Agent Of Pneumonia Research Articles

Mycoplasma pneumoniae – modern data on the structure, molecular biology and epidemiology of the pathogen

Mycoplasma pneumoniae is a common etiologic agent of respiratory tract infections and community-acquired pneumonia (CAP) in children and adults. Recently, much new data on this pathogen, its molecular biology, cytoadherence and epidemiology have been accumulated. This review describes in detail the features of the microorganism and the pathogenesis of the diseases caused, clinical manifestations, provides data on the epidemiology of the incidence of respiratory mycoplasmosis and CAP caused by this microorganism in the world, discusses the issues of asymptomatic carriage, considers the problems of laboratory diagnosis, antibiotic therapy and antibiotic resistance of the pathogen.

Differential diagnosis of community-acquired bacterial pneumonia and viral lung injury in hospitalized adults

Objective. Identification of clinical, laboratory, and instrumental factors more common in bacterial pneumonia compared to viral pneumonia, including COVID-19. Materials and Methods. This retrospective case-control study included hospitalized adults with communityacquired bacterial pneumonia and viral lung injury, including COVID-19. Patients were included taking into account age, gender, hospitalization department (general ward or ICU), and Charlson comorbidity index. Clinical, demographic, laboratory, and instrumental data on admission were studied. Unadjusted odds ratios (OR) were calculated using univariate logistic regression (for quantitative indicators) and contingency table analysis (for categorical indicators); adjusted OR were calculated using multivariate logistic regression. Results. The community-acquired bacterial pneumonia group included 100 patients, and the viral lung injury group included 300 patients. Among the causative agents of bacterial pneumonia, Streptococcus pneumoniae was the most common; in the group of viral lung injury, SARS-CoV-2 predominated. In multivariate analysis, the presence of chills (OR and 95% CI: 22.1 [6.8–72.6], p < 0.001), unilateral infiltration according to X-ray or computer tomography (OR and 95% CI: 17.9 [ 7.3–44.1], p < 0.001), altered level of consciousness (OR and 95% CI: 3.2 [1.2–8.5], p = 0.019), use of vasopressors in the first 24 hours of hospitalization ( OR and 95% CI: 11.8 [2.5–55.9], p = 0.002), higher heart rate (OR and 95% CI: 9.1 [2.2–38.6], p = 0.003) and neutrophil/lymphocyte index (OR and 95% CI: 1.4 [1.1–1.9], p = 0.021), as well as the absence of fatigue (OR and 95% CI: 0.2 [0.08–0.40], p < 0.001) and lower total protein (OR and 95% CI: 0.2 [0.02–1.00], p = 0.049) are more typical for bacterial pneumonia compared to viral lung injury. Conclusions. Differential diagnosis between community-acquired bacterial pneumonia and viral lung injury, including COVID-19, requires a comprehensive analysis of clinical, laboratory, and instrumental data.

Effectiveness of curcumin-based antimicrobial photodynamic therapy against Staphylococcus aureus.

This study investigated the effectiveness of curcumin-based antimicrobial photodynamic therapy (aPDT) against Staphylococcus aureus (S. aureus), the causative agent of ventilator-associated pneumonia. Curcumin was added to S. aureus culture medium at concentrations of 25, 2.5, and 0.25 µM. After 60 min (20-25°C), each culture was irradiated for 1 and 3 min, and viable bacteria were counted. Curcumin (25 µM) was also added to a bacterial suspension with D-mannitol and sodium azide; microbial counts were determined after irradiation for 3 min. S. aureus was significantly reduced in the 1-min (P = 0.043) and 3-min (P = 0.011) irradiation groups in comparison to the 0-min irradiation group with 25 µM curcumin. No significant differences were observed between the curcumin alone group and the curcumin plus D-mannitol or sodium azide group. The findings of this study indicate that prolonged exposure (≥1 min) of S. aureus to LED in 25 μM curcumin solution induces cell wall injury. Curcumin-based aPDT as an adjunct to conventional oral care, employing existing dentistry equipment, offers a promising approach that does not rely on antimicrobial drugs or allows the emergence of resistant bacterial strains. This suggests its potential role in future strategies aimed at preventing ventilator-associated pneumonia.

