Community-acquired Pneumonia In Adults Research Articles

The U-shaped association between hemoglobin concentrations and all-cause death risk in patients with community-acquired pneumonia.

The prevalence of anemia in patients with community-acquired pneumonia (CAP) has been well described. However, few studies have explored its association with short-term and long-term mortality risk in CAP patients. We aimed to investigate the associations between hemoglobin concentrations at baseline and 14-day and 1-year mortality risk in a CAP population with a large sample size. Our data originated from the Dryad database, including a dataset from the study "Incidence rate of community-acquired pneumonia in adults: a population-based prospective active surveillance study in 3 cities in South America." A total of 1463 study samples with follow-up data from the dataset were enrolled for our analysis. During the follow-up period of 3 years, the 14-day risk and 1-year mortality risk were 206 (14.08%) and 401 (27.41%), respectively, among these CAP patients. Curve analysis indicated a strong U-shaped relationship between blood hemoglobin concentrations and 14-day mortality (r = -0.191, P < .001) and 1-year mortality (r = -0.220, P < .001). The blood hemoglobin level with the lowest point of mortality risk was 14.5g/dL, suggesting that an increased hemoglobin concentration contributed to reduced 14-day and 1-year mortality risk in CAP patients when hemoglobin does not exceed 14.5g/dL even if it is within the normal clinical range. In addition, we also observed significant associations of hemoglobin with 14-day mortality risk (odds ratio [OR] = 0.817; 95% CI, 0.742-0.899 P < .001) and 1-year mortality risk (OR = 0.834; 95% CI, 0.773-0.900; P < .001), but only in participants without risk factors for health care-associated pneumonia (HCAP) rather than in participants with risk factors for HCAP. The greatest discovery is that our findings indicated a significant U-shaped relationship between hemoglobin levels and 14-day and 1-year mortality risk in CAP patients. However, a significant relationship was only discovered in subjects without risk factors for HCAP. More evidence is needed to support this finding.

The optimal antibiotic treatment duration for community-acquired pneumonia in adults diagnosed in general practice in Denmark (CAP-D): an open-label, pragmatic, randomised controlled trial

BackgroundUse of antibiotics is the main driver of antimicrobial resistance which is considered one of the biggest threats to human health. In Denmark, most antibiotics are prescribed in general practice. Acute lower respiratory tract infections, including community-acquired pneumonia (CAP), are among the most frequent indications for antibiotic prescribing. Phenoxymethylpenicillin is established as first-line treatment in general practice in Denmark. However, the treatment duration with phenoxymethylpenicillin is mostly based on traditions. Both 5 and 7 days of treatment is recommended in Danish guidelines, and when asking the general practitioners about what treatment duration, they prescribe the variation is even bigger. Several hospital-based studies have proven short course (≤ 6 days) antibiotic treatment non-inferior to long course (≥ 7 days) treatment of CAP. No evidence exists on the optimal treatment duration for CAP in non-hospitalised patients.This randomised controlled trial aim to investigate the optimal treatment duration with phenoxymethylpenicillin for CAP in adults diagnosed in general practice in Denmark.MethodsThis is an open-label, pragmatic, randomised controlled, five-arm DURATIONS trial. Participants will be recruited from at least 24 general practices in Denmark. Eligible participants are adults, with no pre-existing lung disease, presenting with symptoms of CAP, and in whom the general practitioner finds it relevant to treat with antibiotics. The study will compare treatment with phenoxymethylpenicillin 1.2 MIE q.i.d. in 3, 4, 5, 6, and 7 days.DiscussionThis study will provide evidence for the optimal antibiotic treatment duration of CAP in general practice and inform future guidelines on CAP in all countries using phenoxymethylpenicillin for the treatment of acute respiratory tract infections in adults. The results of this study might also be used to guide treatment recommendations in other countries using phenoxymethylpenicillin.Moreover, a (potential) reduction in antibiotic use might lower the development of antimicrobial resistance, increase patient treatment adherence, reduce risks of adverse events, and lower the economical expTrial registrationClinicalTrials.gov: NCT06295120. Registered 28 February 2024. The Scientific Ethics Committee for the North Denmark Region: N-20230039.

Effectiveness of the 23-Valent Pneumococcal Polysaccharide Vaccine (PPV23) in Preventing Community-Acquired Pneumonia in Adults: A Population-Based Cohort Study.

