± 35.27 to 14.66 ± 21.36 cells/μL, p < 0.01) and by 51% (from 6.55 ± 12.37 to 3.18 ± 6.83 cells/μL, p < 0.05) for the CD8+ and CD8– T-cell pools, respectively. Intriguingly, these changes were observed in cytomegalovirus seropositive, but not cytomegalovirus seronegative individuals.

Conclusions

In conclusion, the present study shows that strength endurance training leads to a reduction in circulating senescence-prone T-cells in cytomegalovirus seropositive older women. It remains to be established if monitoring of peripheral senescence-prone T-cells may have utility as cellular biomarkers of immunosenescence.

Electronic supplementary material

The online version of this article (10.1186/s12979-019-0157-8) contains supplementary material, which is available to authorized users.