First report of Mycobacteroides abscessus subsp. massiliense and Erysipelothrix rhusiopathiae as causative agents of pneumonia and hepatitis in a boa (Boa constrictor)

An adult boa with acute epistaxis, without other clinical signs, was found dead in its terrarium. Macroscopic examination of the specimen revealed multiple yellow foci in the lung and liver. Microscopic findings included severe and multifocal granulomas as well as vasculitis, hemorrhages and thrombosis in liver and lungs, with the presence of intralesional Gram positive and acid-fast bacilli. PCR end point analysis and sequencing using total DNA extracted from formalin-fixed paraffin-embedded samples of liver and lungs identified Mycobacteroides abscessus subsp massiliense and Erysipelothrix rhusiopathiae. Mycobacteria are organisms that can affect a wide range of animals, including reptiles. In snakes, reports are rare and mycobacterial species are highly variable. Erysipelothrix rhusiopathiae is a pathogenic bacillus related to multiple organ disorders, which until now has not been reported in boas. This report describes the first case report of Mycobacteroides abscessus subsp. massiliense and Erysipelothrix rhusiopathiae detection in a boa.

Developing a rapid test to detect causative agents of pneumonia in calves

Developing a rapid test to detect causative agents of pneumonia in calves

176. Evaluation of the Predictive Value of Methicillin-Resistant Staphylococcus aureus (MRSA) Nares Polymerase Chain Reaction (PCR) Screening within Hospitalized Patients

Abstract Background While MRSA nares PCR screening utilization has established evidence for de-escalation of anti-MRSA agents in pneumonia, its utility in other sites of infection is not well studied. The purpose of this study was to evaluate the utility of MRSA nares PCR screening within a wide range clinical specimens and its impact on antimicrobial stewardship. Methods This retrospective study was conducted at a 446-bed academic medical center. Patients ≥ 18 years old with an in-house MRSA nares PCR ordered between 1 November 2021 and 1 February 2022 were included in the primary analysis. Negative predictive value (NPV), positive predictive value (PPV), sensitivity, and specificity were calculated using cultures obtained within 7 days of nares screening. Vancomycin duration, de-escalation, and incidence of acute kidney injury were collected pre- and post- implementation of the in-house MRSA PCR screening. The pre-intervention cohort observed patients admitted from 1 November 2020 to 1 February 2021 screened by send out MRSA nares PCR. Results At baseline, patients were a mean age of 55 years old, 55% black, and required ICU care in 50% of cases. A total of 665 cultures from 308 patients were included in the primary analysis (131 respiratory, 282 blood, 154 urine, 61 wound, 22 sterile fluid, 15 bone, and 12 spinal fluid specimens). The overall NPV of the MRSA nares PCR screening was 99.8% and the PPV was 21.1%. The sensitivity and specificity were 96.8% and 81.67%, respectively. Duration of vancomycin was a median of 3 days in both the pre- and post- intervention cohorts. However, rates of vancomycin de-escalation increased at day 3 from 31.5% to 48.1% and at day 5 from 69.9% to 80.0% post implementation on an in-house MRSA PCR screening. Incidence of acute kidney injury decreased from 45.2% to 21.6%. Conclusion Based on its high NPV among cultures of different sites, MRSA nares PCR screening may be utilized to de-escalate anti-MRSA agents within tertiary care facilities. Disclosures All Authors: No reported disclosures.

Experimental Infection with Mycoplasma hyopneumoniae Strain 232 in Swine Influences the Lower Respiratory Microbiota.