The aim was to assess the effectiveness of 23-valent pneumococcal polysaccharide vaccine (PPV23) in preventing CAP in adults. This was a population-based cohort study, followed up over 5 years (2015-2019), that included 47,768 persons aged ≥18 years assigned to three primary care centres. Data were retrospectively obtained from electronic medical records and databases. The vaccination effect was adjusted for potential confounders. Analyses were performed for the entire study population and for the ≥65 age subgroup. The annual incidence of CAP (per 103 adult inhabitants) was 3.29 overall, and 8.08 and 2.93 for vaccinated and non-vaccinated persons, respectively. The non-adjusted effect of PPV23 on CAP was evidenced by HR = 2.80 (95% CI: 2.32-3.37), and after adjusting for possible confounders, PPV23 showed no significant independent effect on CAP in the overall population (HR = 1.14; p = 0.277) or in persons aged ≥65 years (HR = 1.30; p = 0.051). No protective effect was observed in persons vaccinated <2 years previously (HR = 1.17; p = 0.514). PPV23 showed no effect in preventing CAP in adults aged ≥18 years or in the subgroup aged ≥65 years, even if vaccinated <2 years previously.

The management of community-acquired pneumonia in adults at a rural regional hospital in KwaZulu Natal

BackgroundPneumonia stands as a significant global contributor to mortality, particularly in South Africa, where it ranks as the second leading cause of death. The country’s high prevalence of HIV infection compounds this issue, significantly increasing mortality rates associated with community-acquired pneumonia (CAP).ObjectiveThis study aimed to audit CAP patient management at a regional rural hospital in KwaZulu-Natal.MethodA retrospective review of patient files from September to December 2016 was undertaken. Data extraction from clinical files, conducted according to inclusion criteria, was transferred to a data collection sheet and analyzed using SPSS version 21.ResultsThe review encompassed 124 patient files over four months, revealing that 117 (94.4%) patients were not managed by the Standard Treatment Guidelines and Essential Medicines List for South Africa. Of the patients admitted with CAP, 54% were HIV positive, and 49 (39.5%) patients succumbed to the illness. Notably, none of the patients underwent assessment using a severity score.ConclusionThe findings underscore a need for more adherence to South African guidelines for managing CAP among staff at the rural regional hospital. This leads to severe consequences, exemplified by the high mortality rate. Urgent intervention is required to incorporate severity assessment scores into pneumonia evaluations, thus enabling appropriate clinical management.ContributionThis study sheds light on the significant impact of CAP within the South African hospital context, delineating critical gaps in clinical care and emphasizing the imperative to address clinical inertia.

Comparative prospective cohort study of efficacy and safety according to dosage and administration of ceftriaxone for community-acquired pneumonia

IntroductionLimited prospective evidence has been accumulated regarding the efficacy and safety of ceftriaxone (CTRX) based on differences in dosage and administration of the drug as empiric therapy for community-acquired pneumonia (CAP). This study aimed to compare initial treatment failure, 30-day mortality, and side effects between two groups of hospitalized adult CAP patients: one receiving intravenous CTRX at 1g twice daily (1gq12hr) and the other receiving 2g once daily (2gq24hr). MethodsWe prospectively included patients with CAP admitted to our hospital between October 2010 and December 2018. We analyzed patients initially treated solely with CTRX as either 1gq12hr or 2gq24hr. The primary outcome was initial treatment failure, while secondary outcomes were 30-day mortality and side effects. Inverse probability of treatment weighting (IPTW) analysis was used to minimize biases. ResultsAmong the 457 CAP patients, 186 patients were in the 1gq12hr group and 271 patients were in the 2gq24hr group. After IPTW analysis, no significant differences in initial treatment failure rate (2.43 % vs 4.46 %, p = 0.27) or 30-day mortality rate (2.95 % vs 6.43 %, p = 0.13) were seen between groups. A small but noteworthy tendency was noted in the frequency of side effects between the two groups (1.04 % vs 4.20 %, p = 0.08) following IPTW analysis, even though the difference was not significant. ConclusionsThis study did not find any significant difference between ceftriaxone 1gq12hr and 2gq24hr regarding efficacy or safety in adult patients with CAP. However, CTRX 1gq12hr may represent a safer option in terms of side effects.