Mycoplasma (M.) hyopneumoniae, the etiological agent of swine enzootic pneumonia, has been reported to increase the susceptibility to secondary infections and modulate the respiratory microbiota in infected pigs. However, no studies have assessed the influence of M. hyopneumoniae on the respiratory microbiota diversity under experimental conditions. Therefore, this study evaluated the impact of M. hyopneumoniae infection on the respiratory microbiota of experimentally infected swine over time. To accomplish this, 12 weaned pigs from a M. hyopneumoniae-free farm were divided into two groups: M. hyopneumoniae strain 232 infected (n = 8) and non-infected (n = 4). The first group received 10 mL of Friis medium containing 107 CCU/mL of M. hyopneumoniae while the control group received 10 mL of sterile Friis medium. Inoculation of both groups was performed intratracheally when the animals were 35 days old (d0). At 28 days post-inoculation (dpi) and 56 dpi, 4 infected animals plus 2 controls were humanely euthanized, and biopsy samples of nasal turbinates (NT) and bronchus-alveolar lavage fluid (BALF) samples were collected. The DNA was extracted from the individual samples, and each group had the samples pooled and submitted to next-generation sequencing. Taxonomic analysis, alpha and beta diversity indexes, weighted unifrac, and unweighted unifrac distances were calculated. A high relative frequency (99%) of M. hyopneumoniae in BALF samples from infected animals was observed with no significant variation between time points. The infection did not seem to alter the diversity and evenness of bacterial communities in NT, thus, M. hyopneumoniae relative frequency was low in NT pools from infected animals (28 dpi-0.83%; 56 dpi-0.89%). PCoA diagrams showed that BALF samples from infected pigs were grouped and far from the control samples, whereas NT from infected animals were not separated from the control. Under the present coditions, M. hyopneumoniae infection influenced the lower respiratory microbiota, which could contribute to the increased susceptibility of infected animals to respiratory infections.

Impact of Four Ovine TMEM154 Haplotypes on Ewes during Multiyear Lentivirus Exposure.

Polypeptide variation encoded by the ovine transmembrane protein 154 gene (TMEM154) is associated with susceptibility to ovine lentivirus, the causative agent of Ovine Progressive Pneumonia (OPP) and Visna/Maedi. Our aim was to compare the four most prevalent TMEM154 haplotypes on the incidence of infection and ewe productivity during natural multiyear virus exposure. Prospective cohort studies were designed to test gene action and estimate effects of TMEM154 haplotypes encoding distinctive variant residues: K35 (“1”), I70 (“2”), ancestral (“3”), and A4del/M44 (“4”). Exposure consisted of co-mingling infected ewes at a rate greater than 30% with serological status evaluated every four months. For ewes with one or two copies of the highly susceptible haplotypes “2” and ”3”, the infection prevalence steadily increased to nearly 100% at 55 months. Haplotypes “2” and “3” were equally susceptible and dominant to haplotype “1”. A difference was not detected (p < 0.53) in the magnitude of effect with haplotype combinations of “1” and ”4”. The ewe infection prevalence with “1,1”; “1,4”; and “4,4” was 10% to 40% at 55 months. The latter suggested that two copies of the K35 amino acid substitution (“1”) were as effective as a homozygous TMEM154 “knockout” with the frame-shift deletion mutation (“4”) in reducing infection susceptibility. When considering ewe reproductive performance, a difference was not detected when comparing haplotypes “2”, and “3” to each other, or “1” and “4” to each other. Our study indicated that ewes with two copies of the severely truncated versions of TMEM154 (“4,4”) had normal lamb productivity. Without complete understanding of the natural function of TMEM154 our recommendations to producers interested in using TMEM154 selection to reduce their flock’s genetic predisposition to OPP are encouraged to increase the frequency of TMEM154 haplotype K35 (“1”) since it encodes a full-length protein with minimal difference to the ancestral polypeptide.

Screening for eukaryotic motifs in Legionella pneumophila reveals Smh1 as bacterial deacetylase of host histones

ABSTRACT Legionella pneumophila (L.p.) is a bacterial pathogen which is a common causative agent of pneumonia. In humans, it infects alveolar macrophages and transfers hundreds of virulence factors that interfere with cellular signalling pathways and the transcriptomic landscape to sustain its own replication. By this interaction, it has acquired eukaryote-like protein motifs by gene transfer events that partake in the pathogenicity of Legionella. In a computational screening approach for eukaryotic motifs in the transcriptome of Legionella, we identified the L.p. strain Corby protein ABQ55614 as putative histone-deacetylase and named it “suppressing modifier of histones 1” (Smh1). During infection, Smh1 is translocated from the Legionella vacuole into the host cytosol. When expressed in human macrophage THP-1 cells, Smh1 was localized predominantly in the nucleus, leading to broad histone H3 and H4 deacetylation, blunted expression of a large number of genes (e.g. IL-1β and IL-8), and fostered intracellular bacterial replication. L.p. with a Smh1 knockdown grew normally in media but showed a slight growth defect inside the host cell. Furthermore, Smh1 showed a very potent histone deacetylation activity in vitro, e.g. at H3K14, that could be inhibited by targeted mutation of the putative catalytic center inferred by analogy with eukaryotic HDAC8, and with the deacetylase inhibitor trichostatin A. In summary, Smh1 displays functional homology with class I/II type HDACs. We identified Smh1 as a new Legionella virulence factor with a eukaryote-like histone-deacetylase activity that moderates host gene expression and might pave the way for further histone modifications. IMPORTANCE Legionella pneumophila (L.p.) is a prominent bacterial pathogen, which is a common causative agent of pneumonia. In order to survive inside the host cell, the human macrophage, it profoundly interacts with host cell processes to advance its own replication. In this study, we identify a bacterial factor, Smh1, with yet unknown function as a host histone deacetylase. The activity of this factor in the host cell leads to attenuated gene expression and increased intracellular bacterial replication.

Serostatus and Epidemiological Characteristics for Atypical Pneumonia Causative Bacteria among Healthy Individuals in Medina, Saudi Arabia, a Retrospective Study.

Background: Community-acquired atypical pneumonia is generally a mild and self-limiting infection. Still, it may lead to hospitalization and progressive clinical complications in some cases, particularly among the elderly and individuals with chronic diseases. Chlamydia pneumoniae, Legionella pneumophila, and Mycoplasma pneumoniae are the community's main causative agents of atypical pneumonia. However, most published studies evaluated their incidence in the hospital setting, and little is known about their prevalence among healthy individuals. This work aims to assess the seroprevalence of these bacteria among healthy people to determine the status of immunity against these bacteria in the community. Methodology: Two hundred and eighty-three serum samples from a multicenter in Medina, Saudi Arabia, were collected in this study. Serum samples were subjected to indirect enzyme-linked immunosorbent assays (ELISAs) to detect IgG antibodies against C. pneumoniae, L. pneumophila, and M. pneumoniae to investigate the seroprevalence of these bacteria and their distribution among different genders and age groups of healthy people. Results: IgG seropositivity for at least one of the three atypical pneumonia-causative bacteria occurred in 85.8% (n= 243/283) of the sample population. IgG seropositivity for C. pneumoniae occurred in 80.6% (228/283) of the population, followed by 37.5% for L. pneumophila and 23% for M. pneumoniae (66/283). In addition, the IgG seropositivity rates for the three bacteria were observed predominantly among male participants. Furthermore, no significant difference in IgG seropositivity distribution occurred between different age groups of healthy people for C. pneumoniae,&amp;nbsp;L. pneumophila and M. pneumoniae. Conclusions: The current study found that C. pneumoniae, L. pneumophila, and M. pneumoniae tended to be highly prevalent among healthy people and more common among males than females. Additionally, their pattern of distribution among healthy individuals seemed to be predominant among young adults (aged 20-40 years), which differs from their predominant distribution among elderly patients in hospital settings (&gt;50 years).

Oral Immunization with Attenuated Salmonella Choleraesuis Expressing the P42 and P97 Antigens Protects Mice against Mycoplasma hyopneumoniae Challenge.

Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) is the etiological agent of swine enzootic pneumonia (EP), which has been associated with considerable economic losses due to reduced daily weight gain and feed efficiency. Adhesion to the cilia is important for Mhp to colonize the respiratory epithelium. Therefore, a successful vaccine must induce broad Mhp-specific immune responses at the mucosal surface. Recombinant attenuated Salmonella strains are believed to act as powerful live vaccine vectors that are able to elicit mucosal immune responses against various pathogens. To develop efficacious and inexpensive vaccines against Mhp, the immune responses and protection induced by recombinant attenuated Salmonella vaccines based on the P42 and P97 antigens of Mhp were evaluated. In general, the oral inoculation of recombinant rSC0016(pS-P42) or rSC0016(pS-P97) resulted in strong mucosal immunity, cell-mediated immunity, and humoral immunity, which was a mixed Th1/Th2-type response. In addition, the levels of specific IL-4 and IFN-γ in the immunized mice were increased, and the proliferation of lymphocytes was also enhanced, confirming the production of a good cellular immune response. Finally, both vaccine candidate strains were able to improve the weight loss of mice after a challenge and reduce clinical symptoms, lung pathological damage, and the inflammatory cell infiltration. These results suggest that the delivery of protective antigens with recombinant attenuated Salmonella vectors may be an effective means by which to combat Mhp infection. IMPORTANCE Mhp is the main pathogen of porcine enzootic pneumonia, a highly infectious and economically significant respiratory disease that affects pigs of all ages. As the target tissue of Mhp infections are the mucosal sites of the respiratory tract, the induction of protective immunity at the mucosal tissues is the most efficient strategy by which to block disease transmission. Because the stimulation of mucosal immune responses is efficient, Salmonella-vector oral vaccines are expected to be especially useful against mucosal-invading pathogens. In this study, we expressed the immunogenic proteins of P42 and P97 with the attenuated Salmonella Choleraesuis vector rSC0016, thereby generating a low-cost and more effective vaccine candidate against Mhp by inducing significant mucosal, humoral and cellular immunity. Furthermore, rSC0016(pS-P42) effectively prevents Mhp-induced weight loss and the pulmonary inflammation of mice. Because of the effectiveness of rSC0016(pS-P42) against Mhp infection in mice, this novel vaccine candidate strain shows great potential for its use in the pig breeding industry.

ROLE OF TOCILIZUMAB IN PATIENTS WITH MODERATE-TO-SEVERE COVID-19 PNEUMONIA

Objectives: Cytokine release syndrome (CRS) is believed to be responsible for death in COVID-19. Tocilizumab is an interleukin (IL)-6 receptor antagonist, IL-6 being identified as a major component of the CRS cascade. The objective of the study was to determine if tocilizumab can prevent mortality and morbidity in moderate-to-severe COVID-19 pneumonia. Methods: Patients admitted to the ICU between the time period of June 2020–August 2020 were included in this retrospective and cohort study conducted at GCS medical college, hospital and research center. Patients had to be more than 18 years of age and were required to have a positive reverse transcription polymerase chain reaction report for COVID-19. After applying the inclusion/exclusion criteria, 119 patients were considered for final analysis. Tocilizumab was administered as a single dose of 8 mg/kg in 22 patients. Rest of the patients received standard of care regime. The primary outcome was either discharge or death of the patients and the requirement of invasive mechanical ventilation during their hospital stay. The secondary outcome was the length of hospital stay. Appropriate demographic, clinical, and laboratory data were documented. Statistical analysis was done with appropriate clinical tests with significance set at p&lt;0.05. Results: Tocilizumab significantly reduced deaths in patients as well as the need for mechanical ventilation with NNT=3 and 5, respectively. The same held true even when the data were adjusted for age, gender, and number of comorbidities. Number of comorbidities had a negative association with mortality and need for mechanical ventilation irrespective of administration of tocilizumab as evidenced by multivariable logistic regression. There was no effect of tocilizumab in shortening the hospital stay in patients. Conclusion: Tocilizumab seems to be a promising agent for the treatment of moderate to severe COVID-19 pneumonia and similar agents hold promise for any similar future emerging infections.