Bacterial and viral co-infections in community-acquired pneumonia in adults: a prospective study of multiple hospital centers

Bacterial and viral co-infections in community-acquired pneumonia in adults: a prospective study of multiple hospital centers

Hospital Burden of All-Cause Pneumonia and Nonbacteremic Pneumococcal Pneumonia in Adults in France Between 2013 and 2019.

Community-acquired pneumonia (CAP) is associated with significant morbidity and mortality. The study objective was to describe the hospital burden of pneumonia in the adult population in France. This retrospective study was conducted from the National Health Insurance Database. All hospitalizations for pneumonia (all-cause) between 2013 and 2019 were included. Different risk categories for patients were established based on pneumococcal vaccine recommendations by French health authorities. A total of 2 199 240 episodes of CAP were registered over the study period (annual mean, 314 177 [standard deviation, 17 818.6]); 75% occurred in patients aged ≥65 years, among whom 47% were not classified in the moderate- or high-risk categories recommended for French pneumococcal vaccination. The incidence of CAP increased with age (117.9, 395.3, and 1916.7 per 100 000 for the age groups 18-49, 50-64, and ≥65 years, respectively, in 2019). Furthermore, being at risk of pneumococcal disease resulted in more severe outcomes, including longer episode duration (mean, 14 days in low-risk vs 17 days in high-risk patients) and higher risk of referral to critical care units (from 20% to 27%), of rehospitalization up to 180 days (from 39% to 67%), of in-hospital death (from 12% to 19%), and of 1-year mortality (from 26% to 49%). This study establishes the incidence of CAP in adults in France, describes the significant burden of disease, and highlights the need for better prevention policies.

A Study on the Etiology and Clinical Manifestations of Community-Acquired Pneumonia in Adults in Western India.

Community-acquired pneumonia (CAP) is an acute lung infection affecting the alveoli in individuals who have not had recent exposure to healthcare settings. It is characterized by newly detected pulmonary infiltration on a chest X-ray or computed tomography scan, accompanied by at least two of the following symptoms: a new or worsening cough, shortness of breath, increased sputum production, fever or hypothermia, pleuritic chest pain, hypoxia, confusion, or an abnormal WBC count (either leukopenia or leukocytosis). It is a major contributor to global mortality and morbidity, especially in elderly populations. This study aims to investigate the etiology of CAP in our region and analyze the clinical characteristics of patients diagnosed with CAP. This prospective, hospital-based study was conducted at Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, a 2,011-bed multispecialty hospital. The study included 100 patients over 18 years old, diagnosed with CAP, and hospitalized between January 2023 and January 2024. All patients underwent a thorough clinical assessment, and sputum cultures were collected on the day of admission. Patients under 18 years old, those who had been hospitalized within the preceding two weeks, individuals with pneumonia caused by tuberculosis oraspiration pneumonia, patients with compromised immune systems, and pregnant women were excluded. The study included 100 patients with a mean age of 53.13 years (±18.31). The most common age group was 59-68 years, which included 25 (25%) cases, followed by the 69-78 yearage group with 18 (18%) cases and the 18-28 yearage group with 15 (15%) cases. The majority were male, with 61 (61%) cases. Common symptoms included fever in 78 cases (78%), chest pain in 69 cases (69%), dyspnea in 65 cases (65%), and cough in 51 cases (51%). Sputum cultures showed growth in 65 cases (65%), with Klebsiella pneumoniae being the most prevalent pathogen in 28cases (43%), followed by Streptococcus pneumoniae in 18 cases (28%). Together, these two pathogens accounted for 46 out of 65 positive samples (70%). This study highlights the clinical profile and rising etiology of K. pneumoniae in CAPin adults in Western India, particularly in the elderly. These findings underscore the need for periodic updates on CAP etiology to inform empirical treatment strategies effectively. Future research should use advanced diagnostics and diverse samples to refine CAP management, with continuous monitoring to update treatment protocols.

Controversies in the management of community-acquired pneumonia in adults.

Community-acquired pneumonia (CAP) is a common infectious syndrome in Australia and a leading global cause of morbidity and mortality. It drives a significant amount of antimicrobial prescribing in Australia. Accurate assessment and stratification of CAP severity is important. However, adequate evaluation is challenging and controversy remains about the optimal method. Streptococcus pneumoniae is the most commonly identified bacterial pathogen causing CAP. As such, oral amoxicillin monotherapy is the mainstay of empirical therapy for low-severity CAP. The need to start empirical therapy for pathogens such as Mycoplasma pneumoniae and Legionella species in low-severity CAP remains controversial; evaluating the causative pathogen on clinical grounds alone is difficult. Oral antibiotics recommended for CAP (e.g. amoxicillin, doxycycline) have excellent bioavailability and may be used instead of intravenous therapy in some hospitalised patients. A duration of 5 days of antibiotic therapy is recommended in clinical practice guidelines for patients with uncomplicated CAP who meet stability criteria at follow-up.

Роль отдельных эссенциальных и токсичных микроэлементов в патогенезе внебольничной пневмонии.

Pneumonia remains one of the most pressing problems of pulmonology. Despite significant advances in antibacterial and antiviral therapy, mortality from this disease is not going down. Environmental factors play a significant role in the development of community-acquired pneumonia in adults. In the northern regions, such as the Republic of Karelia, environmental conditions unfavorable for human health act as risk factors that contribute to the occurrence or worsening of the disease. The Republic of Karelia, like other northern territories, has certain characteristics in terms of the content and distribution of chemical elements (or their compounds) in natural environments, making it a specific biogeochemical province. This survey discusses the role of individual essential and toxic trace elements in the pathogenesis of community-acquired pneumonia, which can help clarify and specify the causes of the long and complicated disease course. This opens up new prospects in the development of effective approaches to its treatment and prevention.

Effectiveness of S100 calcium-binding protein A12 combined with modified early warning score in the clinical diagnosis of adult community-acquired pneumonia.

Recent studies have found that S100 serum calcium-binding protein A12 (S100A12) has important significance in the expression of acute infectious diseases, and has high clinical application value in the differential diagnosis, prognosis and other aspects of acute infectious diseases. The accuracy of modified early warning score (MEWS) in evaluating the disease risk level of critically ill patients is comparable to Acute Physiology and Chronic Health Evaluation (APACHE II). Based on MEWS, 108 adult community-acquired pneumonia (CAP) patients were divided into the low-risk, intermediate-risk, and high-risk groups. The differences in invasive mechanical ventilation rate and mortality rate among each group were compared, and the differences of S100A12 in different levels of MEWS scores were compared through one-way analysis of variance. According to the prognosis after 30 days, the patients were divided into the death group and the survival group. Univariate and multivariate logistic regression analyses were used to study the influencing and independent factors of 30-day death in CAP patients. The sensitivity and specificity of S100A12, procalcitonin (PCT), and MEWS scores in predicting the 30-day death in CAP patients were evaluated using the receiver operating characteristic (ROC) curve, as well as the area under each indicator curve. The serum S100A12 concentration increased with the increase in the MEWS stratification, and the mechanical ventilation and mortality rates also increased significantly. Univariate and multivariate analyses were used to explore the factors influencing mortality in adult CAP patients after 30 days. The receiver-operating characteristics curve was used to analyze the sensitivity, specificity, and area under the curves of serum S100A12, PCT, and MEWS in predicting mortality in CAP patients after 30 days. The serum S100A12, PCT, and MEWS can effectively predict the mortality risk in adult CAP patients after 30 days. Serum S100A12 combined with MEWS has a high clinical application value in evaluating the severity and prognosis of adult CAP.

Study protocol: infectious diseases consortium (I3D) for study on integrated and innovative approaches for management of respiratory infections: respiratory infections research and outcome study (RESPIRO)

BackgroundCommunity-acquired respiratory infections are a leading cause of illness and death globally. The aetiologies of community-acquired pneumonia remain poorly defined. The RESPIRO study is an ongoing prospective observational cohort study aimed at developing pragmatic logistical and analytic platforms to accurately identify the causes of moderate-to-severe community-acquired pneumonia in adults and understand the factors influencing disease caused by individual pathogens. The study is currently underway in Singapore and has plans for expansion into the broader region.MethodsRESPIRO is being conducted at three major tertiary hospitals in Singapore. Adults hospitalised with acute community-acquired pneumonia or lower respiratory tract infections, based on established clinical, laboratory and radiological criteria, will be recruited. Over the course of the illness, clinical data and biological samples will be collected longitudinally and stored in a biorepository for future analysis.DiscussionThe RESPIRO study is designed to be hypothesis generating, complementary to and easily integrated with other research projects and clinical trials. The detailed clinical database and biorepository will yield insights into the epidemiology and outcomes of community-acquired lower respiratory tract infections in Singapore and the surrounding region and offers the opportunity to deeply characterise the microbiology and immunopathology of community-acquired pneumonia.