Role of Lipid Nanoparticles in COVID-19 in Repurposing Drugs and Vaccines

Background:The spread of new coronavirus 2019, the causative agent of viral pneumonia documented in Wuhan, brought a recent public health crisis globally. The best solution to overcome this pandemic is developing suitable and effective vaccines and therapeutics. However, discovering and creating a new drug is a lengthy process requiring rigorous testing and validation.Objective:Despite many newly discovered and old repurposed COVID-19 drugs under clinical trial, more emphasis should be given to research on COVID-19 NPs-based medicines, which could improve the efficacy of antiviral drugs to reduce their side effects. The use of NPs as carriers can reduce the frequency and duration of drug ingestion, enhance approved antiviral therapeutics' effectiveness, and overcome their limitations, such as low bioavailability. Besides, they can play a crucial role in fighting against the COVID-19 pandemic. In this regard, nanotechnology provides opportunities to develop new strategies for preventing, diagnosing, and treating COVID-19.Conclusion:This review highlighted the importance of NMs-based technical solutions in antiviral drugs for testing against the SARS-CoV-2 virus emergencies in the form of nanotherapeutics.

Cytokine Profiling in Influenza A Virus and Staphylococcal (Co-)Infections

Abstract Influenza A virus and Staphylococcus aureus are common causative agents of pneumonia. Co-infections with these two pathogens frequently occur and are characterized, among others, by higher morbidity and mortality due to hyper-inflammation of the lungs. Here, we aimed to profile systemic and local cytokine composition at early acute stages of pneumonia in a murine model. All mice recovered from single influenza A virus and/or staphylococcal infections. In contrast, co-infections led to a severe clinical outcome. While distinct cytokine patterns were detected in lungs of single-pathogen-infected animals, co-infections combined both virus- and bacteria-driven responses. However, analyses of infected human primary monocytic cells as well as bronchial epithelial cells did not reflect murine profiles. Based on infectious dose, mainly bacteria-driven responses were noted. The impact of single cells to cytokine composition of the lungs and translation of murine studies to humans remains uncertain and warrants further studies.

Transmission dynamics of Q fever in French Guiana: A population-based cross-sectional study

Q fever is a zoonosis caused by Coxiella burnetii which is among the major agents of community-acquired pneumonia in French Guiana. Despite its relatively high incidence, its epidemiology in French Guiana remains unclear, and all previous studies have considered transmission from livestock unlikely, suggesting that a wild reservoir is responsible for transmission. A country-wide seroprevalence survey of 2697 participants from French Guiana was conducted. Serum samples were tested for phase II IgG antibodies by ELISA and indirect immunofluorescence assays (IFAs). Factors associated with Q fever were investigated, and a serocatalytic model was used to reconstruct the annual force of infection. The overall weighted seroprevalence was estimated at 9.6% (95% confidence interval (CI): 8.2%-11.0%). The model revealed constant, low-level circulation across French Guiana, particularly affecting middle-aged males (odds ratio (OR): 3.0, 95% credible interval (CrI): 1.7-5.8) and individuals living close to sheep farms (OR: 4, 95% CrI: 1.5-12). The overall annual number of cases was estimated at 579 (95% CrI: 492-670). In the region around Cayenne, the main urban municipality, the high seroprevalence was explained by an outbreak that may have occurred between 1996 and 2003 and that infected 10% (95% CrI: 6.9%-14%) of the population and males and females alike. This study reveals for the first time Q fever dynamics of transmission and the role of domestic livestock in transmission in French Guiana and highlights the urgent need to reinforce Q fever surveillance in livestocks of the entire Guianese territory. This study was supported by the "European Regional Development Fund" under EPI-ARBO grant agreement (GY0008695), the "Regional Health Agency of French Guiana" and the "National Center of Spatial Studies". The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Some features of the course of viral pneumonia in obesity

Intriduction. In the last decade, conflicting data has appeared that the presence of obesity in patients with several diseases not only does not worsen, but even improves their prognosis, which is called the “obesity paradox”. The role of elevated body mass index in patients with coronavirus pneumonia (COVID-19) remains unclear.Aim. To study the features of the course of pneumonia in young and middle-aged men depending on the body mass index.Materials and methods. A retrospective analysis has investigated and it included 451 young and middle-aged men who underwent inpatient treatment for COVID-19 pneumonia. Patients were randomized according to body mass index into groups: normal nutrition (N), overnutrition (On), obesity (Ob). Clinical and laboratory parameters were assessed using statistical analysis.Results and discussion. In patients with obesity, the causative agent of pneumonia was detected in 91.9% of cases, in contrast to group N (65.75%). At the onset of pneumonia, group Ob differed significantly from group N in terms of erythrocyte sedimentation rate (17 versus 9 mm/h), C-reactive protein (18.3 versus 7.2 mg/l), D-dimer (304 versus 230 ng/ml), glycemia (6.2 versus 5.2 mmol/l), lymphocytes 9 (1.3 versus 1.5 × 109/l). In the dynamics in the group Ob, in comparison with the group N, there is a higher level of platelets (307 versus 1 × 109/l), neutrophils (6.3 versus 3.7 × 109/l), monocytes (0.8 versus 0.6 × 109/l) and a smaller number of lymphocytes (1.4 versus 2.0 × 109/l). It was revealed that the lymphocytic index and the index of the ratio of lymphocytes to monocytes in dynamics significantly increase in group N (from 0.5 to 0.7 and from 3.5 to 4.5, respectively), in group On only the lymphocyte index significantly increases (from 0.4 to 0.5), in the obesity group they do not change (from 0.4 to 0.5 and 3 from.0 to 2.7, respectively). The greatest need for respiratory support had group Ob (21.1%) in comparison with GNP (6.0%).Conclusions. The level of adipose tissue in the body has a direct impact on the course of pneumonia.

Nursing research on a new silver-based antibacterial agent for pneumonia.

As a highly contagious bacterium, pneumonia can cause a series of respiratory diseases, and its treatment has become a concern of people. This study mainly discusses the nursing research of a new silver-based antibacterial agent in the treatment of pneumonia. The following procedures were performed: (1) a sterilized expectoration suction device was inserted into the nasopharynx (7–8 cm), and the nasopharyngeal secretions were suck by controlling the pressure of the suction device; and (2) the catheter was washed with 2 mL of sterilized physiological saline, and the sample was immediately sent to the laboratory for bacterial culture of the lower airway and respiratory secretions to determine viral antigens. The drug resistance coefficient of the lysozyme, benzoate, and pneumonia bacteria is 4.5–26.8%. In addition, the fourth generation sefalos posephin and pneumonia bacteria presented drug sensitivity, and the drug resistance coefficient is 13.1–33.3%. The sensitivity to the new silver-based antimicrobial agent and lopenem is 100%. The sensitivity of other germs is between 2 and 5%. The results of the study indicate that the antibacterial properties of the new silver-based antibacterial agent increase with the degree of amino acid substitution of the same sample concentration. The new silver-based antibacterial agent has excellent antibacterial properties against Klebsiella pneumoniae.

Clinical Efficacy, Antibiotic Resistance Genes, Virulence Factors and Outcome of Hospital-Acquired Pneumonia Induced by Klebsiella pneumoniae Carbapenemase 2-Producing with Tigecycline Treatment in the ICU.