Рабдомиолиз — редкое внелегочное проявление внебольничной пневмонии, вызванной Mycoplasma pneumonia

Aim. To present a clinical case of a 19-year-old patient with community-acquired pneumonia (CAP) caused by Mycoplasma pneumoniae, which was complicated by a rare extrapulmonary manifestation in the form of rhabdomyolysis. Key points. The clinical case demonstrates a variant of mycoplasma CAP in an adult patient. M. pneumoniae infection was confirmed by a positive PCR test. Characteristic is contact with a patient with mycoplasma CAP in an infectious focus, a flu-like onset of the disease. Unlike most mild mycoplasma infections with a minimally expressed clinical picture and inflammatory response, the patient had a long period of febrile temperature and severe intoxication, significant laboratory changes and bilateral polysegmental lung damage. The development of signs of rhabdomyolysis (myalgia, increased creatine phosphokinase (CPK) to 2066 U/L, myoglobinuria) in the acute period of the disease is a rare extrapulmonary manifestation of mycoplasma CAP in adults, dangerous for the development of acute renal failure (ARF). Conclusion. The patient's young age, timely initiation of hydration, and antibacterial therapy aimed at M. pneumoniae made it possible to prevent the development of acute renal failure due to rhabdomyolysis. An increase in CPK, in the absence of other explanations for this phenomenon, should include mycoplasma CAP in the differential diagnosis of rhabdomyolysis. Keywords: community-acquired pneumonia, Mycoplasma pneumoniae, creatine phosphokinase, rhabdomyolysis.

Etiology of community-acquired pneumonia in adults in Russian hospitals after the COVID-19 pandemic: results of a multicenter prospective study

Objective. To study the etiology of community-acquired pneumonia (CAP) in adult hospitalized patients after the COVID-19 pandemic. Materials and Methods. The prospective multicenter study included patients 18 years and older with confirmed diagnosis of CAP admitted to 6 hospitals in different regions of Russia from July to November 2023. Etiology was confirmed by respiratory samples (sputum, tracheal aspirate) culture, blood culture (severe cases), and urinary antigen tests (Legionella pneumophila serogroup 1, Streptococcus pneumoniae). Mycoplasma pneumoniae, Chlamydia pneumoniae, and common respiratory viruses were identified using the real-time polymerase chain reaction (PCR) in respiratory samples. Qualitative PCR for S. pneumoniae and Haemophilus influenzae DNA tests were also applied. Results. Altogether 152 patients were enrolled, and significant CAP pathogens were identified in 96 (63%) cases; the median age of patients with verified etiology of CAP was 45 [34.8; 66] years, comorbidity index was 0.5 (0; 3.0) points. The most frequently detected pathogens were M. pneumoniae – 42 (44%), rhinovirus – 23 (24%), S. pneumoniae – 17 (18%) and SARS-CoV-2 – 13 (14%). Coinfection was registered in 22% of cases, the most common associations were M. pneumoniae + rhinovirus – 5 (3.3%), S. pneumoniae + rhinovirus – 3 (2%). Pneumococcal bacteremia was detected in 1 patient. In most patients CAP was non-severe; 17 (18%) patients required admission to the ICU. Hospital mortality was 7%. Conclusions. M. pneumoniae, respiratory viruses (mainly rhinovirus and SARS-CoV-2), and S. pneumoniae were the predominant CAP pathogens in hospitalized adults with CAP in the first months after the COVID-19 pandemiс. The use of an integrated approach to etiological diagnosis can significantly increase the proportion of patients with an established etiology of CAP.

Community-acquired pneumonia in adults hospitalized in the medical service.

Community-acquired pneumonia in adults hospitalized in the medical service.