PurposeTigecycline is an agent for carbapenemase-producing Klebsiella pneumonia (KPC-KP), given its penetration into lung tissues. Our study focused on the molecular and clinical efficacy of tigecycline for hospital-acquired pneumonia (HAP) in the ICU.Patients and MethodsA retrospective cohort study of 52 adult KPC-KP HAP patients by searching hospital medical records from January 2018 to December 2020 was established to investigate the epidemiology of KPC-KP infections for tigecycline treatment and the associated clinical efficacy of tigecycline. The KPC-KP isolates underwent multilocus sequence typing. Molecular typing, antimicrobial resistance, and virulence profiling were also analyzed by whole-genome sequencing of KPC-KP.ResultsAmong 52 patients with KPC-KP, the ICU mortality rate was 14/52 (27%), and there was no significant statistical difference in mortality between the effective group and failure group (p = 0.754). However, the duration of tigecycline was statistically different between the two groups of patients (14.4 vs 10 days, p=0.046). The total bacterial clearance rate was 6/52 (11.5%). There was no significant statistical difference in both groups (p=0.416). Antibiotic resistance genes (aac3iia) and virulence gene (AREO-iutA, Capsule-wzc) were negatively correlated with clinical efficacy (p = 0.011, OR = 1.237).ConclusionsBlakpc was the main carbapenemase in all K. pneumoniae strains. ST11-KL64 KPC-KP was the most common virulence factors in KPC-KP isolates. This study suggested that antibiotic resistance genes (aac3iia) and virulence gene (AREO-iutA, Capsule-wzc) were independent mortality risk factors for patients with Klebsiella pneumoniae carbapenemase-2 producing K. pneumoniae infections, when during the tigecycline treatment. Molecular analysis of K. pneumoniae may provide an option when choosing the antimicrobial treatment.

Identification of Mycoplasma pneumoniae-associated pneumonia cases among hospitalized patients using CLART® microarray technology.

ObjectivesCommunity-acquired pneumonia (CAP) is a global health condition that affects populations from all age groups. The laboratory identification of Mycoplasma pneumoniae as a causative agent of CAP is challenging because of its atypical and fastidious nature. Therefore, this study assessed the diagnostic potential of PneumoCLART bacteria® in identifying M. pneumoniae as a causative agent of pneumonia in hospitalized adults.MethodsThis prospective study used a cross-sectional approach to assess the diagnostic potential of PneumoCLART bacteria® for detecting M. pneumoniae in sputum samples procured from 27 patients with pneumonia who required hospitalization.ResultsThe PneumoCLART bacteria® results illustrated that 7 of 27 patients with pneumonia were positive for M. pneumoniae (26%). However, the quality of sputum varied among the M. pneumoniae-positive and M. pneumoniae-negative samples. Fifty percent of the specimens obtained from patients positive for M. pneumoniae were saliva-contaminated and unsuitable for analysis.ConclusionsBecause the leukocyte count was low and sputum specimens were saliva-contaminated, these findings require further validation to prove the utility of CLART® microarray technology for the identification of M. pneumoniae in pneumonia-positive patients. Conclusively, this prospective study included a small number of clinical samples, which likely affected its outcomes.

Evaluating linezolid dose regimens against methicillin-resistant Staphylococcus aureus based on renal function in populations with different body weight.

Linezolid is an alternative first-line agent for MRSA pneumonia. This study assessed whether dose adjustments of linezolid against methicillin-resistant Staphylococcus aureus (MRSA) infections were needed based on renal function in populations with different body weight. Monte Carlo simulations were conducted to evaluate renal function in relation to the probability of target attainment (PTA) in three population groups with different body weight. Area under the concentration time curve (AUC)/ minimum inhibitory concentration (MIC) ratio and percentage of time above the MIC (%T > MIC) were regarded as pharmacokinetic/pharmacodynamic targets. The PTA and cumulative fractions of response (CFR) were calculated to assess the efficacy. Regarding safety, trough plasma concentration (Cmin ) > 8mg/L was used as target for toxicity. Using AUC/MIC >100 as the target pharmacodynamic (PD) index, the CFR of linezolid at the standard dose (600 mg every 12 h [q12h]) were 57.01%, 93.22%, and 99.93% in patients with normal renal function, patients with renal dysfunction and low body weight patients with renal dysfunction, respectively. Using 100%T> MIC as the target PD index, all the CFR of three population groups were more than 90% at the standard dose. The percentages of Cmin > 8mg/L at the standard dose of linezolid were 24.16%, 53.24%, and 90.10% in three population groups on day 7. The risk of thrombocytopenia of linezolid was extremely higher in low body weight patients with renal impairment when receiving standard linezolid dose compared with patients with normal renal function. 450 mg q12h and 300 mg q12h might be effective and safe against MRSA infection in patients with renal dysfunction and low body weight patients with renal dysfunction, respectively.