Pneumococcal serotypes and risk factors in adult community acquired pneumonia 2018–20: a multicentre UK cohort study

BackgroundHigher-valency pneumococcal vaccines are anticipated. We aimed to describe serotype distribution and risk factors for vaccine-serotype community-acquired pneumonia (CAP) in the two years pre-SARS-CoV-2 pandemic. MethodsWe conducted a prospective cohort study of adults hospitalised with CAP at three UK sites between 2018 and 2020. Pneumococcal serotypes were identified using a 24-valent urinary-antigen assay and blood cultures. Risk factors associated with vaccine-type pneumonia caused by serotypes in the 13-, 15- and 20-valent pneumococcal conjugate vaccines (PCV13, PCV15, PCV20) and 23-valent pneumococcal polysaccharide vaccine (PPV23) were determined from multivariable analysis. FindingsOf 1921 adults hospitalised with CAP, 781 (40·7%, 95% confidence intervals (CI) 38·5-42·9%) had pneumococcal pneumonia. A single PCV13-serotype was detected in 242 (31·0%, 95% CI 27·8-34·3%) pneumococcal CAP patients, mostly serotype 3 (171/242, 70·7%, 95% CI 64·5-76·0%). The additional two PCV15-serotypes were detected in 31 patients (4%, 95% CI 2·8-5·6%), and PCV20-non13-serotypes in 192 (24·6%), with serotype 8 most prevalent (123/192, 64·1%, 95% CI 57·1-70·5%). Compared to PCV13-serotype CAP, people with PCV20-non13 CAP were younger (median age 62 versus 72 years, p<0·001) and less likely to be male (44% versus 61%, p=0·01). PPV23-non13-serotypes were found in 252 (32·3%, 95% CI 29·1-35·6%) pneumococcal CAP patients. InterpretationDespite mature infant pneumococcal programmes, the burden of PCV13-serotype pneumonia remains high in older adults, mainly due to serotype 3. PCV20-non13-serotype pneumonia is more likely in younger people with fewer pneumococcal risk factors. FundingUnrestricted investigator-initiated research grant from Pfizer; support from National Institute for Health Research (NIHR) Biomedical Research Centre, Nottingham.

Etiology of community-acquired pneumonia in children and adults based on 2015–2022 bacteriological and molecular genetic studies

The data on etiology of community-acquired pneumonia (CAP) remain contradictory, which is often assessed only according to bacteriological studies coming to a conclusion about the low frequency of major main pathogenStreptococcus pneumoniaеisolation. At the same time, there are very few observations of parallel examination of patients with CAP simultaneously by bacteriological and molecular genetic methods. There are no observations on the etiology of CAP in the long-term dynamics. The aim of the work is to analyze the etiology of CAP in children and adults based on 2015–2022 bacteriological and molecular genetic studies. The etiology of pneumonia was assessed using the data on posterior pharyngeal wall washes from 418 children and 483 adults hospitalized with a primary diagnosis of CAP at two large Perm medical organizations in 2015–2022. The samples were examined by the bacteriological method and polymerase chain reaction using commercial test systems with the amplifier “CFX96” (Bio-Rad, USA). The results showed thatS. pneumoniaе, despite implementing decreed vaccinations against pneumococcal infection, it remains the leading causative agent of CAP in both children and adults. The 2015–2022 frequency of pneumococcal discharge according to bacteriological studies was 9.7 per 100 examined, according to molecular genetic studies — 48.5 per 100 examined among children and adults in the study area. According to 2021–2022 vs 2015–2017 bacteriological studies, the frequency ofStaphylococcus aureusexcretion among children increased significantly, andS. pneumoniaеincreased among adults. According to the results of molecular genetic studies among children and adults, no significant changes in the etiology of CAP were found. In 2021–2022, SARS-CoV-2-positive vs SARS-CoV-2-negative patients with CAP infected had higher rate of isolatedS. aureus,KlebsiellapneumoniaеandHemophilus influenzae, i.e., those pathogens whose number increased in the long-term follow-up observations.

Pneumococcal Serotypes Associated with Community-Acquired Pneumonia Hospitalizations in Adults in Spain, 2016-2020: The CAPA Study.

Newer higher valency pneumococcal conjugate vaccines (PCVs) have the potential to reduce the adult community-acquired pneumonia (CAP) burden. We describe the evolution and distribution of adult community-acquired pneumonia (CAP) serotypes in Spain, focusing on serotypes contained in the 20-valent PCV (PCV20). This was a prospective, observational study of chest X-ray (CXR)-confirmed CAP in immunocompetent adults hospitalized in one of four Spanish hospitals between November 2016 and November 2020. Pneumococci were isolated from cultures and detected in urine using BinaxNow® and Pfizer serotype-specific urinary antigen tests UAD1 and UAD2. We included 1948 adults hospitalized with CXR-CAP. The median age was 69.0 years (IQR: 24 years). At least one comorbidity was present in 84.8% (n = 1653) of patients. At admission, 76.1% of patients had complicated pneumonia. Pneumococcus was identified in 34.9% (n = 680) of study participants. The PCV20 vaccine-type CAP occurred in 23.9% (n = 465) of all patients, 68.4% (n = 465) of patients with pneumococcal CAP, and 82.2% (83/101) of patients who had pneumococcus identified by culture. Serotypes 8 (n = 153; 7.9% of all CAP) and 3 (n = 152; 7.8% of all CAP) were the most frequently identified. Pneumococcus is a common cause of hospitalized CAP among Spanish adults and serotypes contained in PCV20 caused the majority of pneumococcal CAP.

Predictors of hospital mortality and multidrug-resistant pathogens in hospitalized pneumonia patients residing in the community

Background and objectiveThe 2019 ATS/ADSA guidelines for adult community-acquired pneumonia (CAP) eliminated healthcare-associated pneumonia (HCAP) and considered it to be a form of CAP. This concept, however, was based on studies with relatively small sample sizes. MethodsWe investigated the risk factors of 30-day mortality, and methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa infections in patients with pneumonia coming from the community using the Diagnosis Procedure Combination database, a nationwide discharge database of acute care hospitals. Furthermore, we compared these factors between CAP and HCAP. ResultsA total of 272,337 patients aged ≥20 years with pneumonia were grouped into 145,082 CAP patients and 127,255 HCAP patients. The 30-day mortality rate (8.9 % vs.3.3 %), MRSA infection (2.4 % vs. 1.4 %), and Pseudomonas aeruginosa infection (1.6 % vs. 1.0 %) were significantly higher in HCAP than in CAP patients. Multivariable logistic regression analysis showed that 12 of 13 identified predictors of mortality (i.e., high age, male, underweight, non-ambulatory status, bedsore, dehydration, respiratory failure, consciousness disturbance, hypotension, admitted in critical care, comorbidity of heart failure, and chronic obstructive pulmonary disease) were identical in CAP and HCAP patients. Similarly, five of six distinct risk factors for MRSA infection, and three of three for Pseudomonas aeruginosa infection were identical between the patients. ConclusionThe risk factors for mortality and MRSA or Pseudomonas aeruginosa infection were almost identical in patients with CAP and HCAP. The assessment of individual risk factors for mortality and MRSA or Pseudomonas aeruginosa infection in CAP and abandoning categorization as HCAP can improve and simplify empiric therapy.

The distribution of myeloid-derived suppressor cells subsets and up-regulation of programmed death-1/PD-L1 axis in peripheral blood of adult CAP patients.

Myeloid-derived suppressor cells (MDSCs) have been reported to expand and have a potent ability in the expansion of regulatory T cells in malignant and infectious disease. The current study was performed to investigate the role of MDSCs and possible immune mechanisms in dampening immune responses of community acquired pneumonia (CAP). This was a single-center cross-sectional study. The distribution of MDSCs subsets, the PD-1/PD-L1(L2) level of MDSCs subsets and Tregs in the peripheral blood of adult CAP patients and healthy control were measured by flow cytometry analysis. Peripheral blood mononuclear cells (PBMCs) from 63 adult CAP patients contained an elevated frequency of both G-MDSC (4.92±0.30 vs 2.25±0.21,p<0.0001) and M-MDSC (19.40±1.30 vs 9.64±0.57,p<0.001) compared to healthy controls. Treg in the peripheral blood of CAP patients exhibited increased expression of PD-1 and CTLA-4, accompanied by no difference of their frequency. Moreover, up-regulated expression of PD-L1 on MDSC subsets in the peripheral blood of CAP patients was also revealed. Of note, the frequency of circulating MDSCs subset displayed a positive correlation with neutrophil count percentage in blood in CAP patients. In summary, the significant expansion of circulating MDSCs subsets and the up-regulated expression of PD-1/PD-L1 level in CAP patients may suggest the possible involvement of PD-1/PD-L1axis in MDSCs mediated immune regulation on Treg at least partially in CAP patients.